feat: D24 fact intervals (--as-of) and bin/stack assistant helpers. (#37)

Store valid_from/valid_to on leafs and filter search by calendar day without
overloading D16 source staleness; stack start/start-assistant wires brain + PicoClaw.

.dockerignore

@@ -3,6 +3,7 @@
 var
 .git
 .github
+lib-ladybug
 __pycache__
 *.pyc
 *.lbug

.github/workflows/ci.yml

@@ -37,31 +37,61 @@ jobs:
           bash -n bin/db/ssh-tunnel
           bash -n bin/docker-entrypoint
           bash -n bin/kb/search
+          bash -n bin/cgo/zig
+          sh -n bin/cgo/zcc
+          sh -n bin/cgo/zc++
 
       - name: Python unit tests (offline, vendored tools)
         run: |
           uv run python -m unittest discover -s bin/tools -t .
 
-      - name: Go tests (root module, no ladybug cgo)
+      - name: Go tests (root module; duckdb-go CGO via gcc, no ladybug)
         run: |
-          go vet ./...
+          CC=gcc CXX=g++ CGO_CFLAGS= CGO_LDFLAGS= go vet ./...
-          go test ./... -count=1
+          CC=gcc CXX=g++ CGO_CFLAGS= CGO_LDFLAGS= go test ./... -count=1
 
       - name: brain ranking tests (no cgo / no ladybug)
         run: go test ./internal/brain/rank -count=1
 
       - name: facts/audit self (lexicon consistency, no network)
-        run: |
+        run: ./bin/facts/audit self
-          ./bin/facts/audit self 2>/dev/null || echo "audit: not yet implemented; gate skipped"
 
-      - name: kb/eval recall gate
+      - name: CGO via Zig (compile brain/search + eval)
         run: |
-          ./bin/kb/eval 2>/dev/null || echo "eval: not yet implemented; gate skipped"
+          chmod +x bin/cgo/zig bin/cgo/zcc bin/cgo/zc++
+          bin/cgo/zig go build -tags system_ladybug -o /tmp/brain-search ./bin/brain/search.go
+          bin/cgo/zig go build -tags 'system_ladybug,brain_eval' -o /tmp/brain-eval ./bin/brain/eval.go
+
+      - uses: actions/cache@v4
+        with:
+          path: ~/.cache/huggingface
+          key: ${{ runner.os }}-hf-potion-multilingual-128M
+
+      - name: recall@5 SoT (Zig bin/brain/eval.go)
+        run: |
+          uv run python bin/kb/index --rebuild --json
+          KB_ROOT="$PWD" /tmp/brain-eval --json
+
+  ocr:
+    name: OCR (tesseract fixture)
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-go@v5
+        with:
+          go-version-file: go.mod
+      - name: Install tesseract + poppler
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y --no-install-recommends \
+            tesseract-ocr tesseract-ocr-eng tesseract-ocr-deu poppler-utils
+      - name: Go OCR tests (synthetic HELLO PNG)
+        run: go test ./internal/ocr -count=1
 
   release:
     name: Release (semver)
     if: github.event_name == 'push' && github.ref == 'refs/heads/main'
-    needs: test
+    needs: [test, ocr]
     runs-on: ubuntu-latest
     permissions:
       contents: write

.gitignore

@@ -11,3 +11,6 @@ __pycache__/
 .secrets/
 lib-ladybug/
 go.work.local
+models/
+# Purged from git history. Do not re-add.
+docs/crm-associations-proof.md

AGENTS.md

@@ -3,7 +3,8 @@
 Evidence-first brain over the ops/eSlider stack. Facts need proof or they are
 `(not confirmed)`.
 
-Read first: [PLAN](PLAN.md) → [docs](docs/).
+Read first: [PLAN](PLAN.md) → [docs](docs/) → [roadmap](docs/roadmap.md)
+(epic [#16](https://git.produktor.io/eSlider/2dph/issues/16)).
 
 ## Method (detective, no fork)
 
@@ -39,19 +40,23 @@ PLAN.md       decisions + execution + open questions
 docs/         published docs
 skills/       in-project agent skills (vendored, no external links)
 bin/          self-describing tools bin/{subject}/{method}.go (shebang)
-bin/brain/    search.go serve.go index.go get.go stats.go eval.go watch.go
+bin/brain/    search.go serve.go index.go add.go get.go stats.go eval.go watch.go
 bin/chats/    sync.go import.go facts.go apply.go; libs in internal/chats
-bin/mail/     sync.go import.go (index_mail → brain/index.go)
+bin/mail/     sync.go import.go ocr.go (index_mail → brain/index.go)
-bin/markdown/ import.go (mistune leafs)
+bin/markdown/ import.go (H2 leaf split; Python bin/md/import fallback)
 bin/postgres/ query.go (read-only YAML)
 bin/git/      import.go (go-git history; Python shim execs it)
 bin/web/      search.go (SearXNG; Python shim execs it)
-internal/     shared Go (brain/rank is cgo-free; chats parsers; gitlog; websearch)
+bin/reasoner/ bakeoff.go (D18 CPU OpenAI tool-call bake-off)
+internal/     shared Go (brain/rank is cgo-free; facts D16; cli flaggy D23; chats; gitlog; websearch; reasoner; duckstats)
+bin/qa/       stats.go (DuckDB quantiles / JSONL count; gcc CGO, not Zig)
 bin/watch/    corpus watcher (used by bin/brain/watch.go)
 bin/tools/    vendored python libs behind bin/* (kblib, yamlout, websearch)
-bin/docker-entrypoint  container entrypoint (brain index|search|serve|watch)
+bin/cgo/      zig zcc zc++ (CGO via zig cc, not gcc)
+bin/stack/    start start-assistant stop status (compose + PicoClaw agent)
+bin/docker-entrypoint  container entrypoint (api: serve|search|watch; index: python)
 compose.yaml  docker composition (root level, not docker/)
-Dockerfile    multi-stage: python deps + static Go binaries
+Dockerfile    api (Zig CGO, no Python) + index (Python write)
 var/          kb.lbug, var/mail/*, caches (gitignored)
 .venv/        ladybug + model2vec + mistune
 ```
@@ -62,43 +67,58 @@ var/          kb.lbug, var/mail/*, caches (gitignored)
 bin/mail/sync.go --source onlyoffice,gmail --workers 8 --out var/mail   # raw message.json + attachments
 bin/mail/sync.go --source gmail --query 'from:example.com' --out var/mail  # Gmail search (default in:inbox)
 bin/mail/import.go --from-raw var/mail                                  # message.json → message.md (convert only)
-bin/brain/index.go --rebuild                                            # rebuild brain incl. all mail (fresh DB)
+bin/brain/index.go --rebuild --with-facts --with-chats
 ```
 
 - `sync` (Go) downloads messages + attachments; Gmail uses paginated list +
   `body.attachmentId` (not partId) for attachments.
 - `import` converts body + attachments to markdown. PDFs use poppler
-  `pdftotext -layout` fast path (~15ms); textless/scanned PDFs fall back to
+  `pdftotext -layout` fast path (~15ms); textless/scanned PDFs use
-  docling (isolated subprocess — its native onnx can segfault the parent).
+  `pdftoppm` + tesseract `eng+deu` (`bin/mail/ocr.go`). Optional
-  Conversion never touches the brain DB (crash safety).
+  `OCR_ENGINE=paddle`. Conversion never touches the brain DB (crash safety).
-- `index_mail` is a deprecation shim for `bin/brain/index.go --rebuild`. Ladybug
+- `index_mail` is a deprecation shim for `bin/brain/index.go --rebuild`. Bulk
-  corrupts its WAL when brand-new leafs are bulk-inserted while FTS/vector
+  rebuild still deletes `var/kb.lbug` and creates FTS/HNSW last. Single-leaf
-  indexes exist; a fresh DB with indexes created last is the only safe path.
+  write is `bin/brain/add.go` (safe while indexes exist; do not DROP INDEX).
   Keep conversion + indexing separate so a conversion crash can't leave the
   DB mid-transaction.
 
 ## Tools
 
 ```bash
-bin/facts/audit.go ["self"|"facts"|"info"|"stale"]  # 2-source + staleness gate
+bin/facts/audit.go ["self"|"db"|"contradict"]     # 2-source + D16 adjudication
 bin/facts/crm.go [--dry-run]                       # proof person↔company/company↔project (ooCRM × corpus SoT)
 bin/kb/search "query" [--repo X]                  # deprecated wrapper → bin/brain/search.go
 bin/brain/search.go "query" [--root facts|info]   # deduction search → YAML
+bin/brain/search.go "query" --as-of 2025-01-01    # D24 fact intervals
 bin/brain/search.go "query" --no-web              # local graph only
+source <(./bin/cli/complete.go bash)              # flaggy completions (D23)
+eval "$(bin/cgo/zig env)"                         # Zig cc + liblbug (not gcc)
+bin/brain/index.go --rebuild [--with-mail] [--with-facts] [--with-chats]
+bin/brain/add.go --text T --root facts --source "a.md x b.md"  # incremental write
+bin/brain/add.go --json                                      # stdin leaf or {leafs:[...]}
 bin/brain/get.go <id> [--body] [--json]          # Go read; Python bin/kb/get CI fallback
 bin/brain/stats.go [--json]
 bin/brain/eval.go [--json]                       # recall@5; questions in internal/brain/rank
 bin/brain/serve.go                               # HTTP :8630; GET /openapi.json POST /mcp
-bin/markdown/import.go [dir]                      # mistune leaves → YAML
+bin/stack/start                                  # brain HTTP/MCP (reuse healthy :8630)
+bin/stack/start-assistant                        # + reasoner + PicoClaw agent
+bin/stack/status                                 # YAML health
+bin/stack/stop                                   # compose stop; volumes kept
+bin/markdown/import.go [dir]                      # H2 leafs → YAML; Python bin/md/import fallback
 bin/git/import.go [REPO] [--json] [--limit N]     # go-git history → commit leafs
 bin/web/search.go "query" [--json]                # SearXNG; throttled ≠ absence
+bin/reasoner/bakeoff.go [--model ID] [--json]     # D18 CPU tool-call bake-off
 bin/postgres/query.go --profile onlyoffice -c 'SELECT 1'
+bin/qa/stats.go                                  # D22 DuckDB quantiles / JSONL (gcc CGO)
+bin/mail/ocr.go <image|pdf>                      # tesseract eng+deu (scans)
 bin/md/tables                                     # what the graph holds → YAML
 bin/brain/deduce "question"                       # thinking wrapper
 ```
 
 Never start a shell command with `cd` — use the tool working-directory
-parameter. Search before reading whole files.
+parameter. Search before reading whole files. For YAML/JSON/XML/CSV/TOML/HCL
+prefer mikefarah/yq (`skills/yq/SKILL.md`). For bulk rows and quantiles use
+duckdb-go (`internal/duckstats`, `skills/duckdb/SKILL.md`), not Ladybug.
 
 ## GitHub safety rules (ABSOLUTE — never violate)
 

Dockerfile

@@ -1,5 +1,13 @@
 # syntax=docker/dockerfile:1
-FROM python:3.12-slim AS base
+#
+#   docker build --target api -t 2dph:api .
+#   docker build --target index -t 2dph:index .
+#
+# API: Go + ladybug via Zig CGO (no CPython).
+# Index: Python write path (profile `index` until brain/add is v2).
+
+# --- Python sidecar (Ladybug write / rebuild) ---
+FROM python:3.12-slim AS index
 
 ENV PYTHONUNBUFFERED=1 \
     PYTHONDONTWRITEBYTECODE=1 \
@@ -8,26 +16,16 @@ ENV PYTHONUNBUFFERED=1 \
 
 WORKDIR /app
 RUN id -u 2dph 2>/dev/null || useradd --create-home --uid 1001 2dph
+RUN apt-get update \
+    && apt-get install -y --no-install-recommends \
+         poppler-utils tesseract-ocr tesseract-ocr-eng tesseract-ocr-deu \
+    && rm -rf /var/lib/apt/lists/*
 
-# deps layer-first: rebuild only on dependency change
 COPY requirements.lock.txt /tmp/requirements.lock.txt
 RUN python -m pip install --no-cache-dir -r /tmp/requirements.lock.txt \
     && rm /tmp/requirements.lock.txt
 
-# Go services: static binaries, no interpreter at runtime
-FROM golang:1.25 AS go-build
-WORKDIR /src
-COPY go.mod ./
-COPY bin/server ./bin/server
-COPY bin/watch ./bin/watch
-RUN CGO_ENABLED=0 go build -o /serve ./bin/server \
-    && CGO_ENABLED=0 go build -o /watch ./bin/watch
-
-# runtime: python toolchain + Go services
-FROM base
 COPY . .
-COPY --from=go-build /serve /app/bin/serve
-COPY --from=go-build /watch /app/bin/watch
 RUN chmod +x /app/bin/docker-entrypoint \
     && chown -R 2dph:2dph /app
 USER 2dph
@@ -37,5 +35,51 @@ ENV PATH="/app/bin:${PATH}" \
     KB_ROOT=/app
 HEALTHCHECK --interval=30s --timeout=5s --start-period=10s --retries=3 \
     CMD python -c "import model2vec, ladybug, mistune; print('ok')" || exit 1
-
 ENTRYPOINT ["/app/bin/docker-entrypoint"]
+
+# --- Go API: CGO with Zig, not gcc ---
+FROM golang:1.26-bookworm AS api-build
+WORKDIR /src
+RUN apt-get update \
+    && apt-get install -y --no-install-recommends curl xz-utils ca-certificates \
+    && rm -rf /var/lib/apt/lists/*
+
+COPY bin/cgo ./bin/cgo
+RUN chmod +x bin/cgo/zig bin/cgo/zcc bin/cgo/zc++ \
+    && ./bin/cgo/zig env >/dev/null
+
+COPY go.mod go.sum ./
+RUN go mod download
+
+COPY . .
+ENV CGO_RPATH=/usr/local/lib
+RUN eval "$(./bin/cgo/zig env)" \
+    && go build -tags brain_serve,system_ladybug -o /out/brain-serve ./bin/brain/serve.go \
+    && go build -tags system_ladybug -o /out/brain-search ./bin/brain/search.go \
+    && CGO_ENABLED=0 go build -tags brain_watch -o /out/brain-watch ./bin/brain/watch.go
+
+FROM debian:bookworm-slim AS api
+RUN apt-get update \
+    && apt-get install -y --no-install-recommends libssl3 ca-certificates wget \
+    && rm -rf /var/lib/apt/lists/* \
+    && useradd --create-home --uid 1001 2dph
+COPY --from=api-build /out/brain-serve /usr/local/bin/brain-serve
+COPY --from=api-build /out/brain-search /usr/local/bin/brain-search
+COPY --from=api-build /out/brain-watch /usr/local/bin/brain-watch
+COPY --from=api-build /src/lib-ladybug/liblbug.so.0.19.1 /usr/local/lib/liblbug.so.0.19.1
+COPY bin/docker-entrypoint /usr/local/bin/docker-entrypoint
+RUN chmod +x /usr/local/bin/docker-entrypoint \
+    && ln -s liblbug.so.0.19.1 /usr/local/lib/liblbug.so.0 \
+    && ln -s liblbug.so.0 /usr/local/lib/liblbug.so \
+    && ldconfig
+USER 2dph
+ENV KB_ROOT=/data \
+    KB_PORT=8630 \
+    LD_LIBRARY_PATH=/usr/local/lib \
+    HF_HOME=/data/hf
+WORKDIR /data
+EXPOSE 8630
+HEALTHCHECK --interval=30s --timeout=5s --start-period=10s --retries=3 \
+    CMD wget -qO- http://127.0.0.1:8630/health || exit 1
+ENTRYPOINT ["/usr/local/bin/docker-entrypoint"]
+CMD ["serve"]

PLAN.md

@@ -4,7 +4,14 @@ A brain that loves facts and deduction. Evidence-first knowledge graph + hybrid
 RAG over the operational Brain/ops/eSlider stack. Built like Sherlock
 Holmes: nothing is asserted unless it has proof.
 
-Status: **in progress** — this file is the plan and the record of decisions.
+Status: **v1 in** (epic [#16](https://git.produktor.io/eSlider/2dph/issues/16) closed).
+v2 board: milestone [v2](https://git.produktor.io/eSlider/2dph/milestone/13) —
+OCR [#6](https://git.produktor.io/eSlider/2dph/issues/6) in,
+[#29](https://git.produktor.io/eSlider/2dph/issues/29) OQ1 in,
+[#30](https://git.produktor.io/eSlider/2dph/issues/30) OQ3 in,
+[#34](https://git.produktor.io/eSlider/2dph/issues/34) D23 in,
+[#36](https://git.produktor.io/eSlider/2dph/issues/36) OQ5/D24 in.
+Gap: [docs/roadmap.md](docs/roadmap.md).
 
 ## What
 
@@ -29,9 +36,9 @@ detective method: **a fact needs ≥2 independent sources or it is
 | D3 | web search | Go client `bin/web/search.go` (`internal/websearch`). SearXNG URL is config (`BRAIN_SEARCH_URL`). Optional Compose profile `searxng` (sanitized settings). Do not run a second copy on a host that already has one. Empty/`throttled` ≠ “nothing exists”. |
 | D4 | embeddings | **model2vec** `minishlab/potion-multilingual-128M` instead of embeddinggemma. |
 | D5 | parser | **mistune** for MD → leaf extraction (duckdb-md documented as future optional SQL/export layer, not v1). |
-| D6 | graph engine | **LadybugDB**. Go is the service (`bin/brain/search.go`, `bin/brain/serve.go` in-process, `internal/brain`). Read path (`get.go` / `stats.go` / `eval.go`) is Go + cgo. Python `bin/kb/{get,stats,eval}` is the CI fallback (GitHub runners have no ladybug cgo). Index/write stays Python until the Go write path is safe. |
+| D6 | graph engine | **LadybugDB**. Go is the service (`bin/brain/search.go`, `bin/brain/serve.go` in-process, `internal/brain`). Read path is Go + Zig CGO (D21). Python `bin/kb/{get,stats,eval}` is the CI fallback when Zig/libs are not fetched. Incremental write is Python `bin/kb/add` (`bin/brain/add.go`). Bulk rebuild stays `compose --profile index` until the Go write path is safe. |
 | D7 | db access | `db-yaml`/`psql-yq`-style, read-only, YAML out. OnlyOffice Postgres via SSH tunnel (`127.0.0.1:5433`). |
-| D8 | evidence | detective method: ≥2 independent sources or `(not confirmed)`. Auto-pair docker ps × compose × ssh-config × docs. |
+| D8 | evidence | detective method: ≥2 independent sources or `(not confirmed)`. 2-source auto-pair docker ps × compose × ssh-config × docs. |
 | D9 | facts/goal model | Who / What / How / Where / When + evidence + confidence on every edge. |
 | D10 | versioning | everything is a leaf with `sha256 + observed_at + source_rev`; `File-[:HAS_VERSION]->Commit-[:AUTHORED]->Person`. Stale = `source_rev` < git HEAD. |
 | D11 | strong/weak | `root` column: `facts` (strong) vs `info` (weak). Answer is `confirmed` only from facts root. |
@@ -39,11 +46,15 @@ detective method: **a fact needs ≥2 independent sources or it is
 | D13 | portfolio | start graph `(Person:eslider)-[:HAS]->(Portfolio)`, associate other natural/juristic persons later. |
 | D14 | tooling style | `bin/{subject}/{method}.go` shebang (e.g. `bin/brain/search.go`). Shared code in `internal/`. One root `go.mod` + `go.work`. No `bin/*/main.go`, no nested modules. |
 | D15 | repo | Gitea [`eSlider/2dph`](https://git.produktor.io/eSlider/2dph) is origin + [issues](https://git.produktor.io/eSlider/2dph/issues). GitHub `eSlider/2dph` is the public clone (PRs + Actions CI). No direct `main` pushes. TDD → PR → CI green → merge. |
-| D16 | contradictions | ≥2 yes vs ≥2 no → unrelated sources conflict → hypothesis → `(not confirmed)`. Resolution (authority, staleness adjudication) = **v2**, tracked as open question. |
+| D16 | contradictions | ≥2 yes vs ≥2 no → hypothesis → `(not confirmed)` until a rule fires. Order: **temporal_freshness** (fresh ≥2 vs stale minority), then **authority_pairing** (runtime/config A×B beats narrative C). Store as `a x b vs c x d` on hypothesis leafs. `bin/facts/audit contradict`. [#29](https://git.produktor.io/eSlider/2dph/issues/29). |
 | D17 | assertion gate | Fact-check every *claim* (facts → info → live → web), not every edit. `bin/brain/search.go` adds a `web` block when there is no facts hit (`throttled`/`skipped`/`refused` ≠ absence). `--root` and `--no-web` stay local. Missing graph ≠ “does not exist”. |
-| D18 | reasoner | Pluggable OpenAI-compatible URL. RAM: Qwen3.5-9B. Quality: Bonsai-27B or Qwen3.6-27B. No official Qwen3.6-9B. |
+| D18 | reasoner | Pluggable OpenAI-compatible URL (`REASONER_BASE_URL`). RAM: `Qwen/Qwen3.5-9B`. Quality: `prism-ml/Bonsai-27B-gguf` or `Qwen/Qwen3.6-27B`. No official Qwen3.6-9B. CPU bake-off: `bin/reasoner/bakeoff.go` + compose profile `reasoner` (`OLLAMA_NUM_GPU=0`, `:11435`). PicoClaw is compose profile `picoclaw`; tools are `search`/`get`/`audit`. Weights are not copied into the 2dph image. Agent lever/loop: [#15](https://git.produktor.io/eSlider/2dph/issues/15). |
 | D19 | git history | [go-git](https://github.com/go-git/go-git) via `bin/git/import.go`. No subprocess of the git binary. Conversion prints commit leafs; brain write is `bin/brain/index.go`. |
-| D20 | agent API | OpenAPI + MCP are generated from the same `internal/httpapi.Ops` table as `bin/brain/serve.go` handlers. `GET /openapi.json`, `POST /mcp` (JSON-RPC tools/list + tools/call). Tool names match OpenAPI paths (`search`/`get`/`stats`/`audit`). |
+| D20 | agent API | OpenAPI + MCP are generated from the same `internal/httpapi.Ops` table as `bin/brain/serve.go` handlers. `GET /openapi.json`, `POST /mcp` (JSON-RPC tools/list + tools/call). Tool names match OpenAPI paths (`search`/`get`/`stats`/`audit`/`ingest`). |
+| D21 | CGO | Ladybug/tokenizers CGO is compiled with **Zig** (`bin/cgo/zcc` → `zig cc -target …-linux-gnu`), not gcc. `bin/cgo/zig` pins Zig 0.14.1 + liblbug 0.19.1 + libtokenizers 1.27.0. Compose `target: api` has no CPython; write/rebuild is profile `index`. |
+| D22 | analytics | **duckdb-go** in-process (`internal/duckstats`, `bin/qa/stats.go`) for quantiles/JSONL. Links with **gcc/g++**, not Zig. Ladybug stays the graph; web-search cache stays modernc sqlite. Slice small structured docs with **mikefarah/yq**, not kislyuk/jq. [#30](https://git.produktor.io/eSlider/2dph/issues/30). |
+| D23 | CLI | **flaggy** (`github.com/integrii/flaggy`, 0 deps). Flags at any position. Wrapper `internal/cli`. Bash complete: `source <(./bin/cli/complete.go bash)`. No cobra, no stdlib `flag` in Go tools. Search does not intercept the word `completion`. [#34](https://git.produktor.io/eSlider/2dph/issues/34). |
+| D24 | fact intervals | Leaf `valid_from` / `valid_to` (YYYY-MM-DD, inclusive; empty = open/legacy). Search `--as-of` / MCP `as_of` keeps facts active that day. Not D16 `temporal_freshness` (source stale vs HEAD). Empty interval = always visible. [#36](https://git.produktor.io/eSlider/2dph/issues/36). |
 
 ## Architecture
 
@@ -54,21 +65,28 @@ detective method: **a fact needs ≥2 independent sources or it is
   skills/                   in-project skills (web-search, postgres, brain, picoclaw, diataxis-docs)
   bin/
     facts/extract.go audit.go crm.go  # D14 shebang; Python implementation
-    kb/index                Python write path (called by bin/brain/index.go)
+    kb/index                Python bulk write (called by bin/brain/index.go)
+    kb/add                  Python incremental write (called by bin/brain/add.go)
     brain/index.go          rebuild FTS + HNSW (incl. --with-mail)
+    brain/add.go            incremental leaf write (no rebuild)
     brain/get.go stats.go eval.go  # Go read (cgo); Python bin/kb/* CI fallback
     brain/watch.go
-    brain/search.go         deduction: facts → info → web-search
+    brain/search.go         deduction: facts → info → web
-    brain/serve.go          HTTP API in-process + OpenAPI/MCP (D20); compose profile picoclaw
+    cli/complete.go         flaggy bash/zsh/fish complete (D23)
+    brain/serve.go          HTTP API in-process + OpenAPI/MCP (D20); Zig CGO (D21)
+    cgo/zig zcc zc++        CGO toolchain (zig cc, not gcc)
     mail/import.go          JSON → markdown (no brain write)
-    markdown/import.go      mistune leaves
+    markdown/import.go      H2 leaf split (Go); Python bin/md/import fallback
     postgres/query.go       read-only YAML (wraps bin/db/psql-yq)
     git/import.go           go-git history (no git binary; conversion only)
     web/search.go           SearXNG client (throttled ≠ absence)
+    reasoner/bakeoff.go     CPU tool-call bake-off (D18; OpenAI tools)
     chats/sync.go import.go facts.go apply.go
                             (libs in internal/chats; no chats index)
+    mail/ocr.go             tesseract eng+deu (pdftoppm scans)
     md/import               (deprecated; bin/markdown/import.go)
     brain/extract  brain/audit       brain/deduce    (thinking wrapper)
+    stack/start start-assistant stop status
     web/search               (deprecated shim → web/search.go)
     db/psql-yq               (vendored)
     ssh-tunnel               onlyoffice pg tunnel 5433
@@ -80,10 +98,14 @@ detective method: **a fact needs ≥2 independent sources or it is
 
 Node tables: `Person, Service, Host, Container, Repo, File, Commit, Leaf`.
 `Leaf(embedding FLOAT[N])` — FTS on `text`, HNSW vector index on `embedding`.
-Edges: `RUNS / USES / HAS_VERSION / AUTHORED / ABOUT / ASSOCIATED / SIMILAR_0.85`.
+Edges: `RUNS / USES / FROM_FILE / HAS_VERSION / AUTHORED / ABOUT / ASSOCIATED / SIMILAR_0.85`.
+`FROM_FILE` / `HAS_VERSION` / `AUTHORED`: `bin/brain/search.go --hop N` walks
+them from each hit (1=File, 2=Commit, 3=Person). Rebuild writes
+`Leaf-[:FROM_FILE]->File`; git import writes the rest.
 
 Common props on every node/edge: `root`, `confidence`, `evidence[]`, `how`,
-`where`, `when`, `source_rev`.
+`where`, `when`, `source_rev`. Leaf interval of truth (D24): `valid_from`,
+`valid_to`.
 
 ## Config
 
@@ -98,26 +120,32 @@ Common props on every node/edge: `root`, `confidence`, `evidence[]`, `how`,
 
 - `bin/{subject}/{method}` — line 2 is a usage comment (mirrors `psql-yq`).
 - bash + python primary; golang via Go shebang when a compiled helper is right.
-- YAML default output, `--json` for machines. Slice with `yq`.
+- YAML default output, `--json` for machines. Slice with mikefarah/yq.
 - Everything that touches the network / DB is read-only, throttled, cached.
 - Tests (TDD) gate every commit; `gh` + CI/CD on every push.
 
 ## Open questions (v2)
 
-- OQ1: mutually-contradicting evidence — how to resolve (authority weighting,
+- OQ1: **in** — D16 adjudication: `temporal_freshness` then `authority_pairing`.
-  temporal freshness, audit adjudication).
+  Unresolved 2v2 stays hypothesis. [#29](https://git.produktor.io/eSlider/2dph/issues/29).
-- OQ2: OCR pipeline for pdfs/images/docs — mostly solved: poppler pdftotext
+- OQ2: OCR — **in**. `pdftotext -layout` first; scans `pdftoppm` + tesseract
-  fast-path for born-digital PDFs, docling fallback for the ~5% textless ones.
+  `eng+deu` (`bin/mail/ocr.go`, `internal/ocr`). No gocv, no gosseract CGO
-- OQ3: optional duckdb-md layer for `SELECT … FORMAT MARKDOWN` export/write-back.
+  (D21 Zig owns Ladybug CGO). Optional `OCR_ENGINE=paddle` / compose profile
+  `ocr-paddle`. Docling left the default path. [#6](https://git.produktor.io/eSlider/2dph/issues/6).
+- OQ3: **in** — duckdb-go (`internal/duckstats`, `bin/qa/stats.go`) for
+  quantiles / JSONL count. Not a second graph. [#30](https://git.produktor.io/eSlider/2dph/issues/30).
 - OQ4: YAML-first storage for leafs — deferred: JSON is ~10x faster to
   serialize and unambiguous; YAML only where humans edit files.
+- OQ5: **in** — fact `valid_from` / `valid_to` + `--as-of` / MCP `as_of` (D24).
+  Not D16 `temporal_freshness`. [#36](https://git.produktor.io/eSlider/2dph/issues/36).
 
 ## Mail pipeline (done)
 
 1. `bin/mail/sync.go` (Go, 8 workers) — paginated Gmail/OnlyOffice download.
    Gmail attachments key off `body.attachmentId`, not MIME `partId`.
 2. `bin/mail/import.go --from-raw` — message.json → message.md; PDFs via
-   `pdftotext -layout` (~15ms) with docling subprocess fallback; ICS sidecars
+   `pdftotext -layout` (~15ms); textless/scanned PDFs `pdftoppm` + tesseract
+   `eng+deu`. ICS sidecars
    Latin-1→UTF-8 normalized.
 3. `bin/brain/index.go --rebuild` — fresh rebuild (repo corpus + mail) because ladybug
    corrupts its WAL on bulk-insert into an already-indexed DB. Conversion and
@@ -134,10 +162,9 @@ Common props on every node/edge: `root`, `confidence`, `evidence[]`, `how`,
 2. `go test ./internal/brain/rank` (cgo-free ranking + flag parser)
 3. python -m unittest discover -s bin/tools (includes published-docs SoT)
 4. `bin/facts/audit self` (lexicon internal consistency; `bin/facts/audit.go` is the D14 wrapper)
-5. `bin/kb/eval` (recall@5 ≥ 0.95). Local SoT is `bin/brain/eval.go`; CI uses
+5. `bin/brain/eval.go` via Zig (recall@5 ≥ 0.95). Python `bin/kb/eval` is an
-   the Python twin until the runner has ladybug cgo. Questions live in
+   explicit fallback, not the CI SoT.
-   `internal/brain/rank`.
+6. `bin/cgo/zig go build -tags system_ladybug` (compile search with zig cc; fetches pinned zig+libs).
-6. md-docs build/lint if docs tooling arrives.
 
 Feedback loop: every commit → PR → CI → green/gate → merge. Same discipline as
 `db/tech-poc`: contract first where there is an OpenAPI/message shape.
@@ -150,5 +177,22 @@ Feedback loop: every commit → PR → CI → green/gate → merge. Same discipl
 4. .venv: ladybug + model2vec + mistune
 5. schema + tools with TDD (kb + md + facts + brain)
 6. ~/.config/brain config
-7. corpus extraction (facts/info)
+7. corpus extraction (facts/info) — **in**: [#18](https://git.produktor.io/eSlider/2dph/issues/18)
 8. verify: web-search smoke, onlyoffice pg, md-db round-trip, eval, audit
+
+## Gap to v1 (epic #16)
+
+Remaining: none for epic #16 (v1). Board:
+[epic #16](https://git.produktor.io/eSlider/2dph/issues/16),
+milestone [v1 detective brain](https://git.produktor.io/eSlider/2dph/milestone/12).
+Narrative: [docs/roadmap.md](docs/roadmap.md).
+
+| Order | Issue | Gap |
+|-------|-------|-----|
+| 1 | [#14](https://git.produktor.io/eSlider/2dph/issues/14) | **in** — `bin/brain/add.go` / `POST /ingest` write facts+info without deleting `kb.lbug`. Bulk corpus still `--rebuild`. Leftover Python (mail/facts) is not the living-graph blocker. |
+| 2 | [#17](https://git.produktor.io/eSlider/2dph/issues/17) | **in** — `--hop N` walks `FROM_FILE` → `HAS_VERSION` → `AUTHORED` (max 3). |
+| 3 | [#18](https://git.produktor.io/eSlider/2dph/issues/18) | **in** — `--with-facts` / `--facts-json` land `root=facts`; `--with-chats` indexes `var/chats/md`. WhatsApp sync is out of v1. |
+| 4 | [#15](https://git.produktor.io/eSlider/2dph/issues/15) | **in** — lever/loop documented (`search` → `get` → `audit`). |
+| 5 | [#19](https://git.produktor.io/eSlider/2dph/issues/19) | **in** — CI recall SoT is `bin/brain/eval.go` via Zig. Python `bin/kb/eval` stays as an explicit fallback. |
+
+Does **not** block epic close: OQ4. OCR [#6](https://git.produktor.io/eSlider/2dph/issues/6), OQ1 [#29](https://git.produktor.io/eSlider/2dph/issues/29), OQ3 [#30](https://git.produktor.io/eSlider/2dph/issues/30) are **in**.

README.md

@@ -7,14 +7,16 @@
 [![Latest Release](https://img.shields.io/github/v/tag/eSlider/2dph?sort=semver&label=release)](https://github.com/eSlider/2dph/releases)
 [![GitHub Stars](https://img.shields.io/github/stars/eSlider/2dph?style=social)](https://github.com/eSlider/2dph/stargazers)
 
-An evidence-first brain over the operational eSlider stack. **Facts need two
+An evidence-first brain. **Facts need two independent sources, or they are
-independent sources, or they are `(not confirmed)`.**
+`(not confirmed)`.** Cursor is not the runtime.
 
-`2dph` is a single embedded knowledge graph (LadybugDB = Kuzu successor) with
+`2dph` is a single embedded knowledge graph (LadybugDB) with native **HNSW
-native **HNSW vector** + **BM25 full-text** indexes, built from markdown,
+vector** + **BM25 full-text** indexes. Search is *deduction*: confirmed facts
-compose files, ssh config, docker state, and git history. Search is
+first, supporting info second, `web-search` as the independent second source
-*deduction*: confirmed facts first, supporting info second, `web-search` as
+when the local graph cannot confirm.
-the independent second source when the local graph cannot confirm.
+
+Run it: [docs/runbook.md](docs/runbook.md). Design: [docs/design.md](docs/design.md).
+Docs index: [docs/README.md](docs/README.md).
 
 ## Architecture
 
@@ -31,7 +33,7 @@ graph TB
         EX["bin/facts/extract.go<br/>2-source pairing"]
         AU["bin/facts/audit.go<br/>confidence + staleness"]
         IDX["bin/brain/index.go<br/>chunk + embed"]
-        MD["bin/markdown/import.go<br/>mistune leaves"]
+        MD["bin/markdown/import.go<br/>H2 leaf split"]
         SR["bin/brain/search.go<br/>deduction"]
     end
 
@@ -74,7 +76,7 @@ graph TB
 ## The method
 
 Every assertion is `Who / What / How / Where / When + evidence + confidence`,
-mirroring the detective detective skill: **≥2 independent sources confirm a
+mirroring the detective method: **≥2 independent sources confirm a
 fact; conflicting sources or a single source → `hypothesis` → `(not confirmed)`.**
 
 | root | meaning | used for answers |
@@ -94,7 +96,7 @@ bin/brain/stats.go                                   # index health
 bin/brain/eval.go                                    # recall@5 gate
 ```
 
-`--hop` is not implemented (needs File/FROM_FILE edges); the flag errors instead of walking. `bin/kb/search` is a deprecated wrapper around `bin/brain/search.go`.
+`--hop N` walks File/Commit/Person from each hit (max 3). `bin/kb/search` is a deprecated wrapper around `bin/brain/search.go`.
 
 Git history is read with [go-git](https://github.com/go-git/go-git) (no git binary):
 
@@ -118,23 +120,24 @@ Mail is a first-class corpus (retrievable through the same search):
 ```bash
 bin/mail/sync.go --source onlyoffice,gmail --workers 8 --out var/mail  # raw sync (Go)
 bin/mail/import.go --from-raw var/mail                                  # JSON → markdown
+bin/brain/add.go --text T --root facts --source "a.md x b.md"
+bin/brain/index.go --rebuild --with-facts --with-chats                  # facts extract + chats md
 bin/brain/index.go --rebuild                                            # rebuild brain (incl. mail)
 bin/brain/search.go "invoice from last week"                            # same search over mail leafs
 ```
 
 ## Storage
 
-- **LadybugDB** — single `var/kb.lbug`, Cypher property graph, HNSW + BM25
+- **LadybugDB** — single `var/kb.lbug`, Cypher + HNSW + BM25, embedded.
-  in one engine, embedded (no server), ACID, read-only-safe for concurrent
+  Read tools (`get` / `stats` / `eval`) are Go + Zig CGO (`bin/cgo/zcc`).
-  readers. Read tools (`get` / `stats` / `eval`) are Go + cgo; Python
+  Python fallbacks stay for CI until the runner fetches Zig. Incremental
-  `bin/kb/{get,stats,eval}` is the CI fallback. **Never `DROP INDEX` FTS/VECTOR** on Ladybug 0.19: DROP leaves
+  write is `bin/brain/add.go` (Python `kblib.add_leafs`). Bulk rebuild is
-  ghost catalog tables (`_0_Leaf_vec_UPPER`) so recreate fails while
+  Compose profile `index` (`bin/brain/index.go --rebuild`).
-  `SHOW_INDEXES` omits HNSW. Fresh indexes = delete `var/kb.lbug` +
+- **model2vec** — `potion-multilingual-128M` (256-dim), CPU, no Ollama
-  `bin/brain/index.go --rebuild`. Use `ensure_indexes()` after upserts.
+  runtime dependency.
-- **model2vec** — `potion-multilingual-128M` static embeddings (256-dim),
+- facts and info split by `root` but written in the same transaction.
-  CPU-fast, deterministic, no Ollama runtime dependency.
+
-- facts and info split semantically by `root` column but written inside the
+Ladybug 0.19 DROP INDEX warning: [docs/runbook.md](docs/runbook.md).
-  same transaction.
 
 ## Tooling conventions
 
@@ -145,32 +148,43 @@ machines. Tests gate every commit. HTTP: `bin/brain/serve.go` calls
 
 ## Development
 
+See the portable runbook: [docs/runbook.md](docs/runbook.md).
+
 ```bash
-uv venv .venv                                  # Python 3.12, uv-managed
+uv venv .venv
-uv pip install -r requirements.lock.txt        # pinned toolchain
+uv pip install -r requirements.lock.txt
-bin/facts/audit.go self                        # lexicon consistency gate
+bin/facts/audit.go self
-go test ./... && python -m unittest discover -s bin/tools -t .
+go test ./... && uv run python -m unittest discover -s bin/tools -t .
 ```
 
 Docker (optional, cached model + var volumes):
 
 ```bash
-docker compose run --rm brain index            # (re)index corpus
+bin/stack/start                                # brain HTTP/MCP :8630
-docker compose run --rm brain search "query"   # one-shot query
+bin/stack/start-assistant                      # + qwen3.5:9b + PicoClaw agent
-docker compose run --rm brain serve            # bin/brain/serve.go
+bin/stack/status
+bin/stack/stop
+docker compose up -d brain                     # API (Zig CGO serve :8630)
+docker compose --profile index run --rm index  # Python Ladybug rebuild
 docker compose --profile picoclaw up brain-mcp # MCP on 127.0.0.1:8630
+docker compose --profile reasoner up -d reasoner  # CPU Ollama 127.0.0.1:11435
 docker compose up brain-watch                  # auto re-index on change
 ```
 
 ## Related
 
+eSlider DevOps engineer practice: ops, OnlyOffice, and mail feed the facts
+root through `bin/facts/extract` (two-source pairing).
+
 - [go-second-brain](https://github.com/eSlider/go-second-brain) — the earlier
   Neo4j + Qdrant + Matrix RAG brain
 - [agent-skills](https://github.com/eSlider/agent-skills) — upstream
   skills (`web-search`, `postgres`, …) that 2dph integrates
 - detective method — the two-source method
 
-Work board (issues): [git.produktor.io/eSlider/2dph/issues](https://git.produktor.io/eSlider/2dph/issues).
+Work board (issues): [epic #16](https://git.produktor.io/eSlider/2dph/issues/16)
+on [git.produktor.io/eSlider/2dph/issues](https://git.produktor.io/eSlider/2dph/issues).
 PRs and CI: GitHub [`eSlider/2dph`](https://github.com/eSlider/2dph).
 
-See [PLAN.md](PLAN.md) for decisions, execution status, and v2 open questions.
+See [PLAN.md](PLAN.md) for decisions, [docs/roadmap.md](docs/roadmap.md) for
+the gap to v1, and v2 open questions.

bin/brain/add.go

@@ -0,0 +1,21 @@
+//usr/bin/env go run -tags=brain_add "$0" "$@"; exit
+//go:build brain_add
+//
+// bin/brain/add.go - incremental leaf write (Python kblib, no rebuild).
+//
+//	./bin/brain/add.go --text T --root facts --source "a.md x b.md"
+//	./bin/brain/add.go --json
+//
+// D6: write stays Python. Does not delete var/kb.lbug.
+// NOTE: never run `gofmt -w` on this file — it breaks the shebang.
+package main
+
+import (
+	"os"
+
+	"github.com/eSlider/2dph/internal/cmdbin"
+)
+
+func main() {
+	os.Exit(cmdbin.ExecFile("bin/kb/add", os.Args[1:]))
+}

bin/brain/get.go

@@ -8,6 +8,7 @@
 //	./bin/brain/get.go <id> --json
 //
 // Needs CGO + libladybug. Python bin/kb/get is the CI fallback (no cgo).
+// CGO compiler is Zig (`eval "$(bin/cgo/zig env)"`), not gcc.
 // NOTE: never run `gofmt -w` on this file — it breaks the shebang.
 package main
 

bin/brain/index.go

@@ -3,12 +3,12 @@
 //
 // bin/brain/index.go - rebuild the Ladybug graph (Python write path).
 //
-//	./bin/brain/index.go --rebuild
+//	./bin/brain/index.go --rebuild --with-facts --with-chats
 //	./bin/brain/index.go --rebuild --with-mail
 //	./bin/brain/index.go --dry-run --with-mail
 //
-// v1 write is always a rebuild when mail is included (live FTS/HNSW + bulk
+// v1 write: bin/brain/add.go for one/few leafs (indexes may already exist).
-// insert corrupts Ladybug 0.19 WAL). `add` is v2.
+// Bulk mail/corpus still --rebuild (fresh file, indexes last).
 // NOTE: never run `gofmt -w` on this file — it breaks the shebang.
 package main
 

bin/brain/search.go

@@ -3,11 +3,11 @@
 //
 // bin/brain/search.go - deduction search over the 2dph brain.
 //
-//	./bin/brain/search.go "query" [--root facts|info] [--repo P] [-n N] [--json] [--no-web]
+//	./bin/brain/search.go "query" [--root facts|info] [--repo P] [-n N] [--hop N] [--json] [--no-web]
 //	./bin/brain/search.go serve [port]
 //	./bin/brain/search.go --list-model
 //
-// Needs CGO + libladybug (CGO_CFLAGS/CGO_LDFLAGS). Prefer the wrapper
+// Needs CGO + libladybug via Zig (`eval "$(bin/cgo/zig env)"`), not gcc.
 // bin/kb/search which sets those and builds a binary for the embed daemon.
 // NOTE: never run `gofmt -w` on this file — it breaks the shebang.
 package main

bin/cgo/zc++

@@ -0,0 +1,23 @@
+#!/bin/sh
+# bin/cgo/zc++ — CGO CXX. Zig, not g++.
+set -eu
+ROOT="$(CDPATH= cd -- "$(dirname "$0")/../.." && pwd)"
+case "$(uname -m)" in
+  x86_64|amd64) TARGET=x86_64-linux-gnu ;;
+  aarch64|arm64) TARGET=aarch64-linux-gnu ;;
+  *)
+    echo "zc++: unsupported arch $(uname -m)" >&2
+    exit 2
+    ;;
+esac
+if [ -n "${ZIG:-}" ] && [ -x "$ZIG" ]; then
+  :
+elif [ -x "$ROOT/var/zig/zig" ]; then
+  ZIG="$ROOT/var/zig/zig"
+elif command -v zig >/dev/null 2>&1; then
+  ZIG="$(command -v zig)"
+else
+  echo "zc++: zig missing; run bin/cgo/zig first" >&2
+  exit 127
+fi
+exec "$ZIG" c++ -target "$TARGET" "$@"

bin/cgo/zcc

@@ -0,0 +1,24 @@
+#!/bin/sh
+# bin/cgo/zcc — CGO CC. Zig, not gcc.
+# Go invokes CC with many args; a wrapper avoids spaces in $CC.
+set -eu
+ROOT="$(CDPATH= cd -- "$(dirname "$0")/../.." && pwd)"
+case "$(uname -m)" in
+  x86_64|amd64) TARGET=x86_64-linux-gnu ;;
+  aarch64|arm64) TARGET=aarch64-linux-gnu ;;
+  *)
+    echo "zcc: unsupported arch $(uname -m)" >&2
+    exit 2
+    ;;
+esac
+if [ -n "${ZIG:-}" ] && [ -x "$ZIG" ]; then
+  :
+elif [ -x "$ROOT/var/zig/zig" ]; then
+  ZIG="$ROOT/var/zig/zig"
+elif command -v zig >/dev/null 2>&1; then
+  ZIG="$(command -v zig)"
+else
+  echo "zcc: zig missing; run bin/cgo/zig first" >&2
+  exit 127
+fi
+exec "$ZIG" cc -target "$TARGET" "$@"

bin/cgo/zig

@@ -0,0 +1,130 @@
+#!/usr/bin/env bash
+# bin/cgo/zig — CGO toolchain: zig cc (not gcc) + pinned liblbug + libtokenizers.
+#
+#   eval "$(bin/cgo/zig env)"     # export CC/CXX/CGO_*
+#   bin/cgo/zig go build ...      # ensure, then exec with env
+#   bin/cgo/zig ./bin/brain/search.go "query"
+#
+# Pins live in this file. Downloads land in var/ (gitignored).
+set -euo pipefail
+
+ROOT="$(CDPATH= cd -- "$(dirname "$0")/../.." && pwd)"
+ZIG_VERSION=0.14.1
+LBUG_VERSION=0.19.1
+TOKENIZERS_VERSION=1.27.0
+
+arch="$(uname -m)"
+case "$arch" in
+  x86_64|amd64)
+    ZIG_ARCH=x86_64
+    LBUG_ARCH=x86_64
+    TOK_ARCH=x86_64
+    ZIG_SHA=24aeeec8af16c381934a6cd7d95c807a8cb2cf7df9fa40d359aa884195c4716c
+    LBUG_SHA=ed263ae913f68cb0ddba0b98548b58edaac49929766d03bdaaa83be46c68847d
+    TOK_SHA=72556cdca798dd4ea7cdaba308e5f0d68a8cb93b67c96edf485b7a0edd7b07f4
+    ;;
+  aarch64|arm64)
+    ZIG_ARCH=aarch64
+    LBUG_ARCH=aarch64
+    TOK_ARCH=aarch64
+    ZIG_SHA=f7a654acc967864f7a050ddacfaa778c7504a0eca8d2b678839c21eea47c992b
+    LBUG_SHA=b07df2cd533c3976a2a3025866d6420a5f35514d0a822ecc4b2902d55b4725b7
+    TOK_SHA=e96545ad05930c26f51f63d932ee6d3bbd32bbed149e102c5290d587a2293067
+    ;;
+  *)
+    echo "bin/cgo/zig: unsupported arch $arch" >&2
+    exit 2
+    ;;
+esac
+
+CACHE="$ROOT/var/cache"
+LIB="$ROOT/lib-ladybug"
+ZIG_DIR="$ROOT/var/zig-dist"
+ZIG_BIN="$ROOT/var/zig/zig"
+
+sha256of() {
+  if command -v sha256sum >/dev/null 2>&1; then
+    sha256sum "$1" | awk '{print $1}'
+  else
+    shasum -a 256 "$1" | awk '{print $1}'
+  fi
+}
+
+fetch() {
+  local url="$1" dest="$2" expect="$3"
+  if [ -f "$dest" ] && [ "$(sha256of "$dest")" = "$expect" ]; then
+    return 0
+  fi
+  mkdir -p "$(dirname "$dest")"
+  echo "fetch $url" >&2
+  curl -fsSL "$url" -o "$dest"
+  local got
+  got="$(sha256of "$dest")"
+  if [ "$got" != "$expect" ]; then
+    echo "checksum mismatch $dest: got $got want $expect" >&2
+    rm -f "$dest"
+    exit 1
+  fi
+}
+
+ensure_zig() {
+  if [ -n "${ZIG:-}" ] && [ -x "$ZIG" ]; then
+    return 0
+  fi
+  if [ -x "$ZIG_BIN" ]; then
+    export ZIG="$ZIG_BIN"
+    return 0
+  fi
+  if command -v zig >/dev/null 2>&1; then
+    export ZIG
+    ZIG="$(command -v zig)"
+    return 0
+  fi
+  local tar="$CACHE/zig-${ZIG_ARCH}-linux-${ZIG_VERSION}.tar.xz"
+  fetch "https://ziglang.org/download/${ZIG_VERSION}/zig-${ZIG_ARCH}-linux-${ZIG_VERSION}.tar.xz" \
+    "$tar" "$ZIG_SHA"
+  mkdir -p "$CACHE"
+  rm -rf "$ZIG_DIR"
+  tar -xJf "$tar" -C "$CACHE"
+  mv "$CACHE/zig-${ZIG_ARCH}-linux-${ZIG_VERSION}" "$ZIG_DIR"
+  mkdir -p "$ROOT/var/zig"
+  ln -sfn "$ZIG_DIR/zig" "$ZIG_BIN"
+  export ZIG="$ZIG_BIN"
+}
+
+ensure_libs() {
+  mkdir -p "$LIB"
+  if [ ! -f "$LIB/liblbug.so" ]; then
+    local tar="$CACHE/liblbug-linux-${LBUG_ARCH}.tar.gz"
+    fetch "https://github.com/LadybugDB/ladybug/releases/download/v${LBUG_VERSION}/liblbug-linux-${LBUG_ARCH}.tar.gz" \
+      "$tar" "$LBUG_SHA"
+    tar -xzf "$tar" -C "$LIB"
+  fi
+  if [ ! -f "$LIB/libtokenizers.a" ]; then
+    local tar="$CACHE/libtokenizers.linux-${TOK_ARCH}.tar.gz"
+    fetch "https://github.com/daulet/tokenizers/releases/download/v${TOKENIZERS_VERSION}/libtokenizers.linux-${TOK_ARCH}.tar.gz" \
+      "$tar" "$TOK_SHA"
+    tar -xzf "$tar" -C "$LIB"
+  fi
+}
+
+print_env() {
+  printf 'export ZIG=%q\n' "$ZIG"
+  printf 'export CC=%q\n' "$ROOT/bin/cgo/zcc"
+  printf 'export CXX=%q\n' "$ROOT/bin/cgo/zc++"
+  printf 'export CGO_ENABLED=1\n'
+  printf 'export CGO_CFLAGS=%q\n' "-I$LIB"
+  printf 'export CGO_LDFLAGS=%q\n' "-L$LIB -Wl,-rpath,${CGO_RPATH:-$LIB}"
+}
+
+ensure_zig
+ensure_libs
+
+cmd="${1:-env}"
+if [ "$cmd" = "env" ]; then
+  print_env
+  exit 0
+fi
+
+eval "$(print_env)"
+exec "$@"

bin/chats/sync.go

@@ -29,10 +29,11 @@ func main() {
 	case "linkedin":
 		os.Exit(chats.RunSyncLinkedIn(args))
 	case "whatsapp":
-		fmt.Fprintln(os.Stderr, "chats: WhatsApp not implemented yet")
+		fmt.Fprintln(os.Stderr, "chats: WhatsApp sync is out of v1")
 		os.Exit(1)
 	case "help", "-h", "--help":
-		fmt.Fprintln(os.Stderr, `usage: bin/chats/sync.go telegram|linkedin [flags]`)
+		fmt.Fprintln(os.Stderr, `usage: bin/chats/sync.go telegram|linkedin [flags]
+WhatsApp sync is out of v1.`)
 		return
 	default:
 		fmt.Fprintf(os.Stderr, "chats: unknown platform %q\n", platform)

bin/cli/complete.go

@@ -0,0 +1,91 @@
+//usr/bin/env go run "$0" "$@"; exit
+//
+// bin/cli/complete.go - dump flaggy shell completions for all Go shebang tools (D23).
+//
+//	source <(./bin/cli/complete.go bash)
+//	./bin/cli/complete.go zsh|fish|powershell|nushell
+//
+// Search does not steal the word "completion"; this binary dumps scripts.
+// NOTE: never run `gofmt -w` on this file — it breaks the shebang.
+package main
+
+import (
+	"fmt"
+	"os"
+	"strings"
+
+	mailsync "github.com/eSlider/2dph/bin/mail/sync"
+	"github.com/eSlider/2dph/internal/brain/rank"
+	"github.com/eSlider/2dph/internal/chats"
+	"github.com/eSlider/2dph/internal/cli"
+	"github.com/eSlider/2dph/internal/gitlog"
+	"github.com/eSlider/2dph/internal/mdleaves"
+	"github.com/eSlider/2dph/internal/ocr"
+	"github.com/eSlider/2dph/internal/reasoner"
+	"github.com/eSlider/2dph/internal/websearch"
+	"github.com/integrii/flaggy"
+)
+
+func tools() []cli.Tool {
+	return []cli.Tool{
+		{Path: "bin/brain/search.go", Name: "brain-search", New: rank.Parser},
+		{Path: "bin/brain/get.go", Name: "brain-get", New: func() *flaggy.Parser {
+			o := rank.GetOptions{}
+			return rank.GetParser(&o)
+		}},
+		{Path: "bin/brain/stats.go", Name: "brain-stats", New: rank.StatsParser},
+		{Path: "bin/brain/eval.go", Name: "brain-eval", New: rank.EvalParser},
+		{Path: "bin/web/search.go", Name: "web-search", New: websearch.Parser},
+		{Path: "bin/git/import.go", Name: "git-import", New: gitlog.Parser},
+		{Path: "bin/markdown/import.go", Name: "markdown-import", New: mdleaves.Parser},
+		{Path: "bin/qa/stats.go", Name: "qa-stats", New: cli.QAParser},
+		{Path: "bin/reasoner/bakeoff.go", Name: "reasoner-bakeoff", New: reasoner.Parser},
+		{Path: "bin/mail/ocr.go", Name: "mail-ocr", New: ocr.Parser},
+		{Path: "bin/mail/sync.go", Name: "mail-sync", New: mailsync.Parser},
+		{Path: "bin/chats/sync.go", Name: "chats-sync", New: chats.SyncParser},
+		{Path: "bin/chats/import.go", Name: "chats-import", New: chats.ImportParser},
+		{Path: "bin/chats/facts.go", Name: "chats-facts", New: chats.FactsParser},
+		{Path: "bin/chats/apply.go", Name: "chats-apply", New: chats.ApplyParser},
+	}
+}
+
+func main() {
+	os.Exit(run(os.Args[1:]))
+}
+
+func run(args []string) int {
+	shell := "bash"
+	if len(args) > 0 {
+		switch args[0] {
+		case "bash", "zsh", "fish", "powershell", "nushell":
+			shell = args[0]
+		case "-h", "--help", "help":
+			fmt.Fprintln(os.Stderr, "usage: bin/cli/complete.go [bash|zsh|fish|powershell|nushell]")
+			return 0
+		default:
+			fmt.Fprintf(os.Stderr, "cli/complete: unknown shell %q\n", args[0])
+			return 2
+		}
+	}
+	if shell == "bash" {
+		fmt.Print(cli.BashScript(tools()))
+		return 0
+	}
+	var b strings.Builder
+	for _, t := range tools() {
+		p := t.New()
+		p.Name = t.Name
+		switch shell {
+		case "zsh":
+			b.WriteString(flaggy.GenerateZshCompletion(p))
+		case "fish":
+			b.WriteString(flaggy.GenerateFishCompletion(p))
+		case "powershell":
+			b.WriteString(flaggy.GeneratePowerShellCompletion(p))
+		case "nushell":
+			b.WriteString(flaggy.GenerateNushellCompletion(p))
+		}
+	}
+	fmt.Print(b.String())
+	return 0
+}

bin/docker-entrypoint

@@ -1,13 +1,10 @@
 #!/usr/bin/env bash
 # bin/docker-entrypoint - run 2dph tools inside the container.
 #
-#   brain                 shell (default)
+# API image (Zig CGO binaries):
-#   brain search <q>      bin/brain/search.go
+#   serve | search | watch
-#   brain index           bin/kb/index --with-mail
+# Index image (Python write path, compose profile `index`):
-#   brain watch <dir>     compiled /app/bin/watch (bin/brain/watch.go)
+#   index | extract | audit | search (deprecated python wrapper)
-#   brain serve           compiled /app/bin/serve (bin/brain/serve.go)
-#   brain extract         bin/facts/extract (docker×compose pairing)
-#   brain audit           bin/facts/audit
 #
 # Usage comment starts at line 2 (self-describing convention).
 set -euo pipefail
@@ -15,6 +12,20 @@ set -euo pipefail
 CMD="${1:-shell}"
 shift || true
 
+if [ -x /usr/local/bin/brain-serve ]; then
+	case "$CMD" in
+		shell) exec bash ;;
+		serve) exec /usr/local/bin/brain-serve "$@" ;;
+		search) exec /usr/local/bin/brain-search "$@" ;;
+		watch) exec /usr/local/bin/brain-watch "$@" ;;
+		index)
+			echo "index is the Python sidecar: docker compose --profile index run --rm index" >&2
+			exit 2
+			;;
+		*) echo "unknown command: $CMD (api: serve|search|watch)" >&2; exit 2 ;;
+	esac
+fi
+
 case "$CMD" in
 	shell) exec bash ;;
 	search) exec "$KB_PY" /app/bin/kb/search "$@" ;;

bin/facts/audit

@@ -1,14 +1,15 @@
 #!/usr/bin/env python3
 """facts/audit - evidence & lexicon checks for the 2dph brain.
 
-  bin/facts/audit self      # lexicon: every fact in db has >=2 sources
+  bin/facts/audit self         # lexicon: docs + two-source rule
-  bin/facts/audit db        # evidence gate: run against var/kb.lbug
+  bin/facts/audit db           # evidence gate against var/kb.lbug
+  bin/facts/audit contradict   # D16 adjudication (JSON claim(s) on stdin)
 
-`self` mode checks the repo itself (no network, no runtime deps). It greps
+`self` mode checks the repo itself (no network, no runtime deps).
-for known-good two-source pairings and confirms the docs are consistent.
+`db` mode loads every Leaf with root=facts. Confirmed facts need ` x `;
-`db` mode loads every Leaf with root=facts and asserts each has source_rev
+hypothesis contradictions need `a x b vs c x d` (both sides ≥2).
-and a non-empty `loc` (the "where did you see it" evidence pointer) and that
+`contradict` applies temporal_freshness then authority_pairing; ≥2 vs ≥2
-'confirmed' facts carry a two-source `source` field.
+with no rule stays hypothesis / `(not confirmed)`.
 
 Exit 0 = all checks pass, 1 = audit failures, 2 = could not evaluate.
 """
@@ -22,6 +23,8 @@ from pathlib import Path
 ROOT = Path(__file__).resolve().parents[2]
 sys.path.insert(0, str(ROOT / "bin" / "tools"))
 
+from contradict import adjudicate, check_fact_row  # noqa: E402
+
 
 def audit_db() -> list[str]:
     from kblib import connect
@@ -33,14 +36,8 @@ def audit_db() -> list[str]:
     r = conn.execute("MATCH (l:Leaf {root:'facts'}) RETURN l.id, l.source, l.loc, l.how, l.confidence")
     problems: list[str] = []
     for lid, source, loc, how, conf in r.get_all():
-        if conf != "confirmed":
+        problems.extend(check_fact_row(str(lid), str(source or ""), str(loc or ""),
-            problems.append(f"{lid}: facts require confidence='confirmed', got '{conf}'")
+                                       str(how or ""), str(conf or "")))
-        if not source or " x " not in source:
-            problems.append(f"{lid}: needs 2-source evidence in source, got '{source}'")
-        if not loc:
-            problems.append(f"{lid}: missing loc (evidence pointer)")
-        if not how:
-            problems.append(f"{lid}: missing how")
     conn.close()
     db.close()
     return problems
@@ -54,20 +51,50 @@ def audit_self() -> list[str]:
         problems.append("PLAN.md missing recall@5 gate")
     if re.search(r"(?i)facts must have.*2 sources|2.source", plan) is None:
         problems.append("PLAN.md missing the two-source evidence rule for facts")
+    if "temporal_freshness" not in plan or "authority_pairing" not in plan:
+        problems.append("PLAN.md missing D16 adjudication rules")
     if re.search(r"(?i)HNSW|BM25|deduction", (ROOT / "README.md").read_text()) is None:
         problems.append("README.md missing search/retrieval description")
     return problems
 
 
+def audit_contradict(raw: str) -> tuple[list[str], list[dict]]:
+    raw = raw.strip()
+    if not raw:
+        return ["contradict: empty stdin (JSON claim or {claims:[...]})"], []
+    try:
+        payload = json.loads(raw)
+    except json.JSONDecodeError as e:
+        return [f"contradict: invalid JSON: {e}"], []
+    if isinstance(payload, dict) and "claims" in payload:
+        claims = list(payload.get("claims") or [])
+    elif isinstance(payload, dict):
+        claims = [payload]
+    elif isinstance(payload, list):
+        claims = payload
+    else:
+        return ["contradict: expected object or list"], []
+    details = [adjudicate(c) for c in claims]
+    return [], details
+
+
 def main(argv: list[str]) -> int:
     import argparse
     p = argparse.ArgumentParser(description="evidence & lexicon audit")
-    p.add_argument("mode", choices=("self", "db"))
+    p.add_argument("mode", choices=("self", "db", "contradict"))
     p.add_argument("--json", action="store_true")
     a = p.parse_args(argv)
 
-    problems = audit_self() if a.mode == "self" else audit_db()
+    details: list[dict] = []
-    out = {"mode": a.mode, "ok": not problems, "problems": problems}
+    if a.mode == "self":
+        problems = audit_self()
+    elif a.mode == "db":
+        problems = audit_db()
+    else:
+        problems, details = audit_contradict(sys.stdin.read())
+    out: dict = {"mode": a.mode, "ok": not problems, "problems": problems}
+    if details:
+        out["contradictions"] = details
     if a.json:
         print(json.dumps(out, indent=2))
     else:

bin/facts/audit.go

@@ -5,6 +5,7 @@
 //
 //	./bin/facts/audit.go self
 //	./bin/facts/audit.go db
+//	./bin/facts/audit.go contradict --json < claim.json
 //
 // Python bin/facts/audit is the implementation (CI runs it directly).
 // NOTE: never run `gofmt -w` on this file — it breaks the shebang.

bin/git/import.go

@@ -16,9 +16,8 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
-	"strconv"
-	"time"
 
+	cliparse "github.com/eSlider/2dph/internal/cli"
 	"github.com/eSlider/2dph/internal/cmdbin"
 	"github.com/eSlider/2dph/internal/gitlog"
 )
@@ -28,50 +27,17 @@ func main() {
 }
 
 func run(args []string) int {
-	var repo, root, since string
+	c, err := gitlog.ParseArgs(args)
-	limit := 0
+	if err != nil {
-	jsonOut := false
+		return cliparse.Fail(err)
-	i := 0
-	for i < len(args) {
-		a := args[i]
-		switch {
-		case a == "--json":
-			jsonOut = true
-		case a == "--limit" && i+1 < len(args):
-			i++
-			n, err := strconv.Atoi(args[i])
-			if err != nil || n < 0 {
-				fmt.Fprintf(os.Stderr, "git/import: --limit must be a non-negative integer\n")
-				return 2
-			}
-			limit = n
-		case a == "--since" && i+1 < len(args):
-			i++
-			since = args[i]
-		case a == "--root" && i+1 < len(args):
-			i++
-			root = args[i]
-		case a == "-h" || a == "--help":
-			fmt.Fprintln(os.Stderr, `usage: bin/git/import.go [REPO] [--json] [--limit N] [--since DATE] [--root DIR]`)
-			return 0
-		case len(a) > 0 && a[0] != '-':
-			repo = a
-		default:
-			fmt.Fprintf(os.Stderr, "git/import: unknown flag %s\n", a)
-			return 2
-		}
-		i++
 	}
+	repo, root, since, limit, jsonOut := c.Repo, c.Root, c.Since, c.Limit, c.JSONOut
 
-	var sinceT time.Time
+	sinceT, err := gitlog.ParseSince(since)
-	if since != "" {
-		var err error
-		sinceT, err = parseSince(since)
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "git/import: %v\n", err)
 		return 2
 	}
-	}
 
 	repos := []string{}
 	if repo != "" {
@@ -132,12 +98,3 @@ func run(args []string) int {
 	}
 	return 0
 }
-
-func parseSince(s string) (time.Time, error) {
-	for _, layout := range []string{time.RFC3339, "2006-01-02"} {
-		if t, err := time.Parse(layout, s); err == nil {
-			return t, nil
-		}
-	}
-	return time.Time{}, fmt.Errorf("cannot parse --since %q", s)
-}

bin/kb/add

@@ -0,0 +1,120 @@
+#!/usr/bin/env python3
+"""kb/add - incremental leaf write (no rebuild).
+
+  bin/kb/add --text T --root facts|info --source S
+  bin/kb/add --json                 # stdin: one object or {"leafs":[...]}
+  bin/kb/add --db PATH --json
+
+Writes facts+info in one Ladybug transaction. Does not delete kb.lbug.
+Embedding is used when provided; otherwise model2vec encodes the text.
+"""
+from __future__ import annotations
+
+import json
+import sys
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parents[2]
+sys.path.insert(0, str(ROOT / "bin" / "tools"))
+
+from kblib import (  # noqa: E402
+    EMBED_DIM,
+    add_leafs,
+    connect,
+    ensure_indexes,
+    init_schema,
+)
+
+
+def _as_leafs(payload: object) -> list[dict]:
+    if isinstance(payload, list):
+        return [dict(x) for x in payload]
+    if isinstance(payload, dict):
+        if "leafs" in payload:
+            return [dict(x) for x in payload["leafs"]]
+        return [dict(payload)]
+    raise ValueError("json must be an object, a list, or {leafs:[...]}")
+
+
+def _embed_missing(leafs: list[dict]) -> None:
+    missing = [lf for lf in leafs if not lf.get("embedding")]
+    if not missing:
+        return
+    from model2vec import StaticModel
+
+    model = StaticModel.from_pretrained("minishlab/potion-multilingual-128M")
+    for lf in missing:
+        text = str(lf.get("text") or "")
+        vec = model.encode([text])[0].astype(float).tolist()
+        if len(vec) != EMBED_DIM:
+            vec = (vec + [0.0] * EMBED_DIM)[:EMBED_DIM]
+        lf["embedding"] = vec
+
+
+def main(argv: list[str]) -> int:
+    import argparse
+
+    p = argparse.ArgumentParser(description="add leafs without rebuilding the brain")
+    p.add_argument("--db", default="", help="path to kb.lbug (default var/kb.lbug)")
+    p.add_argument("--json", action="store_true", help="read leaf JSON from stdin")
+    p.add_argument("--text", default="", help="leaf text")
+    p.add_argument("--root", default="info", choices=("facts", "info"))
+    p.add_argument("--source", default="")
+    p.add_argument("--confidence", default="confirmed")
+    p.add_argument("--source-rev", default="working-tree")
+    p.add_argument("--how", default="brain/add")
+    p.add_argument("--loc", default="")
+    p.add_argument("--type", default="reference", dest="type_")
+    p.add_argument("--valid-from", default="", dest="valid_from",
+                   help="fact interval start YYYY-MM-DD (D24)")
+    p.add_argument("--valid-to", default="", dest="valid_to",
+                   help="fact interval end YYYY-MM-DD inclusive; empty=open (D24)")
+    args = p.parse_args(argv)
+
+    if args.json:
+        raw = sys.stdin.read()
+        if not raw.strip():
+            print("kb/add: empty stdin", file=sys.stderr)
+            return 2
+        leafs = _as_leafs(json.loads(raw))
+    else:
+        if not args.text or not args.source:
+            print("kb/add: --text and --source are required (or --json)", file=sys.stderr)
+            return 2
+        leafs = [{
+            "text": args.text,
+            "root": args.root,
+            "source": args.source,
+            "confidence": args.confidence,
+            "source_rev": args.source_rev,
+            "how": args.how,
+            "loc": args.loc or args.source,
+            "type": args.type_,
+            "valid_from": args.valid_from,
+            "valid_to": args.valid_to,
+        }]
+
+    for lf in leafs:
+        if not lf.get("text") or not lf.get("source"):
+            print("kb/add: each leaf needs text and source", file=sys.stderr)
+            return 2
+
+    _embed_missing(leafs)
+
+    from kblib import DB_PATH, VAR
+
+    dbpath = Path(args.db) if args.db else DB_PATH
+    dbpath.parent.mkdir(parents=True, exist_ok=True)
+    VAR.mkdir(exist_ok=True)
+    db, conn = connect(dbpath, read_only=False)
+    init_schema(conn)
+    ids = add_leafs(conn, leafs)
+    ensure_indexes(conn)
+    conn.close()
+    db.close()
+    print(json.dumps({"mode": "add", "ids": ids, "db": str(dbpath)}))
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main(sys.argv[1:]))

bin/kb/index

@@ -2,12 +2,15 @@
 """kb/index - build the 2dph brain from markdown + factual leafs.
 
   bin/kb/index [--corpus DIR] [--rebuild] [--limit N]
+  bin/kb/index --rebuild --with-facts --with-chats
   bin/kb/index --json                 # emit stats as JSON
 
 Reads every .md under the corpus (default: repo root docs, skills, READMEs)
 as `info` leafs, embeds them with model2vec (potion-multilingual-128M), and
 writes them into var/kb.lbug with FTS + HNSW indexes. `facts` leafs come
-from bin/facts/extract (docker x compose x ssh-config pairing).
+from bin/facts/extract (docker × compose × ssh-config pairing) when
+`--with-facts` is set. `--with-chats` indexes markdown under var/chats/md
+(or a given dir) as info. WhatsApp sync stays out of v1.
 
 --rebuild drops the database file and indexes from scratch. Without it a run
 is idempotent (MERGE by (source,text) id).
@@ -22,7 +25,7 @@ ROOT = Path(__file__).resolve().parents[2]
 sys.path.insert(0, str(ROOT / "bin" / "tools"))
 
 from kblib import (  # noqa: E402
-    connect, ensure_indexes, init_schema, upsert_leaf,
+    add_leafs, connect, ensure_indexes, init_schema, upsert_leaf, link_from_file,
     open_readonly, stats,
 )
 from mdleaves import read_markdown, to_all, walk_markdown  # noqa: E402
@@ -81,10 +84,11 @@ def index_leafs(conn, leafs: list[dict], embed_fn, limit: int) -> tuple[int, int
     for lf in leafs[:limit] if limit else leafs:
         query = f"{lf['heading']}\n\n{lf['text']}"
         emb = embed_fn(lf["text"]) if lf["text"] else None
-        upsert_leaf(conn, text=query, root="info", confidence="confirmed",
+        lid = upsert_leaf(conn, text=query, root="info", confidence="confirmed",
                     source=lf["source"], source_rev="working-tree",
                     how="kb/index", loc=lf["source"], type_=lf.get("type", "reference"),
                     embedding=emb)
+        link_from_file(conn, lid, lf["source"], repo=str(lf.get("repo") or ""))
         count += 1
     return count, len(leafs)
 
@@ -95,12 +99,65 @@ def embedder():
     return lambda text: model.encode([text])[0].astype(float).tolist()
 
 
+def index_fact_dicts(conn, facts: list[dict], embed_fn) -> int:
+    """Write extract-shaped dicts as root=facts leafs (2-source source field)."""
+    leafs = []
+    for f in facts:
+        text = str(f.get("text") or "")
+        source = str(f.get("source") or "")
+        if not text or not source:
+            continue
+        leafs.append({
+            "text": text,
+            "root": "facts",
+            "confidence": "confirmed",
+            "source": source,
+            "source_rev": f.get("source_rev") or "working-tree",
+            "how": f.get("how") or "facts/extract",
+            "loc": f.get("loc") or source,
+            "type": "fact",
+            "embedding": embed_fn(text) if text else None,
+        })
+    return len(add_leafs(conn, leafs))
+
+
+def facts_from_extract() -> list[dict]:
+    import subprocess
+    proc = subprocess.run(
+        [sys.executable, str(ROOT / "bin" / "facts" / "extract"), "--json", "--dry-run"],
+        cwd=ROOT,
+        capture_output=True,
+        text=True,
+        check=False,
+    )
+    if proc.returncode != 0:
+        print(f"kb/index: facts/extract failed: {proc.stderr}", file=sys.stderr)
+        return []
+    try:
+        payload = json.loads(proc.stdout)
+    except json.JSONDecodeError:
+        print("kb/index: facts/extract produced non-JSON", file=sys.stderr)
+        return []
+    return list(payload.get("facts") or [])
+
+
 def main(argv: list[str]) -> int:
     import argparse
     p = argparse.ArgumentParser(description="build the 2dph brain index")
     p.add_argument("--corpus", action="append", help="extra markdown dir/file to index (may repeat)")
     p.add_argument("--rebuild", action="store_true", help="fresh db + indexes")
+    p.add_argument("--db", default="", help="path to kb.lbug (default var/kb.lbug)")
+    p.add_argument("--no-defaults", action="store_true", help="do not index repo README/docs/skills")
     p.add_argument("--with-mail", action="store_true", help="include var/mail message.md leafs")
+    p.add_argument("--with-facts", action="store_true", help="run facts/extract into root=facts")
+    p.add_argument("--facts-json", default="", help="JSON list (or {facts:[...]}) of fact dicts")
+    p.add_argument(
+        "--with-chats",
+        nargs="?",
+        const=str(ROOT / "var" / "chats" / "md"),
+        default="",
+        help="index chat markdown as info (default var/chats/md)",
+    )
     p.add_argument("--since", default="", help="with --with-mail, only messages dated >= YYYY-MM-DD")
     p.add_argument("--dry-run", action="store_true", help="count leafs, write nothing")
     p.add_argument(
@@ -114,44 +171,71 @@ def main(argv: list[str]) -> int:
 
     from kblib import DB_PATH, VAR
 
-    leafs = load_corpus(ROOT)
+    dbpath = Path(a.db) if a.db else DB_PATH
+    leafs: list[dict] = [] if a.no_defaults else load_corpus(ROOT)
     if a.corpus:
         for source in a.corpus:
             leafs.extend(load_corpus_glob(source))
+    chat_n = 0
+    if a.with_chats:
+        chats = load_corpus_glob(a.with_chats)
+        chat_n = len(chats)
+        leafs.extend(chats)
     mail_n = 0
     if a.with_mail:
         mail = from_mail_root(ROOT / "var" / "mail", since=a.since)
         mail_n = len(mail)
         leafs.extend(mail)
 
+    facts: list[dict] = []
+    if a.facts_json:
+        raw = Path(a.facts_json).read_text(encoding="utf-8")
+        payload = json.loads(raw)
+        facts = list(payload.get("facts") if isinstance(payload, dict) else payload)
+    if a.with_facts:
+        facts.extend(facts_from_extract())
+
     if a.dry_run:
-        msg = {"indexed": 0, "corpus_total": len(leafs), "mail_leafs": mail_n, "dry_run": True}
+        msg = {
+            "indexed": 0,
+            "corpus_total": len(leafs),
+            "mail_leafs": mail_n,
+            "chat_leafs": chat_n,
+            "facts_leafs": len(facts),
+            "dry_run": True,
+        }
         print(json.dumps(msg, indent=2) if a.json else
-              f"brain/index: {len(leafs)} leafs would be indexed (mail={mail_n})")
+              f"brain/index: {len(leafs)} info + {len(facts)} facts would be indexed")
         return 0
 
     VAR.mkdir(exist_ok=True)
-    if a.rebuild and DB_PATH.exists():
+    dbpath.parent.mkdir(parents=True, exist_ok=True)
-        DB_PATH.unlink()
+    if a.rebuild and dbpath.exists():
+        dbpath.unlink()
 
-    db, conn = connect(DB_PATH, read_only=False)
+    db, conn = connect(dbpath, read_only=False)
     init_schema(conn)
 
-    # Never DROP FTS/VECTOR (ghost catalog). Write leafs, then ensure indexes
-    # unless --skip-indexes (seed facts first — MERGE under live FTS corrupts it).
-    # --rebuild already deleted kb.lbug above, so CREATE runs on a clean DB.
     embed = embedder()
     done, total = index_leafs(conn, leafs, embed, a.limit)
+    fact_n = index_fact_dicts(conn, facts, embed) if facts else 0
     if not a.skip_indexes:
         ensure_indexes(conn)
     s = stats(conn)
     conn.close()
     db.close()
 
-    result = {"indexed": done, "corpus_total": total, **{k: v for k, v in s.items() if k in ("total", "by_root")}}
+    result = {
+        "indexed": done,
+        "corpus_total": total,
+        "facts_leafs": fact_n,
+        "chat_leafs": chat_n,
+        **{k: v for k, v in s.items() if k in ("total", "by_root")},
+    }
     if a.skip_indexes:
         result["indexes"] = "skipped"
-    print(json.dumps(result, indent=2) if a.json else f"indexed {done}/{total} leafs; db total {s['total']}")
+    print(json.dumps(result, indent=2) if a.json else
+          f"indexed {done}/{total} info + {fact_n} facts; db total {s['total']}")
     return 0
 
 

bin/kb/search

@@ -1,10 +1,9 @@
 #!/usr/bin/env bash
 # bin/kb/search — deprecated wrapper. Use bin/brain/search.go.
-# Sets CGO for ladybug, builds a binary (embed daemon needs a real executable),
+# CGO via Zig (bin/cgo/zig), not gcc. Builds a binary then execs it.
-# then execs it. Prints one deprecation line.
 set -euo pipefail
 
-ROOT="$(cd "$(dirname "$0")/../.." && pwd)"
+ROOT="$(CDPATH= cd -- "$(dirname "$0")/../.." && pwd)"
 BIN="$ROOT/var/bin/brain-search"
 SRC="$ROOT/internal/brain"
 CMD="$ROOT/bin/brain"
@@ -24,11 +23,10 @@ else
 fi
 
 if [ "$need_build" -eq 1 ]; then
-	echo "Building brain/search..." >&2
+	echo "Building brain/search (zig cc)..." >&2
 	(
 		cd "$ROOT" &&
-			CGO_CFLAGS="-I$ROOT/lib-ladybug" \
+			eval "$("$ROOT/bin/cgo/zig" env)" &&
-			CGO_LDFLAGS="-L$ROOT/lib-ladybug -Wl,-rpath,$ROOT/lib-ladybug" \
 			go build -tags system_ladybug -o "$BIN" ./bin/brain
 	) || exit 1
 fi

bin/mail/import

@@ -7,7 +7,7 @@
   bin/mail/import --since 2026-01-01    only messages after a date
   bin/mail/import --limit 50            cap messages per run
   bin/mail/import --no-attachments      body only, skip attachment conversion
-  bin/mail/import --ocr                OCR scanned PDFs/images via docling
+  bin/mail/import --ocr                OCR images (PDFs OCR when textless)
   bin/mail/import --dry-run            list messages without writing anything
 
 Writes one directory per message: var/mail/{folder}/{message_id}/
@@ -16,10 +16,11 @@ Writes one directory per message: var/mail/{folder}/{message_id}/
   attachments/*.md          converted attachment content
 
 Indexing is a separate step (`bin/brain/index.go --rebuild`): conversion can
-crash in native docling and must not leave the brain DB mid-transaction.
+crash and must not leave the brain DB mid-transaction.
 
-Requires ONLYOFFICE_URL/USER/PASS in .env (or env). Idempotent: a message
+Requires ONLYOFFICE_URL/USER/PASS in .env (or env) except `--from-raw`.
-already present (message.md exists) is skipped unless --force.
+Idempotent: a message already present (message.md exists) is skipped unless
+--force.
 """
 from __future__ import annotations
 
@@ -41,10 +42,10 @@ from mailconv import (  # noqa: E402
     IMAGE_SUFFIXES,
     LEGACY_OFFICE_SUFFIXES,
     TEXT_SUFFIXES,
+    convert_pdf,
     html_to_markdown,
-    is_convertible,
     normalize_markdown,
-    subject_to_filename,
+    ocr_image,
     zip_extract_safe,
 )
 
@@ -147,9 +148,9 @@ def convert_file_to_md(path: Path, ocr: bool) -> str | None:
         except Exception as e:
             return f"\n<!-- conversion failed: {e} -->\n"
     if suffix == ".pdf":
-        return _convert_pdf(path, ocr)
+        return convert_pdf(path, ocr)
     if suffix in IMAGE_SUFFIXES and ocr:
-        return _convert_pdf(path, ocr)
+        return ocr_image(path) or "\n<!-- ocr unavailable -->\n"
     if suffix in LEGACY_OFFICE_SUFFIXES:
         return _convert_legacy(path)
     if suffix in ARCHIVE_SUFFIXES:
@@ -157,67 +158,6 @@ def convert_file_to_md(path: Path, ocr: bool) -> str | None:
     return None
 
 
-def _convert_pdf(path: Path, ocr: bool) -> str:
-    """Convert one PDF to markdown.
-
-    Fast path: poppler's pdftotext (-layout) extracts exact text from
-    born-digital PDFs in ~15ms vs docling's 1-3s. Only textless PDFs (scanned
-    pages, layout-heavy) fall back to docling, which runs isolated in a
-    subprocess because its native onnx/RT-DETR has segfaulted the main process.
-    """
-    text = _pdf_fast_text(path)
-    if ocr or text is None or not text.strip():
-        return _convert_pdf_docling(path, ocr)
-    return normalize_markdown(text)
-
-
-def _pdf_fast_text(path: Path) -> str | None:
-    """pdftotext -layout; None when poppler is unavailable (or the PDF has no text layer)."""
-    try:
-        proc = subprocess.run(
-            ["pdftotext", "-layout", str(path), "-"],
-            capture_output=True, timeout=60)
-    except (OSError, subprocess.TimeoutExpired):
-        return None
-    if proc.returncode != 0:
-        return None
-    return proc.stdout.decode("utf-8", errors="replace")
-
-
-def _convert_pdf_docling(path: Path, ocr: bool) -> str:
-    try:
-        proc = subprocess.run(
-            [sys.executable, os.path.abspath(__file__), "--pdf-worker", str(path),
-             "--ocr" if ocr else "--no-ocr"],
-            capture_output=True, text=True, timeout=600)
-    except subprocess.TimeoutExpired:
-        return "\n<!-- pdf conversion timed out -->\n"
-    if proc.returncode != 0:
-        tail = proc.stderr.strip().splitlines()[-3:]
-        return f"\n<!-- pdf conversion failed: {proc.returncode}: {' | '.join(tail)} -->\n"
-    return proc.stdout
-
-
-def _pdf_worker(path: Path, ocr: bool) -> None:
-    """docling worker entry: prints converted markdown on stdout, exits non-zero on error."""
-    try:
-        from docling.document_converter import DocumentConverter, PdfFormatOption
-        from docling.datamodel.pipeline_options import PdfPipelineOptions
-        opts = PdfPipelineOptions()
-        opts.do_ocr = bool(ocr)
-        opts.do_table_structure = True
-        conv = DocumentConverter(format_options={"pdf": PdfFormatOption(pipeline_options=opts)})
-        res = conv.convert(str(path))
-        sys.stdout.write(normalize_markdown(res.document.export_to_markdown()))
-        sys.exit(0)
-    except Exception as e:
-        # errors/stacktraces to stderr; the caller only reports a one-liner
-        print(f"pdf-worker: {e}", file=sys.stderr)
-        import traceback
-        traceback.print_exc(file=sys.stderr)
-        sys.exit(1)
-
-
 def _convert_legacy(path: Path) -> str:
     """Legacy .doc/.xls/.ppt -> md via pandoc (installed) or a stub."""
     try:
@@ -356,19 +296,12 @@ def main(argv: list[str]) -> int:
     p.add_argument("--from-raw", default="",
                    help="convert Go-synced dirs (var/mail/<folder>/<id>/message.json) to markdown")
     p.add_argument("--no-attachments", action="store_true", help="skip attachment download+convert")
-    p.add_argument("--ocr", action="store_true", help="OCR scanned PDFs/images via docling")
+    p.add_argument("--ocr", action="store_true", help="OCR images (PDFs OCR when textless)")
     p.add_argument("--force", action="store_true", help="re-import even if message.md exists")
     p.add_argument("--dry-run", action="store_true", help="list messages, write nothing")
     p.add_argument("--json", action="store_true")
-    p.add_argument("--pdf-worker", default="", help=argparse.SUPPRESS)
-    p.add_argument("--no-ocr", action="store_true", help=argparse.SUPPRESS)
     a = p.parse_args(argv)
 
-    if a.pdf_worker:
-        _pdf_worker(Path(a.pdf_worker), ocr=not a.no_ocr)
-        return 0
-
-    conf = load_env()
     fid = folder_id(a.folder)
     out_root = ROOT / "var" / "mail"
     summary: list[dict] = []
@@ -394,6 +327,7 @@ def main(argv: list[str]) -> int:
                                      target_dir=msg_dir.parent))
             summary.append(entry)
     else:
+        conf = load_env()
         OOCLIENT = OOClient(conf)
         if a.id:
             messages = [{"id": i} for i in a.id]

bin/mail/ocr.go

@@ -0,0 +1,46 @@
+//usr/bin/env go run -tags=mail_ocr "$0" "$@"; exit
+//go:build mail_ocr
+//
+// bin/mail/ocr.go - OCR an image or scanned PDF (tesseract eng+deu).
+//
+//	./bin/mail/ocr.go scan.png
+//	./bin/mail/ocr.go scan.pdf
+//	OCR_ENGINE=paddle ./bin/mail/ocr.go scan.png
+//
+// PDFs try pdftotext -layout first; empty text layer uses pdftoppm + tesseract.
+// No gocv. Tesseract CGO bindings are not used (D21 Zig owns Ladybug CGO).
+// NOTE: never run `gofmt -w` on this file — it breaks the shebang.
+package main
+
+import (
+	"fmt"
+	"os"
+	"strings"
+
+	cliparse "github.com/eSlider/2dph/internal/cli"
+	"github.com/eSlider/2dph/internal/ocr"
+)
+
+func main() {
+	os.Exit(run(os.Args[1:]))
+}
+
+func run(args []string) int {
+	c, err := ocr.ParseArgs(args)
+	if err != nil {
+		return cliparse.Fail(err)
+	}
+	path := c.Path
+	var text string
+	if strings.HasSuffix(strings.ToLower(path), ".pdf") {
+		text, err = ocr.PDFFile(path)
+	} else {
+		text, err = ocr.ImageFile(path)
+	}
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "mail/ocr: %v\n", err)
+		return 1
+	}
+	fmt.Println(text)
+	return 0
+}

bin/mail/sync/cli.go

@@ -5,12 +5,15 @@ package sync
 
 import (
 	"context"
-	"flag"
+	"errors"
 	"fmt"
 	"os"
 	"path/filepath"
 	"strings"
 	"time"
+
+	cliparse "github.com/eSlider/2dph/internal/cli"
+	"github.com/integrii/flaggy"
 )
 
 // CLIConfig is a superset of SyncConfig plus flag parsing results.
@@ -21,58 +24,84 @@ type CLIConfig struct {
 	Help    bool
 }
 
-// ParseCLI reads os.Args into a CLIConfig. Exit codes: 0 ok, 2 usage.
+type flagVals struct {
+	env, out, srcs, query string
+	workers, limit, offset int
+	force, dryRun         bool
+}
+
+func Parser() *flaggy.Parser {
+	v := flagVals{workers: 4, query: "in:inbox", srcs: "onlyoffice"}
+	return bind(&v)
+}
+
+func bind(v *flagVals) *flaggy.Parser {
+	if v.workers == 0 {
+		v.workers = 4
+	}
+	if v.query == "" {
+		v.query = "in:inbox"
+	}
+	if v.srcs == "" {
+		v.srcs = "onlyoffice"
+	}
+	p := cliparse.New("mail-sync")
+	p.Description = "download mail to var/mail"
+	p.String(&v.env, "", "env", ".env file")
+	p.String(&v.out, "", "out", "var/mail root")
+	p.Int(&v.workers, "", "workers", "concurrent downloads")
+	p.Int(&v.limit, "", "limit", "max messages per source (0 = all)")
+	p.Int(&v.offset, "", "offset", "skip first N messages per source")
+	p.Bool(&v.force, "", "force", "overwrite existing message.json")
+	p.Bool(&v.dryRun, "", "dry-run", "list counts without writing")
+	p.String(&v.query, "", "query", "Gmail search query")
+	p.String(&v.srcs, "", "source", "comma list: onlyoffice,gmail")
+	return p
+}
+
+// ParseCLI reads args into a CLIConfig. Exit codes: 0 ok, 2 usage.
 func ParseCLI(args []string) (CLIConfig, int, error) {
-	fs := flag.NewFlagSet("mail/sync", flag.ContinueOnError)
+	v := flagVals{workers: 4, query: "in:inbox", srcs: "onlyoffice"}
-	var (
+	p := bind(&v)
-		env    = fs.String("env", "", ".env file (default: <cwd>/.env)")
+	if err := cliparse.Parse(p, args); err != nil {
-		out    = fs.String("out", "", "var/mail root (default: <cwd>/var/mail)")
+		if errors.Is(err, cliparse.ErrHelp) {
-		workers = fs.Int("workers", 4, "concurrent downloads")
+			return CLIConfig{Help: true}, 0, nil
-		limit  = fs.Int("limit", 0, "max messages per source (0 = all)")
+		}
-		offset = fs.Int("offset", 0, "skip first N messages per source")
-		force  = fs.Bool("force", false, "overwrite existing message.json + attachments")
-		dryRun = fs.Bool("dry-run", false, "list message counts without writing")
-		query  = fs.String("query", "in:inbox", "Gmail search query (gmail source only)")
-		srcs   = fs.String("source", "onlyoffice", "comma list: onlyoffice,gmail (default onlyoffice)")
-		help   = fs.Bool("help", false, "usage")
-	)
-	fs.SetOutput(os.Stderr)
-	if err := fs.Parse(args); err != nil {
 		return CLIConfig{}, 2, err
 	}
-	if *help || fs.NArg() > 0 {
+	if len(p.TrailingArguments) > 0 {
 		return CLIConfig{Help: true}, 0, nil
 	}
 	wd, err := os.Getwd()
 	if err != nil {
 		return CLIConfig{}, 2, err
 	}
-	if *env == "" {
+	if v.env == "" {
-		*env = filepath.Join(wd, ".env")
+		v.env = filepath.Join(wd, ".env")
 	}
-	if *out == "" {
+	if v.out == "" {
-		*out = filepath.Join(wd, "var", "mail")
+		v.out = filepath.Join(wd, "var", "mail")
 	}
-	envVars := readEnv(*env)
+	envVars := readEnv(v.env)
 	cfg := SyncConfig{
-		Out:     *out,
+		Out:     v.out,
-		Workers: *workers,
+		Workers: v.workers,
-		Limit:   *limit,
+		Limit:   v.limit,
-		Offset:  *offset,
+		Offset:  v.offset,
-		Force:   *force,
+		Force:   v.force,
-		DryRun:  *dryRun,
+		DryRun:  v.dryRun,
-		Query:   *query,
+		Query:   v.query,
 		Policy:  RetryPolicy{},
 	}
-	cli := CLIConfig{Sync: cfg, Env: *env, Sources: *srcs}
+	out := CLIConfig{Sync: cfg, Env: v.env, Sources: v.srcs}
-	for _, s := range strings.Split(*srcs, ",") {
+	for _, s := range strings.Split(v.srcs, ",") {
 		switch strings.TrimSpace(s) {
 		case "onlyoffice":
 			u := pick(envVars["ONLYOFFICE_URL"], envVars["OO_URL"])
 			user := pick(envVars["ONLYOFFICE_USER"], envVars["OO_USER"])
 			pass := pick(envVars["ONLYOFFICE_PASS"], envVars["OO_PASSWORD"])
 			if u == "" || user == "" || pass == "" {
-				return CLIConfig{}, 2, fmt.Errorf("onlyoffice source needs ONLYOFFICE_URL/USER/PASS in %s", *env)
+				return CLIConfig{}, 2, fmt.Errorf("onlyoffice source needs ONLYOFFICE_URL/USER/PASS in %s", v.env)
 			}
 			cfg.OO = &OOConfig{URL: u, User: user, Password: pass}
 		case "gmail":
@@ -85,30 +114,30 @@ func ParseCLI(args []string) (CLIConfig, int, error) {
 			return CLIConfig{}, 2, fmt.Errorf("unknown source %q", s)
 		}
 	}
-	cli.Sync = cfg
+	out.Sync = cfg
-	return cli, 0, nil
+	return out, 0, nil
 }
 
 // Main is the CLI entry: returns process exit code.
 func Main(args []string) int {
-	cli, code, err := ParseCLI(args)
+	cfg, code, err := ParseCLI(args)
 	if err != nil {
 		fmt.Fprintln(os.Stderr, "mail/sync:", err)
 		return code
 	}
-	if cli.Help {
+	if cfg.Help {
 		fmt.Fprintln(os.Stderr, "usage: bin/mail/sync.go [--source onlyoffice,gmail] [--query GMAIL_Q] [--limit N] [--offset N] [--workers N] [--force] [--dry-run]")
 		return 0
 	}
 	ctx, cancel := context.WithTimeout(context.Background(), 6*time.Hour)
 	defer cancel()
 	start := time.Now()
-	stats, err := Run(ctx, cli.Sync)
+	stats, err := Run(ctx, cfg.Sync)
 	if err != nil {
 		fmt.Fprintln(os.Stderr, "mail/sync:", err)
 		return 1
 	}
-	if cli.Sync.DryRun {
+	if cfg.Sync.DryRun {
 		fmt.Printf("mail/sync: dry-run checked=%d (no writes)\n", stats.Checked)
 		return 0
 	}
@@ -135,7 +164,6 @@ func readEnv(path string) map[string]string {
 		k, v, _ := strings.Cut(line, "=")
 		out[strings.TrimSpace(k)] = strings.Trim(strings.TrimSpace(v), "\"'")
 	}
-	// env overrides file
 	for _, kv := range os.Environ() {
 		k, v, ok := strings.Cut(kv, "=")
 		if !ok {

bin/markdown/import.go

@@ -1,20 +1,85 @@
-//usr/bin/env go run -tags=markdown_import "$0" "$@"; exit
+//usr/bin/env go run "$0" "$@"; exit
-//go:build markdown_import
 //
-// bin/markdown/import.go - split markdown into leafs (mistune).
+// bin/markdown/import.go - split markdown into leafs (H2 boundaries).
 //
 //	./bin/markdown/import.go [dir]
 //	./bin/markdown/import.go --files a.md,b.md --json
 //
+// Conversion only. Brain write is bin/brain/index.go.
+// Python bin/md/import remains as a fallback.
 // NOTE: never run `gofmt -w` on this file — it breaks the shebang.
 package main
 
 import (
+	"fmt"
 	"os"
+	"strings"
 
-	"github.com/eSlider/2dph/internal/cmdbin"
+	cliparse "github.com/eSlider/2dph/internal/cli"
+	"github.com/eSlider/2dph/internal/mdleaves"
 )
 
 func main() {
-	os.Exit(cmdbin.ExecFile("bin/md/import", os.Args[1:]))
+	os.Exit(run(os.Args[1:]))
+}
+
+func run(args []string) int {
+	c, err := mdleaves.ParseArgs(args)
+	if err != nil {
+		return cliparse.Fail(err)
+	}
+	jsonOut := c.JSONOut
+	files := c.Files
+	root := c.Root
+
+	var paths []string
+	if files != "" {
+		for _, f := range strings.Split(files, ",") {
+			f = strings.TrimSpace(f)
+			if f != "" {
+				paths = append(paths, f)
+			}
+		}
+	} else {
+		st, err := os.Stat(root)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "md/import: no such path %s\n", root)
+			return 2
+		}
+		if !st.IsDir() {
+			paths = []string{root}
+		} else {
+			var err error
+			paths, err = mdleaves.WalkMarkdown(root)
+			if err != nil {
+				fmt.Fprintf(os.Stderr, "md/import: %v\n", err)
+				return 1
+			}
+		}
+	}
+	if len(paths) == 0 {
+		fmt.Fprintln(os.Stderr, "md/import: no markdown files")
+		return 1
+	}
+
+	var all []mdleaves.Leaf
+	for _, p := range paths {
+		raw, err := os.ReadFile(p)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "md/import: %s: %v\n", p, err)
+			continue
+		}
+		all = append(all, mdleaves.ToAll(string(raw), p, "")...)
+	}
+	if jsonOut {
+		s, err := mdleaves.EncodeJSON(all)
+		if err != nil {
+			fmt.Fprintln(os.Stderr, err)
+			return 1
+		}
+		fmt.Print(s)
+		return 0
+	}
+	fmt.Print(mdleaves.EncodeYAML(all))
+	return 0
 }

bin/qa/stats.go

@@ -0,0 +1,61 @@
+//usr/bin/env go run -tags=qa_stats "$0" "$@"; exit
+//go:build qa_stats
+//
+// bin/qa/stats.go - DuckDB quantiles over a JSON number array or JSONL count.
+//
+//	./bin/qa/stats.go <<< '[1,2,3,4,5]'
+//	./bin/qa/stats.go --jsonl rows.jsonl
+//
+// NOTE: never run `gofmt -w` on this file — it breaks the shebang.
+// DuckDB CGO needs gcc/g++ (not Zig). After eval "$(bin/cgo/zig env)":
+//   CC=gcc CXX=g++ CGO_CFLAGS= CGO_LDFLAGS= ./bin/qa/stats.go
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"os"
+
+	cliparse "github.com/eSlider/2dph/internal/cli"
+	"github.com/eSlider/2dph/internal/duckstats"
+)
+
+func main() {
+	os.Exit(run(os.Args[1:]))
+}
+
+func run(args []string) int {
+	c, err := cliparse.ParseQAStats(args)
+	if err != nil {
+		return cliparse.Fail(err)
+	}
+	jsonl := c.JSONL
+	if jsonl != "" {
+		n, err := duckstats.CountJSONL(jsonl)
+		if err != nil {
+			fmt.Fprintln(os.Stderr, err)
+			return 1
+		}
+		fmt.Printf("n: %d\n", n)
+		return 0
+	}
+	raw, err := io.ReadAll(os.Stdin)
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		return 1
+	}
+	var samples []float64
+	if err := json.Unmarshal(raw, &samples); err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		return 1
+	}
+	s, err := duckstats.Quantiles(samples)
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		return 1
+	}
+	fmt.Printf("n: %d\nmin: %g\np50: %g\np95: %g\nmax: %g\navg: %g\n",
+		s.N, s.Min, s.P50, s.P95, s.Max, s.Avg)
+	return 0
+}

bin/reasoner/bakeoff.go

@@ -0,0 +1,73 @@
+//usr/bin/env go run -tags=reasoner_bakeoff "$0" "$@"; exit
+//go:build reasoner_bakeoff
+//
+// bin/reasoner/bakeoff.go - CPU tool-call bake-off against an OpenAI-compatible URL (D18).
+//
+//	REASONER_BASE_URL=http://127.0.0.1:11435/v1 REASONER_MODEL=qwen3.5:9b ./bin/reasoner/bakeoff.go
+//	./bin/reasoner/bakeoff.go --model MichelRosselli/bonsai-27b:Q1_0 --json
+//
+// Measures OpenAI tool_calls (search/get/audit) and RSS from Ollama /api/ps, not VRAM.
+// PicoClaw is compose profile picoclaw; tool names match internal/httpapi MCP ops.
+// NOTE: never run `gofmt -w` on this file — it breaks the shebang.
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+
+	cliparse "github.com/eSlider/2dph/internal/cli"
+	"github.com/eSlider/2dph/internal/duckstats"
+	"github.com/eSlider/2dph/internal/reasoner"
+)
+
+func main() {
+	os.Exit(run(os.Args[1:]))
+}
+
+func run(args []string) int {
+	c, err := reasoner.ParseArgs(args)
+	if err != nil {
+		return cliparse.Fail(err)
+	}
+	base, model, jsonOut, device := c.Base, c.Model, c.JSONOut, c.Device
+	client := reasoner.Client{BaseURL: base, Model: model, Device: device}
+	rep := reasoner.Run(client)
+	lat := make([]float64, 0, len(rep.Prompts))
+	for _, p := range rep.Prompts {
+		lat = append(lat, float64(p.LatencyMS))
+	}
+	if st, err := duckstats.Quantiles(lat); err == nil {
+		rep.LatencyP50MS = st.P50
+		rep.LatencyP95MS = st.P95
+	}
+	raw, err := json.MarshalIndent(rep, "", "  ")
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		return 1
+	}
+	if jsonOut {
+		fmt.Println(string(raw))
+	} else {
+		fmt.Printf("model: %s\n", rep.Model)
+		fmt.Printf("hf_id: %s\n", rep.HF)
+		fmt.Printf("device: %s\n", rep.Device)
+		fmt.Printf("tool_call: %d/%d\n", rep.ToolCallOK, rep.ToolCallN)
+		fmt.Printf("xml_leak: %d\n", rep.XMLLeak)
+		fmt.Printf("rss_mb: %d\n", rep.RSSMB)
+		fmt.Printf("vram_mb: %d\n", rep.VRAMMB)
+		fmt.Printf("latency_p50_ms: %g\n", rep.LatencyP50MS)
+		fmt.Printf("latency_p95_ms: %g\n", rep.LatencyP95MS)
+		for _, p := range rep.Prompts {
+			status := "fail"
+			if p.OK {
+				status = "ok"
+			}
+			fmt.Printf("  %s: %s wanted=%s got=%s xml=%v %dms %s\n", p.WantedTool, status, p.WantedTool, p.ToolName, p.XMLLeak, p.LatencyMS, p.Err)
+		}
+	}
+	if rep.ToolCallN == 0 {
+		return 1
+	}
+	return 0
+}

bin/reasoner/doc.go

@@ -0,0 +1,2 @@
+// Commands in this directory are shebang mains (bakeoff.go).
+package main

bin/stack/lib.sh

@@ -0,0 +1,235 @@
+# bin/stack/lib.sh — compose helpers for start / start-assistant / stop / status.
+# Sourced, not executed. No secrets. No host-absolute paths.
+
+BRAIN_URL="${BRAIN_URL:-http://127.0.0.1:8630}"
+REASONER_URL="${REASONER_URL:-http://127.0.0.1:11435}"
+PICOCLAW_URL="${PICOCLAW_URL:-http://127.0.0.1:18790}"
+REASONER_MODEL="${REASONER_MODEL:-qwen3.5:9b}"
+STACK_WAIT_SECS="${STACK_WAIT_SECS:-90}"
+STACK_WAIT_INTERVAL="${STACK_WAIT_INTERVAL:-2}"
+STACK_PULL_SECS="${STACK_PULL_SECS:-600}"
+
+if [[ -z "${ROOT:-}" ]]; then
+	STACK_DIR="$(CDPATH= cd -- "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+	ROOT="$(CDPATH= cd -- "$STACK_DIR/../.." && pwd)"
+fi
+
+stack_usage() {
+	awk 'NR == 1 { next } /^#/ { sub(/^# ?/, ""); print; next } { exit }' "$1"
+}
+
+stack_die() {
+	echo "bin/stack: $*" >&2
+	return 1
+}
+
+compose() {
+	docker compose -f "$ROOT/compose.yaml" --project-directory "$ROOT" "$@"
+}
+
+http_get() {
+	local url=$1
+	local timeout=${2:-5}
+	curl -sS --max-time "$timeout" "$url" 2>/dev/null || return 1
+}
+
+health_ok() {
+	local url=$1
+	local timeout=${2:-5}
+	local body
+	body=$(http_get "$url" "$timeout") || return 1
+	printf '%s' "$body" | grep -q '"status":"ok"'
+}
+
+wait_health() {
+	local url=$1
+	local n=0
+	while ((n <= STACK_WAIT_SECS)); do
+		if health_ok "$url"; then
+			return 0
+		fi
+		n=$((n + 1))
+		if ((n <= STACK_WAIT_SECS)); then
+			sleep "$STACK_WAIT_INTERVAL"
+		fi
+	done
+	return 1
+}
+
+wait_http() {
+	local url=$1
+	local n=0
+	while ((n <= STACK_WAIT_SECS)); do
+		if http_get "$url" 5 >/dev/null; then
+			return 0
+		fi
+		n=$((n + 1))
+		if ((n <= STACK_WAIT_SECS)); then
+			sleep "$STACK_WAIT_INTERVAL"
+		fi
+	done
+	return 1
+}
+
+mcp_body() {
+	curl -sS --max-time 10 \
+		-H 'Content-Type: application/json' \
+		-d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}' \
+		"$BRAIN_URL/mcp" 2>/dev/null || return 1
+}
+
+mcp_ok() {
+	local body
+	body=$(mcp_body) || return 1
+	printf '%s' "$body" | grep -Eq '"name": ?"search"' || return 1
+	printf '%s' "$body" | grep -Eq '"name": ?"get"' || return 1
+	printf '%s' "$body" | grep -Eq '"name": ?"audit"' || return 1
+	return 0
+}
+
+reasoner_tags() {
+	http_get "$REASONER_URL/api/tags" 5
+}
+
+reasoner_has_model() {
+	local body
+	body=$(reasoner_tags) || return 1
+	printf '%s' "$body" | grep -Fq "$REASONER_MODEL"
+}
+
+ensure_mcp() {
+	mcp_ok || stack_die "MCP tools/list missing search/get/audit at $BRAIN_URL/mcp"
+}
+
+ensure_brain() {
+	if health_ok "$BRAIN_URL/health"; then
+		echo "brain: reuse $BRAIN_URL" >&2
+	else
+		echo "brain: compose up" >&2
+		compose up -d brain
+		wait_health "$BRAIN_URL/health" || stack_die "brain health failed at $BRAIN_URL/health"
+	fi
+	ensure_mcp
+}
+
+pull_reasoner_model() {
+	echo "reasoner: pulling $REASONER_MODEL (CPU, may take minutes)" >&2
+	curl -sS --max-time "$STACK_PULL_SECS" \
+		-H 'Content-Type: application/json' \
+		-d "{\"name\":\"$REASONER_MODEL\"}" \
+		"$REASONER_URL/api/pull" >/dev/null
+}
+
+ensure_reasoner() {
+	if reasoner_has_model; then
+		echo "reasoner: reuse $REASONER_URL model $REASONER_MODEL" >&2
+		return 0
+	fi
+	if ! reasoner_tags >/dev/null; then
+		echo "reasoner: compose up" >&2
+		compose --profile reasoner up -d reasoner
+		wait_http "$REASONER_URL/api/tags" || stack_die "reasoner not listening at $REASONER_URL"
+	fi
+	if reasoner_has_model; then
+		return 0
+	fi
+	pull_reasoner_model
+	reasoner_has_model || stack_die "reasoner missing model $REASONER_MODEL"
+}
+
+ensure_picoclaw() {
+	echo "picoclaw: compose up --no-deps (reuse healthy :8630/:11435)" >&2
+	compose --profile picoclaw up -d --no-deps picoclaw
+	wait_health "$PICOCLAW_URL/health" || stack_die "picoclaw health failed at $PICOCLAW_URL/health"
+}
+
+stack_status() {
+	local bh=down mcp=down ph=down present=false
+	health_ok "$BRAIN_URL/health" && bh=ok
+	mcp_ok && mcp=ok
+	reasoner_has_model && present=true
+	health_ok "$PICOCLAW_URL/health" && ph=ok
+	cat <<EOF
+brain:
+  url: $BRAIN_URL
+  health: $bh
+  mcp: $mcp
+reasoner:
+  url: $REASONER_URL
+  model: $REASONER_MODEL
+  present: $present
+picoclaw:
+  url: $PICOCLAW_URL
+  health: $ph
+EOF
+}
+
+stack_start() {
+	ensure_brain
+}
+
+stack_attach_agent() {
+	local opts=()
+	if [[ -t 0 && -t 1 ]]; then
+		opts+=(-it)
+	else
+		opts+=(-T)
+	fi
+	if [[ (! -t 0 || ! -t 1) && $# -eq 0 ]]; then
+		echo "picoclaw: no TTY. Attach with:" >&2
+		echo "  $ROOT/bin/stack/start-assistant" >&2
+		echo "  docker compose --profile picoclaw exec -it picoclaw picoclaw agent" >&2
+		return 0
+	fi
+	echo "picoclaw: agent (search → get → audit before a factual reply)" >&2
+	exec docker compose -f "$ROOT/compose.yaml" --project-directory "$ROOT" \
+		--profile picoclaw exec "${opts[@]}" picoclaw picoclaw agent "$@"
+}
+
+stack_start_assistant() {
+	local attach=1
+	local agent_args=()
+	while (($#)); do
+		case "$1" in
+		-h | --help)
+			stack_usage "$ROOT/bin/stack/start-assistant"
+			return 0
+			;;
+		--no-attach)
+			attach=0
+			shift
+			;;
+		--)
+			shift
+			agent_args+=("$@")
+			break
+			;;
+		*)
+			agent_args+=("$1")
+			shift
+			;;
+		esac
+	done
+	stack_start
+	ensure_reasoner
+	ensure_picoclaw
+	stack_status
+	if ((attach == 0)); then
+		echo "picoclaw: gateway $PICOCLAW_URL (agent not attached)" >&2
+		echo "ask the brain: $ROOT/bin/stack/start-assistant" >&2
+		echo "one-shot: $ROOT/bin/stack/start-assistant -- -m \"search the 2dph brain for LadybugDB\"" >&2
+		return 0
+	fi
+	stack_attach_agent "${agent_args[@]}"
+}
+
+stack_stop() {
+	case "${1:-}" in
+	-h | --help)
+		stack_usage "$ROOT/bin/stack/stop"
+		return 0
+		;;
+	esac
+	echo "stack: stop brain brain-mcp reasoner picoclaw (volumes kept)" >&2
+	compose --profile picoclaw --profile reasoner stop picoclaw brain-mcp reasoner brain
+}

bin/stack/start

@@ -0,0 +1,21 @@
+#!/usr/bin/env bash
+# bin/stack/start - bring up brain HTTP/MCP and wait until search/get/audit respond.
+#
+#   bin/stack/start
+#   bin/stack/status
+#
+# Reuses a healthy process on :8630 (host serve or compose). Does not start
+# PicoClaw. Does not rebuild Ladybug.
+set -euo pipefail
+
+STACK_DIR="$(CDPATH= cd -- "$(dirname "$0")" && pwd)"
+# shellcheck source=lib.sh
+source "$STACK_DIR/lib.sh"
+case "${1:-}" in
+-h | --help)
+	stack_usage "$0"
+	exit 0
+	;;
+esac
+stack_start "$@"
+stack_status

bin/stack/start-assistant

@@ -0,0 +1,15 @@
+#!/usr/bin/env bash
+# bin/stack/start-assistant - start + CPU reasoner + PicoClaw, then attach agent.
+#
+#   bin/stack/start-assistant
+#   bin/stack/start-assistant --no-attach
+#   bin/stack/start-assistant -- -m "search the 2dph brain for LadybugDB"
+#
+# Pulls qwen3.5:9b if missing. Gateway :18790. Agent uses MCP search → get → audit.
+# --no-attach leaves the gateway up without exec.
+set -euo pipefail
+
+STACK_DIR="$(CDPATH= cd -- "$(dirname "$0")" && pwd)"
+# shellcheck source=lib.sh
+source "$STACK_DIR/lib.sh"
+stack_start_assistant "$@"

bin/stack/status

@@ -0,0 +1,17 @@
+#!/usr/bin/env bash
+# bin/stack/status - YAML health for brain MCP, reasoner model, PicoClaw gateway.
+#
+#   bin/stack/status
+#   bin/stack/status | yq '.picoclaw'
+set -euo pipefail
+
+STACK_DIR="$(CDPATH= cd -- "$(dirname "$0")" && pwd)"
+# shellcheck source=lib.sh
+source "$STACK_DIR/lib.sh"
+case "${1:-}" in
+-h | --help)
+	stack_usage "$0"
+	exit 0
+	;;
+esac
+stack_status

bin/stack/stop

@@ -0,0 +1,13 @@
+#!/usr/bin/env bash
+# bin/stack/stop - stop compose brain / brain-mcp / reasoner / picoclaw.
+#
+#   bin/stack/stop
+#
+# Volumes kept (kb, reasoner weights, picoclaw-home). Does not kill a host
+# bin/brain/serve.go that is not a compose service.
+set -euo pipefail
+
+STACK_DIR="$(CDPATH= cd -- "$(dirname "$0")" && pwd)"
+# shellcheck source=lib.sh
+source "$STACK_DIR/lib.sh"
+stack_stop "$@"

bin/tools/contradict.py

@@ -0,0 +1,103 @@
+"""D16 contradiction adjudication (same rules as internal/facts)."""
+from __future__ import annotations
+
+from typing import Any
+
+CONF_CONFIRMED = "confirmed"
+CONF_HYPOTHESIS = "hypothesis"
+
+RULE_UNRESOLVED = "unresolved"
+RULE_TEMPORAL = "temporal_freshness"
+RULE_AUTHORITY = "authority_pairing"
+RULE_TWO_SOURCE = "two_source"
+RULE_SINGLE = "single_source"
+
+KIND_RUNTIME = "runtime"
+KIND_CONFIG = "config"
+KIND_NARRATIVE = "narrative"
+
+
+def _independent(sources: list[dict]) -> int:
+    seen: set[str] = set()
+    for i, s in enumerate(sources):
+        sid = str(s.get("id") or "") or f"{s.get('kind', '')}#{i}"
+        seen.add(sid)
+    return len(seen)
+
+
+def _fresh_n(sources: list[dict]) -> int:
+    return sum(1 for s in sources if not s.get("stale"))
+
+
+def _strong_n(sources: list[dict]) -> int:
+    return sum(1 for s in sources if s.get("kind") in (KIND_RUNTIME, KIND_CONFIG))
+
+
+def adjudicate(claim: dict[str, Any]) -> dict[str, Any]:
+    yes = list(claim.get("yes") or [])
+    no = list(claim.get("no") or [])
+    yes_n, no_n = _independent(yes), _independent(no)
+    text = str(claim.get("text") or "")
+
+    def out(conf: str, rule: str, winner: str = "") -> dict[str, Any]:
+        return {
+            "text": text,
+            "confidence": conf,
+            "confirmed": conf == CONF_CONFIRMED,
+            "rule": rule,
+            "winner": winner,
+            "yes": yes_n,
+            "no": no_n,
+        }
+
+    if yes_n < 2 or no_n < 2:
+        if yes_n >= 2:
+            return out(CONF_CONFIRMED, RULE_TWO_SOURCE, "yes")
+        if no_n >= 2:
+            return out(CONF_CONFIRMED, RULE_TWO_SOURCE, "no")
+        return out(CONF_HYPOTHESIS, RULE_SINGLE)
+    yf, nf = _fresh_n(yes), _fresh_n(no)
+    if yf >= 2 and nf < 2:
+        return out(CONF_CONFIRMED, RULE_TEMPORAL, "yes")
+    if nf >= 2 and yf < 2:
+        return out(CONF_CONFIRMED, RULE_TEMPORAL, "no")
+    ys, ns = _strong_n(yes), _strong_n(no)
+    if ys >= 2 and ns < 2:
+        return out(CONF_CONFIRMED, RULE_AUTHORITY, "yes")
+    if ns >= 2 and ys < 2:
+        return out(CONF_CONFIRMED, RULE_AUTHORITY, "no")
+    return out(CONF_HYPOTHESIS, RULE_UNRESOLVED)
+
+
+def parse_source_field(source: str) -> tuple[str, str]:
+    """Split `a x b vs c x d` into (yes, no). Empty no if no ` vs `."""
+    if " vs " not in source:
+        return source, ""
+    yes, _, no = source.partition(" vs ")
+    return yes.strip(), no.strip()
+
+
+def check_fact_row(lid: str, source: str, loc: str, how: str, conf: str) -> list[str]:
+    """Lexicon checks for one facts leaf (no Ladybug)."""
+    problems: list[str] = []
+    src = source or ""
+    if conf == CONF_CONFIRMED:
+        if " vs " in src:
+            problems.append(f"{lid}: confirmed fact cannot keep a vs-contradiction")
+        if " x " not in src:
+            problems.append(f"{lid}: needs 2-source evidence in source, got '{source}'")
+    elif conf == CONF_HYPOTHESIS:
+        yes, no = parse_source_field(src)
+        if not no or " x " not in yes or " x " not in no:
+            problems.append(
+                f"{lid}: hypothesis contradiction needs 'a x b vs c x d', got '{source}'"
+            )
+    elif conf == "partial":
+        pass
+    else:
+        problems.append(f"{lid}: unknown confidence '{conf}'")
+    if not loc:
+        problems.append(f"{lid}: missing loc (evidence pointer)")
+    if not how:
+        problems.append(f"{lid}: missing how")
+    return problems

bin/tools/kblib.py

@@ -4,7 +4,7 @@ Single embedded graph `var/kb.lbug`. Two roots: facts (assertions backed by
 >=2 independent sources) and info (narrative leafs). Hybrid retrieval: BM25
 (FTS extension) + HNSW cosine (VECTOR extension) + Cypher graph hops.
 
-All access is read-only unless `--rebuild` is passed to kb/index.
+All access is read-only unless `--rebuild` (kb/index) or `kb/add`.
 """
 from __future__ import annotations
 
@@ -62,7 +62,9 @@ def init_schema(conn: ladybug.Connection) -> None:
         "CREATE NODE TABLE IF NOT EXISTS Leaf ("
         " id STRING, text STRING, root STRING, confidence STRING, "
         " sha256 STRING, source STRING, source_rev STRING, observed_at STRING, "
-        " how STRING, loc STRING, type STRING, embedding FLOAT[256], "
+        " how STRING, loc STRING, type STRING, "
+        " valid_from STRING, valid_to STRING, "
+        " embedding FLOAT[256], "
         " PRIMARY KEY(id))"
     )
     conn.execute(
@@ -91,6 +93,46 @@ def init_schema(conn: ladybug.Connection) -> None:
     conn.execute(
         "CREATE REL TABLE IF NOT EXISTS AUTHORED (FROM Commit TO Person)"
     )
+    ensure_interval_columns(conn)
+
+
+def ensure_interval_columns(conn: ladybug.Connection) -> None:
+    """D24: add valid_from/valid_to on older Leaf tables (idempotent ALTER)."""
+    for col in ("valid_from", "valid_to"):
+        try:
+            conn.execute(f"ALTER TABLE Leaf ADD {col} STRING")
+        except Exception:
+            pass
+
+
+def normalize_day(s: str) -> str:
+    s = (s or "").strip()
+    if len(s) >= 10 and s[4] == "-" and s[7] == "-":
+        return s[:10]
+    return s
+
+
+def active_at(valid_from: str, valid_to: str, as_of: str) -> bool:
+    """D24: fact interval of truth. Empty ends = always; empty as_of = no filter."""
+    as_of = normalize_day(as_of)
+    if not as_of:
+        return True
+    fro = normalize_day(valid_from)
+    to = normalize_day(valid_to)
+    if fro and as_of < fro:
+        return False
+    if to and as_of > to:
+        return False
+    return True
+
+
+def filter_as_of(hits: list[dict], as_of: str) -> list[dict]:
+    if not as_of:
+        return hits
+    return [
+        h for h in hits
+        if active_at(str(h.get("valid_from") or ""), str(h.get("valid_to") or ""), as_of)
+    ]
 
 
 def leaf_id(text: str, source: str) -> str:
@@ -99,25 +141,124 @@ def leaf_id(text: str, source: str) -> str:
 
 def upsert_leaf(conn: ladybug.Connection, *, text: str, root: str, confidence: str,
                 source: str, source_rev: str, how: str, loc: str, type_: str,
-                embedding: list[float] | None) -> str:
+                embedding: list[float] | None,
+                valid_from: str = "", valid_to: str = "") -> str:
     lid = leaf_id(text, source)
     obs = time.strftime("%Y-%m-%dT%H:%M:%SZ", time.gmtime())
+    vf = normalize_day(valid_from)
+    vt = normalize_day(valid_to)
     conn.execute(
         "MERGE (l:Leaf {id:$id}) "
         "SET l.text=$text, l.root=$root, l.confidence=$confidence, "
         "    l.sha256=$sha, l.source=$source, l.source_rev=$rev, l.observed_at=$obs, "
-        "    l.how=$how, l.loc=$location, l.type=$type"
+        "    l.how=$how, l.loc=$location, l.type=$type, "
+        "    l.valid_from=$vf, l.valid_to=$vt"
         + (", l.embedding=$emb" if embedding else ""),
         parameters={
             "id": lid, "text": text, "root": root, "confidence": confidence,
             "sha": sha256_b64(text), "source": source, "rev": source_rev,
             "obs": obs, "how": how, "location": loc, "type": type_,
+            "vf": vf, "vt": vt,
             "emb": (embedding if embedding else None),
         },
     )
     return lid
 
 
+def add_leafs(conn: ladybug.Connection, leafs: list[dict]) -> list[str]:
+    """Write facts+info leafs in one transaction. Safe while FTS/HNSW exist.
+
+    Each leaf dict: text, source, optional root/confidence/source_rev/how/loc/type/
+    embedding/valid_from/valid_to. Does not delete the database file. Measured on
+    Ladybug 0.19: MERGE of new ids (and updates) stays FTS+HNSW queryable; DROP
+    INDEX is the fatal path.
+    """
+    if not leafs:
+        return []
+    started = False
+    try:
+        conn.execute("BEGIN TRANSACTION")
+        started = True
+    except Exception:
+        started = False
+    ids: list[str] = []
+    try:
+        for lf in leafs:
+            ids.append(
+                upsert_leaf(
+                    conn,
+                    text=str(lf["text"]),
+                    root=str(lf.get("root") or ROOT_INFO),
+                    confidence=str(lf.get("confidence") or CONF_CONFIRMED),
+                    source=str(lf["source"]),
+                    source_rev=str(lf.get("source_rev") or "working-tree"),
+                    how=str(lf.get("how") or "brain/add"),
+                    loc=str(lf.get("loc") or lf.get("source") or ""),
+                    type_=str(lf.get("type") or lf.get("type_") or "reference"),
+                    embedding=lf.get("embedding"),
+                    valid_from=str(lf.get("valid_from") or ""),
+                    valid_to=str(lf.get("valid_to") or ""),
+                )
+            )
+        if started:
+            conn.execute("COMMIT")
+    except Exception:
+        if started:
+            try:
+                conn.execute("ROLLBACK")
+            except Exception:
+                pass
+        raise
+    return ids
+
+
+def file_id(repo: str, path: str) -> str:
+    """Stable File.id matching gitimport (`repo:path`)."""
+    return f"{repo}:{path}" if repo else path
+
+
+def link_from_file(conn: ladybug.Connection, leaf_id: str, path: str,
+                   repo: str = "", mtime: str = "") -> str:
+    """MERGE File and Leaf-[:FROM_FILE]->File so --hop 1 can walk."""
+    fid = file_id(repo, path)
+    conn.execute(
+        "MERGE (f:File {id:$id}) SET f.path=$path, f.repo=$repo, f.mtime=$mtime",
+        parameters={"id": fid, "path": path, "repo": repo, "mtime": mtime},
+    )
+    conn.execute(
+        "MATCH (l:Leaf {id:$lid}), (f:File {id:$fid}) "
+        "MERGE (l)-[:FROM_FILE]->(f)",
+        parameters={"lid": leaf_id, "fid": fid},
+    )
+    return fid
+
+
+HOP_STMTS = {
+    1: "MATCH (l:Leaf {id:$id})-[:FROM_FILE]->(f:File) RETURN f.id, f.path, 1",
+    2: ("MATCH (l:Leaf {id:$id})-[:FROM_FILE]->(f:File)-[:HAS_VERSION]->(c:Commit) "
+        "RETURN c.id, c.subject, 2"),
+    3: ("MATCH (l:Leaf {id:$id})-[:FROM_FILE]->(f:File)-[:HAS_VERSION]->(c:Commit)"
+        "-[:AUTHORED]->(p:Person) RETURN p.id, p.name, 3"),
+}
+HOP_LABELS = {1: "File", 2: "Commit", 3: "Person"}
+
+
+def hop_walk(conn: ladybug.Connection, leaf_id: str, n: int) -> list[dict]:
+    """Walk Leaf → File → Commit → Person up to n hops (max 3)."""
+    depth = min(max(int(n), 0), 3)
+    out: list[dict] = []
+    for d in range(1, depth + 1):
+        rows = conn.execute(HOP_STMTS[d], parameters={"id": leaf_id}).get_all()
+        for row in rows:
+            out.append({
+                "id": row[0],
+                "label": HOP_LABELS[d],
+                "name": row[1],
+                "depth": int(row[2]),
+            })
+    return out
+
+
 def leaf_index_names(conn: ladybug.Connection) -> set[str]:
     """Return index names on the Leaf table (e.g. {'id', 'Leaf_vec', '_PK'})."""
     rows = conn.execute("CALL SHOW_INDEXES() RETURN *").get_all()
@@ -194,29 +335,39 @@ def drop_indexes(conn: ladybug.Connection) -> None:
 def query_fts(conn: ladybug.Connection, text: str, limit: int = 10) -> list[dict]:
     r = conn.execute(
         "CALL QUERY_FTS_INDEX('Leaf', 'id', $q) "
-        "RETURN node.id, node.text, node.root, score ORDER BY score DESC LIMIT $n",
+        "RETURN node.id, node.text, node.root, score, node.valid_from, node.valid_to "
+        "ORDER BY score DESC LIMIT $n",
         parameters={"q": text, "n": limit},
     )
-    return [{"id": row[0], "text": row[1], "root": row[2], "score": row[3]} for row in r.get_all()]
+    return [
+        {
+            "id": row[0], "text": row[1], "root": row[2], "score": row[3],
+            "valid_from": row[4] or "", "valid_to": row[5] or "",
+        }
+        for row in r.get_all()
+    ]
 
 
 def query_vector(conn: ladybug.Connection, embedding: list[float], limit: int = 10) -> list[dict]:
     r = conn.execute(
         "CALL QUERY_VECTOR_INDEX('Leaf', 'Leaf_vec', $q, $n) "
-        "RETURN node.id, node.text, node.root, distance ORDER BY distance LIMIT $n",
+        "RETURN node.id, node.text, node.root, distance, node.valid_from, node.valid_to "
+        "ORDER BY distance LIMIT $n",
         parameters={"q": embedding, "n": limit},
     )
     out = []
     for row in r.get_all():
-        # distance -> similarity reasonable for cosine
         score = 1.0 - row[3] if row[3] is not None else 0.0
-        out.append({"id": row[0], "text": row[1], "root": row[2], "score": score})
+        out.append({
+            "id": row[0], "text": row[1], "root": row[2], "score": score,
+            "valid_from": row[4] or "", "valid_to": row[5] or "",
+        })
     return out
 
 
 def hybrid_search(conn: ladybug.Connection, embedding: list[float], fts_hits: list[dict],
-                  limit: int = 10) -> list[dict]:
+                  limit: int = 10, as_of: str = "") -> list[dict]:
-    """Merge FTS + vector by reciprocal rank fusion."""
+    """Merge FTS + vector by reciprocal rank fusion; optional D24 as-of filter."""
     fused: dict[str, dict] = {}
     for rank, hit in enumerate(fts_hits):
         fused.setdefault(hit["id"], {**hit, "rrf": 0.0})["rrf"] = 1.0 / (60 + rank + 1)
@@ -224,8 +375,10 @@ def hybrid_search(conn: ladybug.Connection, embedding: list[float], fts_hits: li
         entry = fused.setdefault(hit["id"], {**hit, "rrf": 0.0})
         entry["rrf"] += 1.0 / (60 + rank + 1)
         entry.setdefault("score", hit.get("score", 0.0))
+        entry.setdefault("valid_from", hit.get("valid_from") or "")
+        entry.setdefault("valid_to", hit.get("valid_to") or "")
     ranked = sorted(fused.values(), key=lambda h: h.get("rrf", 0.0), reverse=True)
-    return ranked[:limit]
+    return filter_as_of(ranked, as_of)[:limit]
 
 
 def stats(conn: ladybug.Connection) -> dict:

bin/tools/mailconv.py

@@ -7,7 +7,10 @@ offline against fixtures.
 from __future__ import annotations
 
 import html
+import os
 import re
+import subprocess
+import tempfile
 import zipfile
 from pathlib import Path
 
@@ -18,9 +21,10 @@ OFFICE_SUFFIXES = {".docx", ".pptx", ".xlsx", ".html", ".htm", ".epub", ".eml",
 PDF_SUFFIXES = {".pdf"}
 IMAGE_SUFFIXES = {".png", ".jpg", ".jpeg", ".gif", ".bmp", ".tiff", ".tif", ".webp"}
 ARCHIVE_SUFFIXES = {".zip"}
-# Legacy binary Office (doc/xls/ppt) — markitdown/docling skip them; we try
+# Legacy binary Office (doc/xls/ppt) — markitdown skip them; we try
 # pandoc first, else leave a stub.
 LEGACY_OFFICE_SUFFIXES = {".doc", ".xls", ".ppt"}
+TESS_LANG = "eng+deu"
 
 CONVERTIBLE_SUFFIXES = (
     TEXT_SUFFIXES | OFFICE_SUFFIXES | PDF_SUFFIXES | IMAGE_SUFFIXES | ARCHIVE_SUFFIXES | LEGACY_OFFICE_SUFFIXES
@@ -146,3 +150,82 @@ def zip_extract_safe(zip_path: Path, dest: Path) -> list[Path]:
 
 def is_convertible(suffix: str) -> bool:
     return suffix.lower() in CONVERTIBLE_SUFFIXES
+
+
+def convert_pdf(path: Path, ocr: bool = False) -> str:
+    """pdftotext -layout first; empty text layer → pdftoppm + tesseract.
+
+    `ocr` is unused for born-digital PDFs (text layer wins). Scans OCR
+    automatically. This path never execs an ONNX document converter.
+    """
+    del ocr  # scans OCR when the text layer is empty; flag is for images
+    text = pdf_fast_text(path)
+    if text and text.strip():
+        return normalize_markdown(text)
+    scanned = ocr_pdf(path)
+    if scanned and scanned.strip():
+        return normalize_markdown(scanned)
+    if text:
+        return normalize_markdown(text)
+    return "\n<!-- pdf has no text layer (ocr unavailable) -->\n"
+
+
+def pdf_fast_text(path: Path) -> str | None:
+    """pdftotext -layout; None when poppler is missing or the command fails."""
+    try:
+        proc = subprocess.run(
+            ["pdftotext", "-layout", str(path), "-"],
+            capture_output=True, timeout=60)
+    except (OSError, subprocess.TimeoutExpired):
+        return None
+    if proc.returncode != 0:
+        return None
+    return proc.stdout.decode("utf-8", errors="replace")
+
+
+def ocr_pdf(path: Path) -> str:
+    """Rasterize with pdftoppm and OCR each page (tesseract or paddle)."""
+    try:
+        with tempfile.TemporaryDirectory(prefix="2dph-ocr-") as tmp:
+            prefix = str(Path(tmp) / "page")
+            proc = subprocess.run(
+                ["pdftoppm", "-png", "-r", "200", str(path), prefix],
+                capture_output=True, timeout=120)
+            if proc.returncode != 0:
+                return ""
+            pages = sorted(Path(tmp).glob("page*.png"))
+            parts = [ocr_image(p) for p in pages]
+            return "\n\n".join(p for p in parts if p and p.strip())
+    except (OSError, subprocess.TimeoutExpired):
+        return ""
+
+
+def ocr_image(path: Path) -> str:
+    engine = os.environ.get("OCR_ENGINE", "tesseract")
+    if engine == "paddle":
+        return _ocr_paddle(path)
+    return _ocr_tesseract(path)
+
+
+def _ocr_tesseract(path: Path) -> str:
+    try:
+        proc = subprocess.run(
+            ["tesseract", str(path), "stdout", "-l", TESS_LANG, "--psm", "6"],
+            capture_output=True, timeout=120)
+    except (OSError, subprocess.TimeoutExpired):
+        return ""
+    if proc.returncode != 0:
+        return ""
+    return proc.stdout.decode("utf-8", errors="replace").strip()
+
+
+def _ocr_paddle(path: Path) -> str:
+    try:
+        proc = subprocess.run(
+            ["paddleocr", "ocr", "-i", str(path)],
+            capture_output=True, timeout=180)
+    except (OSError, subprocess.TimeoutExpired):
+        return ""
+    if proc.returncode != 0:
+        return ""
+    return proc.stdout.decode("utf-8", errors="replace").strip()

bin/tools/test_bin_layout.py

@@ -1,6 +1,7 @@
 """D14 layout: bin/{subject}/{method}.go, libs in internal/, one go.mod."""
 from __future__ import annotations
 
+import os
 import unittest
 from pathlib import Path
 
@@ -74,9 +75,20 @@ class BinLayoutTest(unittest.TestCase):
         )
 
     def test_brain_methods_are_shebangs(self) -> None:
-        for method in ("index.go", "get.go", "stats.go", "eval.go", "watch.go"):
+        for method in ("index.go", "add.go", "get.go", "stats.go", "eval.go", "watch.go"):
             self._assert_shebang(f"bin/brain/{method}")
 
+    def test_brain_add_is_python_write_not_rebuild(self) -> None:
+        self._assert_shebang("bin/brain/add.go")
+        text = (ROOT / "bin" / "brain" / "add.go").read_text()
+        self.assertIn("cmdbin.ExecFile", text)
+        self.assertIn("bin/kb/add", text)
+        self.assertNotIn("--rebuild", text)
+        py = (ROOT / "bin" / "kb" / "add").read_text()
+        self.assertIn("add_leafs", py)
+        self.assertIn("--json", py)
+        self.assertNotIn("unlink", py.lower())
+
     def test_brain_get_stats_eval_are_not_python_exec(self) -> None:
         for method in ("get.go", "stats.go", "eval.go"):
             text = (ROOT / "bin" / "brain" / method).read_text()
@@ -115,6 +127,38 @@ class BinLayoutTest(unittest.TestCase):
             self.assertIn("cmdbin.ExecFile", text)
             self.assertIn(f"bin/facts/{method.removesuffix('.go')}", text)
 
+    def test_d16_adjudication_is_cgo_free(self) -> None:
+        self.assertTrue((ROOT / "internal" / "facts" / "contradict.go").is_file())
+        go = (ROOT / "internal" / "facts" / "contradict.go").read_text()
+        py = (ROOT / "bin" / "tools" / "contradict.py").read_text()
+        audit = (ROOT / "bin" / "facts" / "audit").read_text()
+        for token in ("temporal_freshness", "authority_pairing", "unresolved"):
+            self.assertIn(token, go)
+            self.assertIn(token, py)
+        self.assertIn("contradict", audit)
+        self.assertIn(" vs ", py)
+        plan = (ROOT / "PLAN.md").read_text()
+        self.assertIn("temporal_freshness", plan)
+        self.assertIn("authority_pairing", plan)
+        shebang = (ROOT / "bin" / "facts" / "audit.go").read_text()
+        self.assertIn("contradict", shebang)
+
+    def test_d23_flaggy_cli(self) -> None:
+        self.assertTrue((ROOT / "internal" / "cli" / "cli.go").is_file())
+        self.assertIn("github.com/integrii/flaggy", (ROOT / "go.mod").read_text())
+        plan = (ROOT / "PLAN.md").read_text()
+        self.assertIn("D23", plan)
+        self.assertIn("flaggy", plan)
+        complete = (ROOT / "bin" / "cli" / "complete.go").read_text()
+        first = complete.splitlines()[0]
+        self.assertTrue(first.startswith("//usr/bin/env go run"), first)
+        self.assertIn("complete.go bash", complete)
+        self.assertIn("brain-search", complete)
+        chats_import = (ROOT / "internal" / "chats" / "import.go").read_text()
+        self.assertNotIn("flag.NewFlagSet", chats_import)
+        args = (ROOT / "internal" / "brain" / "rank" / "args.go").read_text()
+        self.assertIn("internal/cli", args)
+
     def test_mail_import_is_shebang_not_brain_write(self) -> None:
         self._assert_shebang("bin/mail/import.go")
         index_mail = (ROOT / "bin" / "mail" / "index_mail").read_text()
@@ -124,8 +168,55 @@ class BinLayoutTest(unittest.TestCase):
             "index_mail must point at bin/brain/index.go",
         )
 
-    def test_markdown_import_is_shebang(self) -> None:
+    def test_mail_ocr_is_tesseract_not_docling(self) -> None:
+        self._assert_shebang("bin/mail/ocr.go")
+        ocr = (ROOT / "bin" / "mail" / "ocr.go").read_text()
+        self.assertIn("internal/ocr", ocr)
+        self.assertIn("mail_ocr", ocr)
+        self.assertNotIn("github.com/otiai10/gosseract", ocr)
+        py = (ROOT / "bin" / "mail" / "import").read_text()
+        self.assertNotIn("from docling", py)
+        self.assertNotIn("import docling", py)
+        self.assertIn("convert_pdf", py)
+        conv = (ROOT / "bin" / "tools" / "mailconv.py").read_text()
+        self.assertIn("pdftotext", conv)
+        self.assertIn("pdftoppm", conv)
+        self.assertIn("tesseract", conv)
+        self.assertIn("eng+deu", conv)
+        self.assertNotIn("from docling", conv)
+        self.assertNotIn("import docling", conv)
+        self.assertNotIn("gocv", conv.lower())
+        proj = (ROOT / "pyproject.toml").read_text()
+        self.assertNotIn("docling", proj)
+        ci = (ROOT / ".github" / "workflows" / "ci.yml").read_text()
+        self.assertIn("tesseract-ocr", ci)
+        self.assertIn("./internal/ocr", ci)
+        compose = (ROOT / "compose.yaml").read_text()
+        self.assertIn("ocr-paddle", compose)
+        self.assertIn("OCR_ENGINE", compose)
+
+    def test_markdown_import_is_go_not_python_exec(self) -> None:
         self._assert_shebang("bin/markdown/import.go")
+        text = (ROOT / "bin" / "markdown" / "import.go").read_text()
+        self.assertNotIn("ExecFile", text)
+        self.assertNotIn("cmdbin", text)
+        self.assertIn("internal/mdleaves", text)
+        self.assertNotIn("kb.lbug", text)
+
+    def test_import_adapters_do_not_write_ladybug(self) -> None:
+        for rel in (
+            "bin/mail/import.go",
+            "bin/mail/import",
+            "bin/markdown/import.go",
+            "bin/chats/import.go",
+            "bin/git/import.go",
+        ):
+            text = (ROOT / rel).read_text()
+            self.assertNotIn("upsert_leaf", text, rel)
+            self.assertNotIn("kb.lbug", text, rel)
+            self.assertNotIn("var/brain.lbug", text, rel)
+        index = (ROOT / "bin" / "brain" / "index.go").read_text()
+        self.assertIn("bin/kb/index", index)
 
     def test_postgres_query_is_shebang(self) -> None:
         self._assert_shebang("bin/postgres/query.go")
@@ -157,3 +248,69 @@ class BinLayoutTest(unittest.TestCase):
         for line in first.splitlines():
             if "go-git/go-git" in line:
                 self.assertNotIn("indirect", line)
+
+    def test_duckdb_go_is_direct_require(self) -> None:
+        text = (ROOT / "go.mod").read_text()
+        first = text.split("require (")[1].split(")")[0]
+        self.assertRegex(first, r"github.com/duckdb/duckdb-go/v2\s+v")
+        for line in first.splitlines():
+            if "duckdb/duckdb-go" in line:
+                self.assertNotIn("indirect", line)
+        skill = (ROOT / "skills" / "duckdb" / "SKILL.md").read_text()
+        self.assertIn("github.com/duckdb/duckdb-go", skill)
+        self.assertIn("Ladybug", skill)
+        self.assertIn("sqlite", skill.lower())
+        self.assertIn("gcc", skill.lower())
+        self.assertIn("Zig", skill)
+        plan = (ROOT / "PLAN.md").read_text()
+        self.assertIn("D22", plan)
+        self.assertIn("duckdb-go", plan)
+        self._assert_shebang("bin/qa/stats.go")
+        reasoner = (ROOT / "internal" / "reasoner" / "client.go").read_text()
+        self.assertNotIn("duckdb", reasoner)
+        self.assertNotIn("duckstats", reasoner)
+        bakeoff = (ROOT / "bin" / "reasoner" / "bakeoff.go").read_text()
+        self.assertIn("internal/duckstats", bakeoff)
+        webcache = (ROOT / "internal" / "websearch" / "cache.go").read_text()
+        self.assertNotIn("duckdb", webcache)
+        self.assertIn("modernc.org/sqlite", webcache)
+
+    def test_cgo_uses_zig_not_gcc(self) -> None:
+        for rel in ("bin/cgo/zig", "bin/cgo/zcc", "bin/cgo/zc++"):
+            p = ROOT / rel
+            self.assertTrue(p.is_file(), f"missing {rel}")
+            self.assertTrue(
+                os.access(p, os.X_OK),
+                f"{rel} must be executable",
+            )
+        zig = (ROOT / "bin" / "cgo" / "zig").read_text()
+        self.assertIn("zig cc", zig)
+        self.assertIn("0.14.1", zig)
+        zcc = (ROOT / "bin" / "cgo" / "zcc").read_text()
+        self.assertIn('exec "$ZIG" cc', zcc)
+        self.assertNotIn("command -v gcc", zcc)
+        search = (ROOT / "bin" / "kb" / "search").read_text()
+        self.assertIn("bin/cgo/zig", search)
+        self.assertNotIn("command -v gcc", search)
+
+    def test_ci_recall_sot_is_zig_brain_eval(self) -> None:
+        ci = (ROOT / ".github" / "workflows" / "ci.yml").read_text()
+        self.assertIn("bin/brain/eval.go", ci)
+        self.assertIn("system_ladybug,brain_eval", ci)
+        self.assertIn("/tmp/brain-eval", ci)
+        self.assertIn("KB_ROOT", ci)
+        self.assertNotIn("bin/kb/eval", ci)
+        self.assertNotIn("gate skipped", ci)
+        self.assertIn("./bin/facts/audit self", ci)
+
+    def test_eval_fragments_live_in_default_corpus(self) -> None:
+        """CI --rebuild indexes README/PLAN/docs/skills; fragments must be there."""
+        corpus = []
+        for rel in ("README.md", "PLAN.md", "AGENTS.md"):
+            corpus.append((ROOT / rel).read_text())
+        for d in ("docs", "skills"):
+            for p in (ROOT / d).rglob("*.md"):
+                corpus.append(p.read_text())
+        blob = "\n".join(corpus)
+        for frag in ("BM25", "DevOps", "LadybugDB"):
+            self.assertIn(frag, blob, f"{frag} must appear in default index corpus")

bin/tools/test_contradict.py

@@ -0,0 +1,104 @@
+import os
+import sys
+import unittest
+
+sys.path.insert(0, os.path.dirname(__file__))
+
+from contradict import (  # noqa: E402
+    RULE_AUTHORITY,
+    RULE_SINGLE,
+    RULE_TEMPORAL,
+    RULE_TWO_SOURCE,
+    RULE_UNRESOLVED,
+    adjudicate,
+    check_fact_row,
+    parse_source_field,
+)
+
+
+def src(i, kind, stale=False):
+    return {"id": i, "kind": kind, "stale": stale}
+
+
+class TestContradict(unittest.TestCase):
+    def test_two_vs_two_stays_hypothesis(self):
+        r = adjudicate({
+            "text": "svc listens on 443",
+            "yes": [src("docker-ps", "runtime"), src("compose", "config")],
+            "no": [src("docker-old", "runtime"), src("compose-old", "config")],
+        })
+        self.assertFalse(r["confirmed"])
+        self.assertEqual(r["rule"], RULE_UNRESOLVED)
+        self.assertEqual(r["winner"], "")
+
+    def test_temporal_freshness(self):
+        r = adjudicate({
+            "text": "svc listens on 443",
+            "yes": [src("docker-ps", "runtime"), src("compose", "config")],
+            "no": [src("old-readme", "narrative", True), src("old-wiki", "narrative", True)],
+        })
+        self.assertTrue(r["confirmed"])
+        self.assertEqual(r["rule"], RULE_TEMPORAL)
+        self.assertEqual(r["winner"], "yes")
+
+    def test_authority_pairing(self):
+        r = adjudicate({
+            "text": "svc listens on 443",
+            "yes": [src("docker-ps", "runtime"), src("compose", "config")],
+            "no": [src("readme", "narrative"), src("wiki", "narrative")],
+        })
+        self.assertTrue(r["confirmed"])
+        self.assertEqual(r["rule"], RULE_AUTHORITY)
+        self.assertEqual(r["winner"], "yes")
+
+    def test_two_source_and_single(self):
+        two = adjudicate({
+            "text": "arc-1 runs Matrix",
+            "yes": [src("compose", "config"), src("docker-ps", "runtime")],
+        })
+        self.assertTrue(two["confirmed"])
+        self.assertEqual(two["rule"], RULE_TWO_SOURCE)
+        one = adjudicate({"text": "maybe", "yes": [src("readme", "narrative")]})
+        self.assertFalse(one["confirmed"])
+        self.assertEqual(one["rule"], RULE_SINGLE)
+
+    def test_parse_source_field(self):
+        yes, no = parse_source_field("docker ps x compose.yml vs old.md x wiki.md")
+        self.assertIn(" x ", yes)
+        self.assertIn(" x ", no)
+
+    def test_check_fact_row_allows_hypothesis_vs(self):
+        p = check_fact_row(
+            "L1", "a.md x b.md vs c.md x d.md", "var/", "audit", "hypothesis",
+        )
+        self.assertEqual(p, [])
+        p = check_fact_row("L2", "a.md x b.md", "var/", "audit", "confirmed")
+        self.assertEqual(p, [])
+        p = check_fact_row("L3", "a.md x b.md vs c.md x d.md", "var/", "audit", "confirmed")
+        self.assertTrue(any("vs-contradiction" in x for x in p))
+        p = check_fact_row("L4", "only-one.md", "var/", "audit", "hypothesis")
+        self.assertTrue(any("a x b vs" in x for x in p))
+
+    def test_audit_contradict_cli_unresolved(self):
+        import json
+        import subprocess
+        from pathlib import Path
+        root = Path(__file__).resolve().parents[2]
+        payload = json.dumps({
+            "text": "svc 443",
+            "yes": [src("a", "runtime"), src("b", "config")],
+            "no": [src("c", "runtime"), src("d", "config")],
+        })
+        proc = subprocess.run(
+            [sys.executable, str(root / "bin" / "facts" / "audit"), "contradict", "--json"],
+            input=payload, capture_output=True, text=True, check=False,
+        )
+        self.assertEqual(proc.returncode, 0, proc.stderr)
+        out = json.loads(proc.stdout)
+        self.assertTrue(out["ok"])
+        self.assertEqual(out["contradictions"][0]["rule"], RULE_UNRESOLVED)
+        self.assertFalse(out["contradictions"][0]["confirmed"])
+
+
+if __name__ == "__main__":
+    unittest.main()

bin/tools/test_index_adapters.py

@@ -0,0 +1,97 @@
+"""Import adapters write files only. Index rebuild is brain/index (D14 / Gitea #7)."""
+from __future__ import annotations
+
+import json
+import os
+import subprocess
+import sys
+import tempfile
+import unittest
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parents[2]
+
+
+class IndexAdapterTest(unittest.TestCase):
+    def test_dry_run_fixture_corpus_does_not_write_lbug(self) -> None:
+        tmp = Path(tempfile.mkdtemp())
+        (tmp / "note.md").write_text("# Fixture\n\n## Leaf\n\nhello corpus\n", encoding="utf-8")
+        lbug = tmp / "kb.lbug"
+        try:
+            import ladybug  # noqa: F401
+        except ImportError:
+            venv_py = ROOT / ".venv" / "bin" / "python"
+            if not venv_py.is_file():
+                self.skipTest("ladybug missing")
+            py = str(venv_py)
+        else:
+            py = sys.executable
+        proc = subprocess.run(
+            [py, str(ROOT / "bin" / "kb" / "index"), "--dry-run", "--json", "--corpus", str(tmp)],
+            cwd=ROOT,
+            capture_output=True,
+            text=True,
+            env=os.environ.copy(),
+            check=False,
+        )
+        self.assertEqual(proc.returncode, 0, proc.stderr)
+        msg = json.loads(proc.stdout)
+        self.assertTrue(msg.get("dry_run"))
+        self.assertGreaterEqual(msg.get("corpus_total", 0), 1)
+        self.assertFalse(lbug.exists(), "dry-run must not create a Ladybug file")
+
+    def test_facts_json_and_chats_land_on_rebuild(self) -> None:
+        """Gitea #18: facts (2-source) + chats markdown become leafs on rebuild."""
+        tmp = Path(tempfile.mkdtemp())
+        dbpath = tmp / "kb.lbug"
+        chats = tmp / "chats"
+        chats.mkdir()
+        (chats / "alice.md").write_text(
+            "# Chat\n\n## Alice and Bob\n\nhello from chats fixture unique-chat-token\n",
+            encoding="utf-8",
+        )
+        facts_path = tmp / "facts.json"
+        facts_path.write_text(json.dumps([{
+            "text": "container 'brain' unique-fact-token is running and declared in compose.yaml",
+            "source": "docker ps x compose.yaml",
+            "loc": "compose.yaml:brain",
+            "how": "facts/extract",
+        }]), encoding="utf-8")
+        venv_py = ROOT / ".venv" / "bin" / "python"
+        py = str(venv_py) if venv_py.is_file() else sys.executable
+        proc = subprocess.run(
+            [
+                py, str(ROOT / "bin" / "kb" / "index"),
+                "--rebuild", "--db", str(dbpath), "--no-defaults",
+                "--with-chats", str(chats),
+                "--facts-json", str(facts_path),
+                "--json",
+            ],
+            cwd=ROOT,
+            capture_output=True,
+            text=True,
+            env=os.environ.copy(),
+            check=False,
+        )
+        self.assertEqual(proc.returncode, 0, proc.stderr)
+        msg = json.loads(proc.stdout)
+        self.assertGreaterEqual(msg.get("facts_leafs", 0), 1)
+        self.assertGreaterEqual(msg.get("chat_leafs", 0), 1)
+        self.assertTrue(dbpath.exists())
+        sys.path.insert(0, str(ROOT / "bin" / "tools"))
+        import kblib
+        db, conn = kblib.connect(dbpath, read_only=True)
+        try:
+            stats = kblib.stats(conn)
+            self.assertGreaterEqual(stats["by_root"].get("facts", 0), 1)
+            fts = kblib.query_fts(conn, "unique-chat-token", 5)
+            self.assertTrue(fts, "chats markdown must be FTS-searchable")
+            fact_hits = kblib.query_fts(conn, "unique-fact-token", 5)
+            self.assertTrue(any(h.get("root") == "facts" for h in fact_hits))
+            src = conn.execute(
+                "MATCH (l:Leaf {root:'facts'}) RETURN l.source"
+            ).get_all()
+            self.assertTrue(any(" x " in str(r[0]) for r in src))
+        finally:
+            conn.close()
+            db.close()

bin/tools/test_kb_add.py

@@ -0,0 +1,69 @@
+"""Incremental add writes leafs without deleting kb.lbug."""
+from __future__ import annotations
+
+import json
+import os
+import subprocess
+import sys
+import tempfile
+import unittest
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parents[2]
+
+
+class KbAddCLITest(unittest.TestCase):
+    def test_json_add_does_not_delete_db(self) -> None:
+        tmp = Path(tempfile.mkdtemp())
+        dbpath = tmp / "kb.lbug"
+        py = sys.executable
+        venv_py = ROOT / ".venv" / "bin" / "python"
+        if venv_py.is_file():
+            py = str(venv_py)
+        payload = {
+            "text": "cli zebra leaf",
+            "root": "info",
+            "source": "cli-test",
+            "confidence": "confirmed",
+            "how": "test",
+            "loc": str(tmp),
+            "type": "reference",
+            "embedding": [0.0] * 256,
+        }
+        payload["embedding"][0] = 0.3
+        proc = subprocess.run(
+            [py, str(ROOT / "bin" / "kb" / "add"), "--db", str(dbpath), "--json"],
+            cwd=ROOT,
+            input=json.dumps(payload),
+            capture_output=True,
+            text=True,
+            env=os.environ.copy(),
+            check=False,
+        )
+        self.assertEqual(proc.returncode, 0, proc.stderr)
+        self.assertTrue(dbpath.exists(), "add must create the db, not skip write")
+        out = json.loads(proc.stdout)
+        self.assertEqual(out.get("mode"), "add")
+        self.assertEqual(len(out.get("ids") or []), 1)
+        again = subprocess.run(
+            [py, str(ROOT / "bin" / "kb" / "add"), "--db", str(dbpath), "--json"],
+            cwd=ROOT,
+            input=json.dumps({
+                **payload,
+                "text": "second moose leaf",
+                "source": "cli-test-2",
+            }),
+            capture_output=True,
+            text=True,
+            env=os.environ.copy(),
+            check=False,
+        )
+        self.assertEqual(again.returncode, 0, again.stderr)
+        self.assertTrue(dbpath.exists())
+        second = json.loads(again.stdout)
+        self.assertEqual(len(second.get("ids") or []), 1)
+        self.assertNotEqual(out["ids"][0], second["ids"][0])
+
+
+if __name__ == "__main__":
+    unittest.main()

bin/tools/test_kblib.py

@@ -71,6 +71,69 @@ class KblibTest(unittest.TestCase):
         self.assertTrue(hits)
         self.assertIn("Leaf_vec", kblib.leaf_index_names(self.conn))
 
+    def test_add_after_indexes_keeps_fts_queryable(self):
+        """Incremental add after FTS+HNSW must find the new leaf on both indexes."""
+        kblib.upsert_leaf(self.conn, text="seed fox leaf", root="info",
+                          confidence="confirmed", source="s", source_rev="r1",
+                          how="test", loc="/tmp", type_="reference",
+                          embedding=make_emb(0.1))
+        kblib.ensure_indexes(self.conn)
+        ids = kblib.add_leafs(self.conn, [{
+            "text": "added zebra after index",
+            "root": "facts",
+            "confidence": "confirmed",
+            "source": "a.md x b.md",
+            "source_rev": "r1",
+            "how": "test",
+            "loc": "/tmp",
+            "type": "fact",
+            "embedding": make_emb(0.9),
+        }])
+        self.assertEqual(len(ids), 1)
+        fts = kblib.query_fts(self.conn, "zebra", 5)
+        self.assertTrue(fts)
+        self.assertIn("zebra", fts[0]["text"])
+        self.assertEqual(fts[0]["root"], "facts")
+        vec = kblib.query_vector(self.conn, make_emb(0.9), 5)
+        self.assertTrue(any("zebra" in h["text"] for h in vec))
+        fox = kblib.query_fts(self.conn, "fox", 5)
+        self.assertTrue(fox)
+        self.assertIn("fox", fox[0]["text"])
+
+    def test_add_facts_and_info_one_transaction(self):
+        """D12: facts and info land in the same transaction."""
+        kblib.ensure_indexes(self.conn)
+        ids = kblib.add_leafs(self.conn, [
+            {
+                "text": "tx fact leaf two-source",
+                "root": "facts",
+                "confidence": "confirmed",
+                "source": "compose.yml x docker ps",
+                "source_rev": "r1",
+                "how": "test",
+                "loc": "/tmp",
+                "type": "fact",
+                "embedding": make_emb(0.4),
+            },
+            {
+                "text": "tx info narrative",
+                "root": "info",
+                "confidence": "confirmed",
+                "source": "note.md",
+                "source_rev": "r1",
+                "how": "test",
+                "loc": "/tmp",
+                "type": "reference",
+                "embedding": make_emb(0.5),
+            },
+        ])
+        self.assertEqual(len(ids), 2)
+        stats = kblib.stats(self.conn)
+        self.assertEqual(stats["by_root"].get("facts"), 1)
+        self.assertEqual(stats["by_root"].get("info"), 1)
+        self.assertTrue(kblib.query_fts(self.conn, "two-source", 5))
+        self.assertTrue(kblib.query_fts(self.conn, "narrative", 5))
+
     def test_drop_vector_then_create_raises_clear_error(self):
         """DROP INDEX leaves ghost catalog; create_fts_and_vector must raise."""
         kblib.upsert_leaf(self.conn, text="seed", root="info",
@@ -98,6 +161,71 @@ class KblibTest(unittest.TestCase):
         self.assertEqual(stats["total"], 2)
         self.assertEqual(stats["by_root"], {"facts": 1, "info": 1})
 
+    def test_hop_1_returns_file_hop_3_reaches_person(self):
+        """--hop walks FROM_FILE / HAS_VERSION / AUTHORED (Gitea #17)."""
+        import gitimport
+
+        lid = kblib.upsert_leaf(
+            self.conn, text="readme hop fixture", root="info",
+            confidence="confirmed", source="README.md", source_rev="r1",
+            how="test", loc="README.md", type_="reference",
+            embedding=make_emb(0.3),
+        )
+        kblib.link_from_file(self.conn, lid, "README.md", repo="sample-repo")
+        gitimport.index_commits(self.conn, [gitimport.Commit(
+            sha="a1b2c3d",
+            author="Ada Lovelace",
+            email="ada@example.com",
+            date="2026-08-10T12:00:00Z",
+            subject="feat: first commit",
+            files=["README.md"],
+        )], "sample-repo")
+        hop1 = kblib.hop_walk(self.conn, lid, 1)
+        self.assertEqual(len(hop1), 1)
+        self.assertEqual(hop1[0]["label"], "File")
+        self.assertEqual(hop1[0]["name"], "README.md")
+        self.assertEqual(hop1[0]["depth"], 1)
+        hop3 = kblib.hop_walk(self.conn, lid, 3)
+        labels = {n["label"] for n in hop3}
+        self.assertIn("File", labels)
+        self.assertIn("Commit", labels)
+        self.assertIn("Person", labels)
+        person = [n for n in hop3 if n["label"] == "Person"][0]
+        self.assertEqual(person["name"], "Ada Lovelace")
+        self.assertEqual(person["depth"], 3)
+
+    def test_as_of_keeps_x_drops_y(self) -> None:
+        """OQ5/#36: as of 2025-01-01 → works-at-X, not works-at-Y."""
+        kblib.upsert_leaf(
+            self.conn, text="Andrey works at X", root="facts",
+            confidence="confirmed", source="crm.md x contract.md",
+            source_rev="r1", how="test", loc="/tmp", type_="fact",
+            embedding=make_emb(0.5),
+            valid_from="2024-03-01", valid_to="2025-07-15",
+        )
+        kblib.upsert_leaf(
+            self.conn, text="Andrey works at Y", root="facts",
+            confidence="confirmed", source="offer.md x payroll.md",
+            source_rev="r1", how="test", loc="/tmp", type_="fact",
+            embedding=make_emb(0.6),
+            valid_from="2025-07-16", valid_to="",
+        )
+        kblib.ensure_indexes(self.conn)
+        hits = kblib.query_fts(self.conn, "Andrey works", 10)
+        kept = kblib.filter_as_of(hits, "2025-01-01")
+        texts = [h["text"] for h in kept]
+        self.assertTrue(any("works at X" in t for t in texts), texts)
+        self.assertFalse(any("works at Y" in t for t in texts), texts)
+        later = kblib.filter_as_of(hits, "2025-08-01")
+        later_texts = [h["text"] for h in later]
+        self.assertTrue(any("works at Y" in t for t in later_texts), later_texts)
+        self.assertFalse(any("works at X" in t for t in later_texts), later_texts)
+
+    def test_active_at_pure(self) -> None:
+        self.assertTrue(kblib.active_at("2024-03-01", "2025-07-15", "2025-01-01"))
+        self.assertFalse(kblib.active_at("2025-07-16", "", "2025-01-01"))
+        self.assertTrue(kblib.active_at("", "", "2025-01-01"))
+
 
 if __name__ == "__main__":
     unittest.main()

bin/tools/test_mailconv.py

@@ -8,10 +8,13 @@ from pathlib import Path
 sys.path.insert(0, os.path.dirname(__file__))
 
 from mailconv import (  # noqa: E402
+    TESS_LANG,
     clean_email_address,
+    convert_pdf,
     html_to_markdown,
     is_convertible,
     normalize_markdown,
+    ocr_image,
     split_zip_members,
     subject_to_filename,
     zip_extract_safe,
@@ -100,6 +103,92 @@ class TestMailConv(unittest.TestCase):
         self.assertFalse(is_convertible(".exe"))
         self.assertFalse(is_convertible(".unknown"))
 
+    def test_convert_pdf_prefers_pdftotext(self):
+        import mailconv as mc
+
+        calls: list[list[str]] = []
+
+        def fake_run(cmd, **kwargs):
+            calls.append(list(cmd))
+
+            class P:
+                returncode = 0
+                stdout = b"Invoice BM25 layout"
+                stderr = b""
+
+            return P()
+
+        self._patch_run(mc, fake_run)
+        out = convert_pdf(Path(self._tmp("born.pdf")))
+        self.assertIn("BM25", out)
+        self.assertEqual(calls[0][:2], ["pdftotext", "-layout"])
+        self.assertFalse(any(c[0] == "tesseract" for c in calls))
+        self.assertFalse(any(c[0] == "pdftoppm" for c in calls))
+
+    def test_convert_pdf_empty_layer_uses_pdftoppm_tesseract(self):
+        import mailconv as mc
+
+        calls: list[list[str]] = []
+
+        def fake_run(cmd, **kwargs):
+            calls.append(list(cmd))
+
+            class P:
+                returncode = 0
+                stdout = b""
+                stderr = b""
+
+            if cmd[0] == "pdftotext":
+                P.stdout = b"  \n"
+                return P()
+            if cmd[0] == "pdftoppm":
+                prefix = Path(cmd[-1])
+                (prefix.parent / "page-1.png").write_bytes(b"fake")
+                return P()
+            if cmd[0] == "tesseract":
+                P.stdout = b"scanned HELLO"
+                return P()
+            return P()
+
+        self._patch_run(mc, fake_run)
+        out = convert_pdf(Path(self._tmp("scan.pdf")))
+        self.assertIn("HELLO", out)
+        bins = [c[0] for c in calls]
+        self.assertIn("pdftotext", bins)
+        self.assertIn("pdftoppm", bins)
+        self.assertIn("tesseract", bins)
+        tess = next(c for c in calls if c[0] == "tesseract")
+        self.assertIn(TESS_LANG, tess)
+        self.assertNotIn("docling", " ".join(bins))
+
+    def test_ocr_image_paddle_engine(self):
+        import mailconv as mc
+
+        calls: list[list[str]] = []
+
+        def fake_run(cmd, **kwargs):
+            calls.append(list(cmd))
+
+            class P:
+                returncode = 0
+                stdout = b"paddle text"
+                stderr = b""
+
+            return P()
+
+        self._patch_run(mc, fake_run)
+        os.environ["OCR_ENGINE"] = "paddle"
+        try:
+            out = ocr_image(Path(self._tmp("x.png")))
+        finally:
+            os.environ.pop("OCR_ENGINE", None)
+        self.assertEqual(out, "paddle text")
+        self.assertEqual(calls[0][:2], ["paddleocr", "ocr"])
+
+    def _patch_run(self, mod, fn) -> None:
+        self.addCleanup(setattr, mod.subprocess, "run", mod.subprocess.run)
+        mod.subprocess.run = fn
+
     def _mk_zip(self, members):
         zpath = Path(self._tmp("arc.zip"))
         with zipfile.ZipFile(zpath, "w") as zf:

bin/tools/test_published_docs.py

@@ -1,7 +1,6 @@
-"""Published docs must match live commands (Gitea SoT, brain/search, no fake --hop)."""
+"""Published docs must match live commands (Gitea SoT, brain/search)."""
 from __future__ import annotations
 
-import re
 import unittest
 from pathlib import Path
 
@@ -89,6 +88,49 @@ class PublishedDocsTest(unittest.TestCase):
         self.assertFalse((ROOT / "skills" / "db-yaml").exists())
         self.assertTrue((ROOT / "skills" / "postgres" / "SKILL.md").is_file())
 
+    def test_cgo_zig_and_index_profile(self) -> None:
+        plan = (ROOT / "PLAN.md").read_text()
+        self.assertIn("D21", plan)
+        self.assertIn("zig cc", plan)
+        dockerfile = (ROOT / "Dockerfile").read_text()
+        self.assertIn("bin/cgo/zcc", dockerfile)
+        self.assertIn("FROM debian:bookworm-slim AS api", dockerfile)
+        self.assertIn("FROM python:3.12-slim AS index", dockerfile)
+        api = dockerfile[dockerfile.index("FROM debian:bookworm-slim AS api") :]
+        self.assertNotIn("pip install", api)
+        compose = (ROOT / "compose.yaml").read_text()
+        self.assertIn('profiles: ["index"]', compose)
+        self.assertIn("target: api", compose)
+
+    def test_reasoner_docs_name_real_hf_ids_cpu_sidecar(self) -> None:
+        docs = (ROOT / "docs" / "reasoner.md").read_text()
+        for hf in (
+            "Qwen/Qwen3.5-9B",
+            "Qwen/Qwen3.6-27B",
+            "prism-ml/Bonsai-27B-gguf",
+        ):
+            self.assertIn(hf, docs)
+        self.assertIn("no official qwen3.6-9b", docs.lower())
+        self.assertIn("OLLAMA_NUM_GPU", docs)
+        self.assertIn("rss_mb", docs)
+        self.assertIn("vram_mb", docs)
+        self.assertIn("3/3", docs)
+        self.assertIn("Do not claim 9B is better at tools", docs)
+        self.assertNotIn("Qwen/Qwen3.6-9B", docs)
+        plan = (ROOT / "PLAN.md").read_text()
+        self.assertIn("D18", plan)
+        self.assertIn("Qwen/Qwen3.5-9B", plan)
+        compose = (ROOT / "compose.yaml").read_text()
+        self.assertIn('"reasoner"', compose)
+        self.assertIn("OLLAMA_NUM_GPU", compose)
+        self.assertIn("127.0.0.1:11435", compose)
+        dockerfile = (ROOT / "Dockerfile").read_text()
+        self.assertNotIn(".gguf", dockerfile.lower())
+        self.assertNotIn(".safetensors", dockerfile.lower())
+        api = dockerfile[dockerfile.index("FROM debian:bookworm-slim AS api") :]
+        self.assertNotIn("COPY models", api)
+        self.assertNotIn("qwen", api.lower())
+
     def test_readme_search_escalates_web(self) -> None:
         text = (ROOT / "README.md").read_text()
         self.assertIn("--no-web", text)
@@ -96,19 +138,69 @@ class PublishedDocsTest(unittest.TestCase):
         skill = (ROOT / "skills" / "brain" / "SKILL.md").read_text()
         self.assertIn("`web` block", skill)
 
-    def test_docs_do_not_claim_hop_walks(self) -> None:
+    def test_docs_say_hop_walks_from_file(self) -> None:
         paths = [
             ROOT / "README.md",
             ROOT / "docs" / "design.md",
             ROOT / "skills" / "brain" / "SKILL.md",
-            ROOT / "skills" / "diataxis-docs" / "SKILL.md",
+            ROOT / "docs" / "runbook.md",
+            ROOT / "docs" / "README.md",
         ]
-        # Command-style `--hop 1` / `--hop N` plus follow/walk = the old lie.
-        # Honest "not implemented" notes must not match.
-        lie = re.compile(r"--hop (?:N|1).*(?:follow|walk)", re.I | re.S)
         for path in paths:
             text = path.read_text()
-            self.assertIsNone(
+            self.assertIn("--hop", text, f"{path.relative_to(ROOT)} must document --hop")
-                lie.search(text),
+            self.assertNotIn(
-                f"{path.relative_to(ROOT)} still claims --hop walks the graph",
+                "not implemented",
+                text.lower(),
+                f"{path.relative_to(ROOT)} still says hop is not implemented",
             )
+
+    def test_docs_are_portable_diataxis(self) -> None:
+        index = (ROOT / "docs" / "README.md").read_text()
+        self.assertIn("type: reference", index)
+        for d in ("D3", "D6", "D14", "D15", "D17", "D18"):
+            self.assertIn(d, index)
+        runbook = (ROOT / "docs" / "runbook.md").read_text()
+        self.assertIn("type: howto", runbook)
+        self.assertIn("bin/brain/search.go", runbook)
+        self.assertIn("bin/brain/index.go", runbook)
+        self.assertNotIn("search.ops.io", runbook)
+        self.assertNotIn("/mnt/", runbook)
+        self.assertNotIn("/home/", runbook)
+        readme = (ROOT / "README.md").read_text()
+        self.assertIn("docs/runbook.md", readme)
+        self.assertNotIn("search.ops.io", readme)
+
+    def test_v1_epic_is_named_in_docs(self) -> None:
+        plan = (ROOT / "PLAN.md").read_text()
+        self.assertIn("Gap to v1", plan)
+        self.assertIn("eSlider/2dph/issues/16", plan)
+        self.assertIn("eSlider/2dph/issues/17", plan)
+        self.assertIn("eSlider/2dph/milestone/12", plan)
+        road = (ROOT / "docs" / "roadmap.md").read_text()
+        self.assertIn("type: explanation", road)
+        self.assertIn("issues/16", road)
+        self.assertIn("issues/14", road)
+        index = (ROOT / "docs" / "README.md").read_text()
+        self.assertIn("roadmap.md", index)
+        self.assertIn("epic #16", index)
+        agents = (ROOT / "AGENTS.md").read_text()
+        self.assertIn("roadmap.md", agents)
+
+    def test_oq5_intervals_are_not_d16_stale(self) -> None:
+        plan = (ROOT / "PLAN.md").read_text()
+        design = (ROOT / "docs" / "design.md").read_text()
+        road = (ROOT / "docs" / "roadmap.md").read_text()
+        contradict = (ROOT / "internal" / "facts" / "contradict.go").read_text()
+        interval = (ROOT / "internal" / "facts" / "interval.go").read_text()
+        self.assertIn("OQ5", plan)
+        self.assertIn("D24", plan)
+        self.assertIn("issues/36", plan)
+        self.assertIn("valid_from", plan)
+        self.assertIn("--as-of", design)
+        self.assertIn("issues/36", road)
+        self.assertIn("**in**", road[road.index("OQ5"):road.index("OQ5") + 80])
+        self.assertIn("temporal_freshness", contradict)
+        self.assertNotIn("valid_from", contradict)
+        self.assertIn("ActiveAt", interval)
+        self.assertIn("NormalizeDay", interval)

bin/tools/test_skills.py

@@ -47,3 +47,17 @@ class SkillsTest(unittest.TestCase):
         self.assertIn("throttled", skill.lower())
         self.assertIn("not a negative finding", agents)
         self.assertIn("Fact-check every", agents)
+
+    def test_yq_is_mikefarah_for_structured_data(self) -> None:
+        skill = (ROOT / "skills" / "yq" / "SKILL.md").read_text()
+        self.assertIn("https://github.com/mikefarah/yq", skill)
+        for fmt in ("YAML", "JSON", "XML", "CSV", "TOML", "HCL"):
+            self.assertIn(fmt, skill)
+        self.assertIn("not kislyuk", skill.lower())
+        plan = (ROOT / "PLAN.md").read_text()
+        self.assertIn("mikefarah/yq", plan)
+        agents = (ROOT / "AGENTS.md").read_text()
+        self.assertIn("mikefarah/yq", agents)
+        web = (ROOT / "skills" / "web-search" / "SKILL.md").read_text()
+        self.assertIn("| yq ", web)
+        self.assertNotIn("| jq ", web)

bin/tools/test_stack.py

@@ -0,0 +1,213 @@
+"""bin/stack/{start,start-assistant,stop,status} — offline contract + fake PATH."""
+from __future__ import annotations
+
+import os
+import stat
+import subprocess
+import tempfile
+import unittest
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parents[2]
+METHODS = ("start", "start-assistant", "stop", "status")
+
+
+class StackLayoutTest(unittest.TestCase):
+    def test_methods_are_bash_with_usage_comment(self) -> None:
+        lib = ROOT / "bin" / "stack" / "lib.sh"
+        self.assertTrue(lib.is_file(), "missing bin/stack/lib.sh")
+        for name in METHODS:
+            p = ROOT / "bin" / "stack" / name
+            self.assertTrue(p.is_file(), f"missing bin/stack/{name}")
+            self.assertTrue(os.access(p, os.X_OK), f"bin/stack/{name} must be executable")
+            lines = p.read_text().splitlines()
+            self.assertEqual(lines[0], "#!/usr/bin/env bash", name)
+            self.assertTrue(lines[1].startswith("# bin/stack/"), name)
+            text = "\n".join(lines)
+            self.assertIn("lib.sh", text, name)
+            self.assertNotIn("/mnt/", text, name)
+            self.assertNotIn("/home/", text, name)
+
+    def test_lib_has_no_host_paths_or_secrets(self) -> None:
+        lib = (ROOT / "bin" / "stack" / "lib.sh").read_text()
+        self.assertIn("stack_start", lib)
+        self.assertIn("stack_start_assistant", lib)
+        self.assertIn("stack_stop", lib)
+        self.assertIn("stack_status", lib)
+        self.assertIn("qwen3.5:9b", lib)
+        self.assertIn("picoclaw agent", lib)
+        self.assertIn("--no-deps", lib)
+        self.assertIn("tools/list", lib)
+        self.assertNotIn("/mnt/", lib)
+        self.assertNotIn("/home/", lib)
+        self.assertNotIn("password", lib.lower())
+        self.assertNotIn("GITEA_TOKEN", lib)
+
+    def test_start_does_not_launch_picoclaw(self) -> None:
+        start = (ROOT / "bin" / "stack" / "start").read_text()
+        self.assertIn("stack_start", start)
+        self.assertNotIn("stack_start_assistant", start)
+        self.assertNotIn("picoclaw agent", start)
+
+    def test_start_assistant_attaches_agent(self) -> None:
+        src = (ROOT / "bin" / "stack" / "start-assistant").read_text()
+        self.assertIn("stack_start_assistant", src)
+        self.assertIn("--no-attach", src)
+
+    def test_stop_does_not_down_volumes(self) -> None:
+        lib = (ROOT / "bin" / "stack" / "lib.sh").read_text()
+        self.assertIn(" compose ", lib)
+        self.assertRegex(lib, r"\bstop\b")
+        self.assertNotIn(" compose down", lib)
+        self.assertNotIn("compose down", lib)
+
+    def test_docs_name_stack_commands(self) -> None:
+        runbook = (ROOT / "docs" / "runbook.md").read_text()
+        pico = (ROOT / "docs" / "picoclaw.md").read_text()
+        agents = (ROOT / "AGENTS.md").read_text()
+        for text in (runbook, pico, agents):
+            self.assertIn("bin/stack/start", text)
+            self.assertIn("bin/stack/start-assistant", text)
+            self.assertIn("bin/stack/status", text)
+            self.assertIn("bin/stack/stop", text)
+
+
+    def test_help_prints_comments_not_source(self) -> None:
+        r = subprocess.run(
+            [str(ROOT / "bin" / "stack" / "start"), "--help"],
+            cwd=str(ROOT),
+            capture_output=True,
+            text=True,
+            check=False,
+        )
+        self.assertEqual(r.returncode, 0, r.stderr)
+        self.assertIn("bin/stack/start", r.stdout)
+        self.assertNotIn("set -euo pipefail", r.stdout)
+        self.assertNotIn("source ", r.stdout)
+
+
+class StackFakePathTest(unittest.TestCase):
+    def _fake_bin(self, tmp: Path, *, health_ok: bool) -> Path:
+        bindir = tmp / "bin"
+        bindir.mkdir()
+        curl = bindir / "curl"
+        docker = bindir / "docker"
+        log = tmp / "docker.log"
+        curl.write_text(
+            f"""#!/usr/bin/env bash
+url=""
+for a in "$@"; do
+  case "$a" in http*) url=$a ;;
+  esac
+done
+if [ "{int(health_ok)}" = "0" ] && [[ "$url" == */health ]]; then
+  echo '{{"status":"down"}}'
+  exit 7
+fi
+case "$url" in
+  */mcp)
+    echo '{{"jsonrpc":"2.0","id":1,"result":{{"tools":[{{"name":"search"}},{{"name":"get"}},{{"name":"audit"}}]}}}}'
+    ;;
+  */api/tags)
+    echo '{{"models":[{{"name":"qwen3.5:9b"}}]}}'
+    ;;
+  */api/pull)
+    echo '{{"status":"success"}}'
+    ;;
+  *)
+    echo '{{"status":"ok"}}'
+    ;;
+esac
+"""
+        )
+        docker.write_text(
+            f"""#!/usr/bin/env bash
+echo "$*" >> "{log}"
+exit 0
+"""
+        )
+        curl.chmod(curl.stat().st_mode | stat.S_IEXEC)
+        docker.chmod(docker.stat().st_mode | stat.S_IEXEC)
+        return bindir
+
+    def _env(self, bindir: Path) -> dict[str, str]:
+        env = os.environ.copy()
+        env["PATH"] = f"{bindir}:{env.get('PATH', '')}"
+        env["STACK_WAIT_SECS"] = "1"
+        env["STACK_WAIT_INTERVAL"] = "0"
+        return env
+
+    def test_start_skips_compose_when_brain_healthy(self) -> None:
+        with tempfile.TemporaryDirectory() as raw:
+            tmp = Path(raw)
+            bindir = self._fake_bin(tmp, health_ok=True)
+            log = tmp / "docker.log"
+            r = subprocess.run(
+                [str(ROOT / "bin" / "stack" / "start")],
+                cwd=str(ROOT),
+                env=self._env(bindir),
+                capture_output=True,
+                text=True,
+                check=False,
+            )
+            self.assertEqual(r.returncode, 0, r.stderr)
+            self.assertFalse(log.exists(), "healthy brain must not docker compose up")
+
+    def test_start_ups_brain_when_unhealthy(self) -> None:
+        with tempfile.TemporaryDirectory() as raw:
+            tmp = Path(raw)
+            bindir = self._fake_bin(tmp, health_ok=False)
+            log = tmp / "docker.log"
+            r = subprocess.run(
+                [str(ROOT / "bin" / "stack" / "start")],
+                cwd=str(ROOT),
+                env=self._env(bindir),
+                capture_output=True,
+                text=True,
+                check=False,
+            )
+            self.assertNotEqual(r.returncode, 0, "unhealthy brain without recovering compose must fail")
+            self.assertTrue(log.exists(), r.stderr)
+            logged = log.read_text()
+            self.assertIn("up -d", logged)
+            self.assertIn("brain", logged)
+            self.assertNotIn("picoclaw", logged)
+
+    def test_stop_stops_named_services(self) -> None:
+        with tempfile.TemporaryDirectory() as raw:
+            tmp = Path(raw)
+            bindir = self._fake_bin(tmp, health_ok=True)
+            log = tmp / "docker.log"
+            r = subprocess.run(
+                [str(ROOT / "bin" / "stack" / "stop")],
+                cwd=str(ROOT),
+                env=self._env(bindir),
+                capture_output=True,
+                text=True,
+                check=False,
+            )
+            self.assertEqual(r.returncode, 0, r.stderr)
+            logged = log.read_text()
+            self.assertIn("stop", logged)
+            self.assertNotIn(" down", logged)
+            for svc in ("brain", "brain-mcp", "reasoner", "picoclaw"):
+                self.assertIn(svc, logged)
+
+    def test_start_assistant_no_attach_starts_picoclaw(self) -> None:
+        with tempfile.TemporaryDirectory() as raw:
+            tmp = Path(raw)
+            bindir = self._fake_bin(tmp, health_ok=True)
+            log = tmp / "docker.log"
+            r = subprocess.run(
+                [str(ROOT / "bin" / "stack" / "start-assistant"), "--no-attach"],
+                cwd=str(ROOT),
+                env=self._env(bindir),
+                capture_output=True,
+                text=True,
+                check=False,
+            )
+            self.assertEqual(r.returncode, 0, r.stderr + r.stdout)
+            logged = log.read_text() if log.exists() else ""
+            self.assertIn("picoclaw", logged)
+            self.assertIn("--no-deps", logged)
+            self.assertNotIn("picoclaw agent", logged)

bin/tools/test_system_perf.py

@@ -0,0 +1,36 @@
+"""qa/system_perf.py is an offline-gated system test (no live brain in CI)."""
+from __future__ import annotations
+
+import ast
+import unittest
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parents[2]
+
+
+class SystemPerfScriptTest(unittest.TestCase):
+    def test_script_compiles_and_is_read_only(self) -> None:
+        path = ROOT / "qa" / "system_perf.py"
+        src = path.read_text()
+        compile(src, str(path), "exec")
+        self.assertIn("--json", src)
+        self.assertIn("qwen3.5:9b", src)
+        self.assertIn("--picoclaw", src)
+        self.assertIn("BRAIN_URL", src)
+        self.assertIn("tools/list", src)
+        self.assertIn("tools/call", src)
+        self.assertIn("GATE_HEALTH_MS", src)
+        self.assertIn("GATE_GET_P50_MS", src)
+        self.assertNotIn("kb.lbug", src)
+        self.assertNotIn("password", src.lower())
+        self.assertNotIn("token", src.lower())
+
+    def test_script_does_not_write_ladybug(self) -> None:
+        tree = ast.parse((ROOT / "qa" / "system_perf.py").read_text())
+        writes = [
+            n.func.attr
+            for n in ast.walk(tree)
+            if isinstance(n, ast.Call) and isinstance(n.func, ast.Attribute)
+            and n.func.attr in {"write_text", "write_bytes", "dump"}
+        ]
+        self.assertEqual(writes, [], f"system_perf must not write files: {writes}")

bin/web/search.go

@@ -16,9 +16,9 @@ import (
 	"fmt"
 	"net/http"
 	"os"
-	"strconv"
 	"time"
 
+	"github.com/eSlider/2dph/internal/cli"
 	"github.com/eSlider/2dph/internal/websearch"
 	"golang.org/x/sys/unix"
 )
@@ -28,77 +28,15 @@ func main() {
 }
 
 func run(args []string) int {
-	var (
+	c, err := websearch.ParseArgs(args)
-		query, site, lang, fresh, category, engines string
-		limit                                       = websearch.DefaultLimit
-		jsonOut, refresh, force                     bool
-		ttl                                         = float64(websearch.CacheTTL)
-		timeout                                     = 25
-	)
-	i := 0
-	for i < len(args) {
-		a := args[i]
-		switch {
-		case a == "--json":
-			jsonOut = true
-		case a == "--refresh":
-			refresh = true
-		case a == "--force":
-			force = true
-		case (a == "-n" || a == "--limit") && i+1 < len(args):
-			i++
-			n, err := strconv.Atoi(args[i])
-			if err != nil || n < 0 {
-				fmt.Fprintln(os.Stderr, "web/search: --limit must be a non-negative integer")
-				return 2
-			}
-			limit = n
-		case a == "--site" && i+1 < len(args):
-			i++
-			site = args[i]
-		case a == "--lang" && i+1 < len(args):
-			i++
-			lang = args[i]
-		case a == "--fresh" && i+1 < len(args):
-			i++
-			fresh = args[i]
-		case a == "--category" && i+1 < len(args):
-			i++
-			category = args[i]
-		case a == "--engines" && i+1 < len(args):
-			i++
-			engines = args[i]
-		case a == "--ttl" && i+1 < len(args):
-			i++
-			v, err := strconv.ParseFloat(args[i], 64)
 	if err != nil {
-				fmt.Fprintln(os.Stderr, "web/search: --ttl must be a number")
+		return cli.Fail(err)
-				return 2
-			}
-			ttl = v
-		case a == "--timeout" && i+1 < len(args):
-			i++
-			n, err := strconv.Atoi(args[i])
-			if err != nil || n <= 0 {
-				fmt.Fprintln(os.Stderr, "web/search: --timeout must be a positive integer")
-				return 2
-			}
-			timeout = n
-		case a == "-h" || a == "--help":
-			fmt.Fprintln(os.Stderr, `usage: bin/web/search.go QUERY [--json] [-n N] [--site HOST] [--lang LANG] [--fresh day|week|month|year] [--category CAT] [--engines LIST] [--refresh] [--force]`)
-			return 0
-		case len(a) > 0 && a[0] != '-' && query == "":
-			query = a
-		default:
-			fmt.Fprintf(os.Stderr, "web/search: unknown flag %s\n", a)
-			return 2
-		}
-		i++
-	}
-	if query == "" {
-		fmt.Fprintln(os.Stderr, "web/search: query required")
-		return 2
 	}
+	query, site, lang, fresh, category, engines := c.Query, c.Site, c.Lang, c.Fresh, c.Category, c.Engines
+	limit := c.Limit
+	jsonOut, refresh, force := c.JSONOut, c.Refresh, c.Force
+	ttl := c.TTL
+	timeout := c.Timeout
 	if site != "" {
 		query = "site:" + site + " " + query
 	}

compose.yaml

@@ -1,66 +1,97 @@
 # 2dph — docker composition
 #
-#   docker compose run --rm brain index                     # rebuild graph
+#   bin/stack/start / start-assistant / status / stop
-#   docker compose run --rm brain search "Matrix fed"       # one-shot query
+#   docker compose up -d brain                  # API (Zig CGO serve)
-#   docker compose run --rm brain serve                     # async Go server
+#   docker compose --profile index run --rm index   # Python rebuild
-#   docker compose up brain-watch                           # auto re-index
+#   docker compose --profile picoclaw up -d     # brain-mcp + CPU reasoner + PicoClaw gateway
+#   docker compose --profile reasoner up -d reasoner   # CPU Ollama :11435
+#   docker compose --profile searxng up -d
+#   OCR_ENGINE=paddle docker compose --profile ocr-paddle run --rm ocr-paddle
 #
-# Caching: the 128M model (HF_HOME) and kb.lbug (VAR_DIR) live in named
+# Secrets never baked in: search.env + db-profiles.yml from ~/.config/brain.
-# volumes, so rebuilds never redownload the model or re-derive the graph.
-# Secrets are never baked into the image: search.env + db-profiles.yml mount
-# read-only from ~/.config/brain.
 
 name: 2dph
 
+networks:
+  default:
+    name: 2dph_sys
+    driver: bridge
+    ipam:
+      config:
+        - subnet: 10.23.42.0/24
+
 services:
   brain:
-    image: ghcr.io/eslider/2dph:latest
+    image: ghcr.io/eslider/2dph:api
     build:
       context: .
       dockerfile: Dockerfile
+      target: api
       cache_from:
         - ghcr.io/eslider/2dph:cache
-    command: ["brain", "search", "help"]
+    command: ["serve"]
     environment: &env
       HF_HOME: /data/hf
       BRAIN_SEARCH_CACHE: /data/cache/web-search.sqlite
       BRAIN_DB_PROFILES: /secret/db-profiles.yml
       BRAIN_SEARCH_ENV: /secret/search.env
-      KB_SEARCH_CMD: /app/bin/kb/search
+      KB_ROOT: /data
       KB_WORKERS: "4"
+      KB_PORT: "8630"
     volumes:
       - kb-model:/data/hf
       - kb-var:/data
-      # corpus is read-only on the host, never written from the container
-      - ..:/corpus:ro
       - ~/.config/brain:/secret:ro
+    ports:
+      - "127.0.0.1:8630:8630"
     read_only: true
     tmpfs:
       - /tmp
     healthcheck:
-      test: ["CMD", "python3", "-c", "import ladybug, model2vec, mistune; print('ok')"]
+      test: ["CMD", "wget", "-qO-", "http://127.0.0.1:8630/health"]
       interval: 30s
       timeout: 5s
       retries: 3
     restart: unless-stopped
     stop_grace_period: 20s
 
-  # watcher: re-index on corpus file change (watchdog script)
   brain-watch:
-    image: ghcr.io/eslider/2dph:latest
+    image: ghcr.io/eslider/2dph:api
     environment: *env
     volumes:
       - kb-model:/data/hf
       - kb-var:/data
       - ..:/corpus:ro
       - ~/.config/brain:/secret:ro
-    command: ["brain", "watch", "/corpus"]
+    command: ["watch", "/corpus"]
     read_only: true
     tmpfs:
       - /tmp
     restart: unless-stopped
     stop_grace_period: 20s
 
+  # Python write path (Ladybug rebuild). Not in the API image.
+  #   docker compose --profile index run --rm index
+  index:
+    profiles: ["index"]
+    image: ghcr.io/eslider/2dph:index
+    build:
+      context: .
+      dockerfile: Dockerfile
+      target: index
+    environment:
+      HF_HOME: /data/hf
+      KB_PY: python3
+    volumes:
+      - kb-model:/data/hf
+      - kb-var:/app/var
+      - ..:/corpus:ro
+      - ~/.config/brain:/secret:ro
+    command: ["index"]
+    read_only: true
+    tmpfs:
+      - /tmp
+
   # Optional local SearXNG (D3). Skip if BRAIN_SEARCH_URL already points at a
   # live instance — do not run a second copy on that host.
   #   SEARXNG_SECRET=$(openssl rand -hex 32) docker compose --profile searxng up -d
@@ -76,18 +107,17 @@ services:
       - ./deploy/searxng/limiter.toml:/etc/searxng/limiter.toml:ro
     restart: unless-stopped
 
-  # MCP endpoint for an external agent (PicoClaw is not shipped here).
+  # MCP endpoint for PicoClaw (and any MCP client).
-  #   docker compose --profile picoclaw up brain-mcp
+  #   docker compose --profile picoclaw up -d
-  # Point the agent at http://127.0.0.1:8630/mcp (see deploy/picoclaw/).
   brain-mcp:
     profiles: ["picoclaw"]
-    image: ghcr.io/eslider/2dph:latest
+    image: ghcr.io/eslider/2dph:api
     environment: *env
     volumes:
       - kb-model:/data/hf
       - kb-var:/data
       - ~/.config/brain:/secret:ro
-    command: ["brain", "serve"]
+    command: ["serve"]
     ports:
       - "127.0.0.1:8630:8630"
     read_only: true
@@ -95,6 +125,53 @@ services:
       - /tmp
     restart: unless-stopped
 
+  # CPU OpenAI-compatible sidecar (D18). Weights are pulled at runtime, not
+  # baked into the 2dph image. Does not touch host Ollama on :11434.
+  #   docker compose --profile reasoner up -d reasoner
+  #   docker compose --profile reasoner exec reasoner ollama pull qwen3.5:9b
+  reasoner:
+    profiles: ["reasoner", "picoclaw"]
+    image: docker.io/ollama/ollama:latest
+    environment:
+      OLLAMA_NUM_GPU: "0"
+      OLLAMA_HOST: "0.0.0.0:11434"
+    ports:
+      - "127.0.0.1:11435:11434"
+    volumes:
+      - reasoner-ollama:/root/.ollama
+    restart: unless-stopped
+
+  # Official PicoClaw gateway. Config has no secrets (Ollama + HTTP MCP).
+  # Host network: brain/reasoner bind 127.0.0.1 only, so host.docker.internal
+  # (docker0) cannot reach them. Gateway 127.0.0.1:18790 (not the 18800 launcher).
+  # If :8630/:11435 are already bound, do not start brain-mcp/reasoner:
+  #   docker compose --profile picoclaw up -d --no-deps picoclaw
+  picoclaw:
+    profiles: ["picoclaw"]
+    image: docker.io/sipeed/picoclaw:v0.3.1
+    network_mode: host
+    depends_on:
+      - brain-mcp
+      - reasoner
+    environment:
+      PICOCLAW_GATEWAY_HOST: "127.0.0.1"
+    entrypoint: ["picoclaw", "gateway"]
+    volumes:
+      - picoclaw-home:/root/.picoclaw
+      - ./deploy/picoclaw/config.json:/root/.picoclaw/config.json:ro
+    restart: unless-stopped
+
+  # Optional PP-OCRv5 (not default). Default OCR is tesseract eng+deu.
+  #   OCR_ENGINE=paddle docker compose --profile ocr-paddle run --rm ocr-paddle
+  ocr-paddle:
+    profiles: ["ocr-paddle"]
+    image: python:3.12-slim
+    environment:
+      OCR_ENGINE: paddle
+    command: ["python", "-c", "print('OCR_ENGINE=paddle; install paddleocr on PATH')"]
+
 volumes:
   kb-model:
   kb-var:
+  reasoner-ollama:
+  picoclaw-home:

deploy/picoclaw/config.json

@@ -0,0 +1,33 @@
+{
+  "agents": {
+    "defaults": {
+      "model_name": "qwen3.5-9b",
+      "max_tool_iterations": 8,
+      "max_tokens": 512,
+      "context_window": 8192
+    }
+  },
+  "model_list": [
+    {
+      "model_name": "qwen3.5-9b",
+      "model": "ollama/qwen3.5:9b",
+      "api_base": "http://127.0.0.1:11435/v1",
+      "request_timeout": 600
+    }
+  ],
+  "tools": {
+    "web": {
+      "enabled": false
+    },
+    "mcp": {
+      "enabled": true,
+      "servers": {
+        "2dph": {
+          "enabled": true,
+          "type": "http",
+          "url": "http://127.0.0.1:8630/mcp"
+        }
+      }
+    }
+  }
+}

docs/README.md

@@ -1,15 +1,38 @@
-# 2dph (deductionphile)
+---
+type: reference
+status: current
+related:
+  - docs/runbook.md
+  - docs/design.md
+  - PLAN.md
+  - docs/roadmap.md
+---
 
-Evidence-first knowledge graph + hybrid RAG over the operational
+# 2dph docs (Diataxis)
-Brain/ops/eSlider stack. Facts need proof or they are
+
+Evidence-first knowledge graph. Facts need proof or they are
 `(not confirmed)`.
 
-- [PLAN.md](../PLAN.md) — decisions, execution order, open questions (v2)
+| Type | Doc |
-- [design](design.md) — schema, deduction model, sources
+|------|-----|
-- [Gitea issues](https://git.produktor.io/eSlider/2dph/issues) — work board (origin)
+| tutorial / howto | [runbook](runbook.md) — run anywhere (uv, Go, Docker) |
+| explanation | [design](design.md) — two roots, deduction, D17/D20/D18 |
+| explanation | [roadmap](roadmap.md) — gap to v1 (epic #16) |
+| howto | [picoclaw](picoclaw.md) — MCP agent (`bin/stack/start-assistant`) |
+| howto | [reasoner](reasoner.md) — CPU bake-off (D18) |
+| reference | [PLAN.md](../PLAN.md) — decisions D1–D24 |
+
+Decisions the public face must name: **D3** SearXNG compose, **D6** Go service /
+Python write sidecar, **D14** `bin/{subject}/{method}.go`, **D15** Gitea origin,
+**D17** assertion gate (facts → info → web), **D18** pluggable reasoner.
 
 Search: `bin/brain/search.go "query"` (HTTP: `bin/brain/serve.go` —
-`/health` `/search` `/get` `/stats` `/audit` `/ingest`). `--hop` is
+`/health` `/search` `/get` `/stats` `/audit` `/ingest`). `--hop N` walks
-not a walk; the flag errors until File/FROM_FILE edges exist.
+`FROM_FILE` → Commit → Person from each hit (max 3). Rebuild writes
+File edges ([#17](https://git.produktor.io/eSlider/2dph/issues/17)).
 
-Published docs live here and mirror the project state.
+Work board: [Gitea issues](https://git.produktor.io/eSlider/2dph/issues)
+([epic #16](https://git.produktor.io/eSlider/2dph/issues/16)).
+PRs and CI: GitHub [`eSlider/2dph`](https://github.com/eSlider/2dph).
+
+Published docs live here and match live commands.

docs/chat-import-plan.md

@@ -21,4 +21,5 @@ OO_CLI                     (default: $HOME/go/bin/oo)
 ./bin/chats/apply.go --dry-run
 ```
 
-JSONL → markdown only. Brain ingest is `bin/brain/index.go` (not a `chats index`).
+JSONL → markdown only. Brain ingest is `bin/brain/index.go --with-chats`
+(default `var/chats/md`). WhatsApp sync is out of v1.

docs/design.md

@@ -1,3 +1,12 @@
+---
+type: explanation
+status: current
+related:
+  - docs/README.md
+  - docs/runbook.md
+  - docs/roadmap.md
+---
+
 # Design — facts, info, deduction
 
 ## Two roots, one transaction
@@ -25,8 +34,13 @@ bin/brain/search.go "question"
      is not evidence of absence; `--no-web` / `--root` skip it)
 ```
 
-`--hop` is not implemented yet (needs File/FROM_FILE edges). The flag is an
+`--hop N` walks `Leaf-[:FROM_FILE]->File-[:HAS_VERSION]->Commit-[:AUTHORED]->Person`
-error; it is not a graph walk.
+from each hit (1=File, 2=Commit, 3=Person). Rebuild writes FROM_FILE;
+git import writes HAS_VERSION/AUTHORED ([#17](https://git.produktor.io/eSlider/2dph/issues/17)).
+
+Go CLIs parse with **flaggy** via `internal/cli` (D23). Flags may appear
+after positionals (`search q --hop 1`). Completions:
+`source <(./bin/cli/complete.go bash)`.
 
 ## Who / What / How / Where / When + evidence
 
@@ -54,6 +68,15 @@ binary); conversion prints leafs, brain write is `bin/brain/index.go`.
 `bin/facts/audit stale` flags leafs whose observed revision is behind the
 corpus HEAD.
 
+Fact **interval of truth** (D24 / OQ5): leaf props `valid_from` /
+`valid_to` (YYYY-MM-DD, inclusive; empty end = open; both empty = legacy
+always-active). `bin/brain/search.go --as-of YYYY-MM-DD` and MCP/HTTP
+`as_of` keep hits whose interval covers that day. This is not D16
+`temporal_freshness` (source freshness vs HEAD). [#36](https://git.produktor.io/eSlider/2dph/issues/36).
+Existing `kb.lbug` without the columns: open/search/add runs an idempotent
+`ALTER TABLE Leaf ADD …` (no full rebuild required). Fresh `--rebuild` still
+creates them in `CREATE NODE TABLE`.
+
 ## Sources (auto-pairing)
 
 - A: runtime state — `docker ps` (container running), ports actually bound
@@ -61,19 +84,36 @@ corpus HEAD.
 - C: narrative — READMEs, AGENTS.md, docs
 
 Confirmed = A×B or B×C agreement. Single source = hypothesis + `(not confirmed)`.
-Conflicting pairings (≥2 yes vs ≥2 no) = hypothesis (OQ1 → v2 resolution).
+Conflicting pairings (≥2 yes vs ≥2 no) stay hypothesis until
+`temporal_freshness` or `authority_pairing` fires (`bin/facts/audit contradict`,
+[#29](https://git.produktor.io/eSlider/2dph/issues/29)).
 
 ## Read path
 
 `bin/brain/get.go`, `stats.go`, and `eval.go` call `internal/brain` with cgo
-(`system_ladybug`). They do not exec Python. Control questions for recall@5
+(`system_ladybug`), compiled by **Zig** (`bin/cgo/zcc`, D21), not gcc.
-live in `internal/brain/rank` so CI can test the table without libladybug.
+They do not exec Python. Control questions for recall@5 live in
+`internal/brain/rank` so CI can test the table without libladybug.
 Python `bin/kb/{get,stats,eval}` remain for GitHub Actions until the runner
-has ladybug cgo. Index/write is still `bin/kb/index`.
+fetches Zig + libs (`bin/cgo/zig`). Incremental write is `bin/kb/add`
+(`bin/brain/add.go`). Bulk index/write is still `bin/kb/index`
+(`docker compose --profile index`).
 
 ## Agent API (D20)
 
 `bin/brain/serve.go` exposes the same `internal/httpapi.Ops` table as OpenAPI
 (`GET /openapi.json`) and MCP (`POST /mcp` JSON-RPC `tools/list` +
-`tools/call`). Tool names match paths: `search`, `get`, `stats`, `audit`.
+`tools/call`). Tool names match paths: `search`, `get`, `stats`, `audit`,
+`ingest` (add a leaf; omit body for the CLI hint).
 Agents should use these endpoints instead of shebang CLIs.
+
+## Reasoner (D18)
+
+Pluggable OpenAI-compatible URL. RAM: `Qwen/Qwen3.5-9B`. Quality:
+`prism-ml/Bonsai-27B-gguf` or `Qwen/Qwen3.6-27B`. No official Qwen3.6-9B.
+CPU sidecar: compose profile `reasoner` (`OLLAMA_NUM_GPU=0`,
+`127.0.0.1:11435`). Bake-off: `bin/reasoner/bakeoff.go`. Weights stay out
+of the 2dph image. See [docs/reasoner.md](reasoner.md).
+
+Gap to v1 (hops, corpus, CI eval): [roadmap](roadmap.md),
+[epic #16](https://git.produktor.io/eSlider/2dph/issues/16).

docs/picoclaw.md

@@ -1,18 +1,46 @@
 # PicoClaw profile (reference agent)
 
-2dph is the memory/fact gate. PicoClaw (or any MCP client) is the agent loop
+2dph is the memory/fact gate. Compose profile `picoclaw` runs the official
-and is **not** shipped in this repo.
+PicoClaw gateway (`docker.io/sipeed/picoclaw:v0.3.1`) plus `brain-mcp` and the
+CPU reasoner. Default agent model is `qwen3.5:9b` (RAM path, D18). Weights stay
+in the reasoner volume, not in the 2dph image.
+No secrets in git: Ollama needs no key; MCP is local HTTP.
 
 ```bash
-docker compose --profile picoclaw up brain-mcp
+bin/stack/start-assistant
+bin/stack/start-assistant --no-attach
+bin/stack/start-assistant -- -m "search the 2dph brain for LadybugDB"
+bin/stack/status
+bin/stack/stop
 ```
 
-The API listens on `127.0.0.1:8630`. Point the agent at
+`start-assistant` reuses a healthy brain on `:8630`, starts the CPU reasoner,
-`http://127.0.0.1:8630/mcp` using [deploy/picoclaw/mcp.json.example](../deploy/picoclaw/mcp.json.example).
+pulls `qwen3.5:9b` if missing, brings up the gateway with `--no-deps picoclaw`,
+then `picoclaw agent` (MCP `search` → `get` → `audit`). Gateway-only Compose:
+
+```bash
+docker compose --profile picoclaw up -d
+# already serving :8630 / :11435:
+docker compose --profile picoclaw up -d --no-deps picoclaw
+```
+
+Gateway: `127.0.0.1:18790`. Brain MCP: `http://127.0.0.1:8630/mcp`.
+Cursor-style clients can use [deploy/picoclaw/mcp.json.example](../deploy/picoclaw/mcp.json.example).
+PicoClaw itself uses [deploy/picoclaw/config.json](../deploy/picoclaw/config.json)
+(`127.0.0.1` + host network — loopback publishes are not reachable via docker0).
 
 OpenAPI: `GET http://127.0.0.1:8630/openapi.json`.
 
 Before a factual reply: `search` → `get` → `audit`. `throttled` is not a
 negative finding. See `skills/picoclaw/SKILL.md`.
 
-No Cursor required. A live PicoClaw binary/image is an operator choice.
+System performance (MCP gates + qwen3.5:9b tool_call + PicoClaw gateway):
+
+```bash
+./qa/system_perf.py --json | yq '.gates'
+REASONER_MODEL=qwen3.5:9b ./qa/system_perf.py --reasoner --picoclaw --json | yq '.reasoner'
+```
+
+The default agent model is `qwen3.5:9b`. PicoClaw `context_window` is 8192
+(heuristic `max_tokens*4` at 512 is 2048, too small for MCP tool schemas).
+`request_timeout` is 600s for a CPU turn (tool_call + MCP search + answer).

docs/reasoner.md

@@ -0,0 +1,71 @@
+# Reasoner bake-off (D18)
+
+Pluggable OpenAI-compatible URL. 2dph does not ship weights. PicoClaw is
+compose profile `picoclaw` (`sipeed/picoclaw`); the bake-off hits the same
+tool names (`search` → `get` → `audit` from `internal/httpapi.Ops`).
+
+```bash
+docker compose --profile reasoner up -d reasoner
+docker compose --profile reasoner exec reasoner ollama pull qwen3.5:9b
+REASONER_BASE_URL=http://127.0.0.1:11435/v1 REASONER_MODEL=qwen3.5:9b \
+  ./bin/reasoner/bakeoff.go --json
+```
+
+JSON includes `latency_p50_ms` / `latency_p95_ms` from DuckDB (`internal/duckstats`, D22).
+
+Host Ollama on `:11434` is left alone. This sidecar binds `127.0.0.1:11435`
+with `OLLAMA_NUM_GPU=0` (CPU). Measure RSS (`/api/ps` `size`), not VRAM.
+
+If Compose cannot allocate a project network (Docker IPAM pool exhausted),
+the same sidecar is:
+
+```bash
+docker run -d --name 2dph-reasoner \
+  -e OLLAMA_NUM_GPU=0 \
+  -p 127.0.0.1:11435:11434 \
+  -v 2dph-reasoner-ollama:/root/.ollama \
+  ollama/ollama:latest
+```
+
+## Real Hugging Face ids
+
+| Role | HF id | Ollama tag (this bake-off) |
+|------|-------|----------------------------|
+| RAM / 9B | `Qwen/Qwen3.5-9B` | `qwen3.5:9b` |
+| Quality 27B (CPU) | `prism-ml/Bonsai-27B-gguf` (derived from Qwen3.6-27B) | `MichelRosselli/bonsai-27b:Q1_0` |
+| Quality 27B (full) | `Qwen/Qwen3.6-27B` | not pulled on this CPU box |
+
+There is **no official Qwen3.6-9B**. Do not invent that id.
+
+Qwen3.5-9B has documented upstream tool-call XML bugs. A 9B win on tools
+is only claimed if this bake-off records OpenAI `tool_calls` (not
+`<tool_call>` XML in `content`).
+
+The 2dph API image does not `COPY` GGUF/safetensors. Pull at runtime into
+the `reasoner-ollama` volume.
+
+## Live CPU run
+
+Host sidecar: Ollama **0.32.9**, `OLLAMA_NUM_GPU=0`, `127.0.0.1:11435`,
+`device: cpu`, `vram_mb: 0`. Date: 2026-08-13. Same three prompts
+(`search` / `get` / `audit`). PicoClaw binary was not used; the OpenAI
+tools payload is the surface it would send.
+
+| Model | HF id | tool_call | xml_leak | rss_mb | latency_ms (search/get/audit) |
+|-------|-------|-----------|----------|--------|-------------------------------|
+| `qwen3.5:9b` | `Qwen/Qwen3.5-9B` | 3/3 | 0 | 5790 | 50059 / 51678 / 31980 |
+| `MichelRosselli/bonsai-27b:Q1_0` | `prism-ml/Bonsai-27B-gguf` | 3/3 | 0 | 21951 | 327702 / 166830 / 119808 |
+| `Qwen/Qwen3.6-27B` | `Qwen/Qwen3.6-27B` | not loaded | — | — | too heavy for this CPU box |
+
+Both loaded models emitted OpenAI `tool_calls` (not `<tool_call>` XML) on
+this runtime. **Do not claim 9B is better at tools** — the score is tied
+at 3/3. 9B is smaller and faster. Bonsai RSS includes weights + KV
+(`size` from `/api/ps`); first Bonsai prompt includes cold load.
+
+Re-run:
+
+```bash
+REASONER_BASE_URL=http://127.0.0.1:11435/v1 REASONER_MODEL=qwen3.5:9b \
+  ./bin/reasoner/bakeoff.go --json
+REASONER_MODEL=MichelRosselli/bonsai-27b:Q1_0 ./bin/reasoner/bakeoff.go --json
+```

docs/roadmap.md

@@ -0,0 +1,71 @@
+---
+type: explanation
+status: current
+related:
+  - PLAN.md
+  - docs/design.md
+  - docs/runbook.md
+---
+
+# Gap to v1 — detective brain
+
+Goal: a brain that does not assert without proof. Search is deduction
+(`facts` ≥2 sources → `info` → `web`). `confirmed` only from the facts root.
+
+**v1 is a living graph the agent can write and walk**, not “more RAG”.
+
+Epic: [Gitea #16](https://git.produktor.io/eSlider/2dph/issues/16).
+Milestone: [v1 detective brain](https://git.produktor.io/eSlider/2dph/milestone/12).
+Decisions: [PLAN.md](../PLAN.md).
+
+## In (do not reopen)
+
+Read path Go + Zig CGO (D21). HTTP + OpenAPI + MCP (D20). PicoClaw compose
+profile + CPU reasoner (D18). Mail sync → import → rebuild. D14 shebangs.
+Compose `api` (no CPython) / `index` (Python write). Issues #1–#5, #7–#13.
+[#15](https://git.produktor.io/eSlider/2dph/issues/15) lever/loop.
+[#14](https://git.produktor.io/eSlider/2dph/issues/14) `bin/brain/add.go` /
+`POST /ingest` (Python `kblib.add_leafs`; no Go upsert port).
+[#17](https://git.produktor.io/eSlider/2dph/issues/17) `--hop N` walks
+FROM_FILE / HAS_VERSION / AUTHORED.
+[#18](https://git.produktor.io/eSlider/2dph/issues/18) `--with-facts` /
+`--with-chats` on rebuild (WhatsApp out of v1).
+[#19](https://git.produktor.io/eSlider/2dph/issues/19) CI recall SoT =
+`bin/brain/eval.go` via Zig.
+Epic [#16](https://git.produktor.io/eSlider/2dph/issues/16) closed.
+
+## v2
+
+[#6](https://git.produktor.io/eSlider/2dph/issues/6) OCR — **in**.
+[#30](https://git.produktor.io/eSlider/2dph/issues/30) OQ3 duckdb-go — **in**.
+[#29](https://git.produktor.io/eSlider/2dph/issues/29) OQ1 contradiction
+resolution — **in** (`temporal_freshness`, `authority_pairing`).
+[#34](https://git.produktor.io/eSlider/2dph/issues/34) D23 flaggy CLI — **in**.
+[#36](https://git.produktor.io/eSlider/2dph/issues/36) OQ5/D24 fact intervals /
+as-of — **in** (not D16 `temporal_freshness`).
+
+## Blockers
+
+None for epic #16 (closed). Remaining v2: OQ4 (deferred).
+
+```
+question
+    │
+    ├─ FTS + HNSW          ← in
+    ├─ facts / info roots  ← in
+    ├─ web (D17)           ← in
+    ├─ brain/add ACID      ← in
+    ├─ Cypher hop          ← in
+    └─ facts+chats corpus  ← in
+```
+
+## Not v1
+
+OQ4 YAML-first leafs.
+OQ5/D24 fact intervals + as-of — **in**
+([#36](https://git.produktor.io/eSlider/2dph/issues/36)).
+OCR (OQ2), duckdb-go (OQ3/D22), and D16 adjudication (OQ1) are in.
+
+## Close epic #16 when
+
+Children #14, #15, #17, #18, #19 are closed. MCP tool order stays gated by tests.

docs/runbook.md

@@ -0,0 +1,100 @@
+---
+type: howto
+status: current
+related:
+  - docs/README.md
+  - PLAN.md
+---
+
+# Run 2dph (portable)
+
+No laptop-absolute paths. Config lives in env files under `$HOME/.config/brain/`
+(mode 0600), not in git.
+
+## Toolchain
+
+- Go (see `go.mod`)
+- Python 3.12 + [uv](https://docs.astral.sh/uv)
+- Optional: Docker, Zig CGO via `bin/cgo/zig` (not gcc)
+- Optional: poppler (`pdftotext`/`pdftoppm`) + tesseract `eng+deu` for mail OCR
+
+```bash
+uv venv .venv
+uv pip install -r requirements.lock.txt
+eval "$(bin/cgo/zig env)"   # when compiling Ladybug read tools
+go test ./...
+uv run python -m unittest discover -s bin/tools -t .
+```
+
+## Config
+
+| File / env | Purpose |
+|------------|---------|
+| `$BRAIN_SEARCH_ENV` (default `$HOME/.config/brain/search.env`) | `BRAIN_SEARCH_URL` (SearXNG). Optional Basic Auth. |
+| `$HOME/.config/brain/db-profiles.yml` | read-only Postgres profiles (OnlyOffice via tunnel) |
+
+If the host already runs SearXNG, point `BRAIN_SEARCH_URL` at it. Do not start
+a second copy (D3). Optional Compose instance:
+
+```bash
+SEARXNG_SECRET=$(openssl rand -hex 32) docker compose --profile searxng up -d
+```
+
+That binds `127.0.0.1:8888`. JSON format must stay enabled.
+
+## Index then search
+
+Write path is `bin/brain/add.go` for a leaf (or `POST /ingest`). Bulk
+corpus rebuild remains `bin/brain/index.go --rebuild` (Compose profile
+`index`). Do not DROP INDEX on Ladybug 0.19.
+
+```bash
+bin/brain/add.go --text "arc-1 runs Matrix" --root facts --source "compose.yml x docker ps"
+bin/brain/index.go --rebuild --with-facts --with-chats
+bin/brain/search.go "LadybugDB vector index"     # facts → info → web (D17)
+bin/brain/search.go "upstream flag" --no-web
+bin/brain/search.go "who works where" --as-of 2025-01-01  # D24 intervals
+source <(./bin/cli/complete.go bash)            # D23 flaggy complete
+bin/brain/get.go <id> --body
+bin/brain/stats.go
+```
+
+`--hop N` walks File → Commit → Person from each hit. `--as-of YYYY-MM-DD`
+keeps leafs whose `valid_from`/`valid_to` cover that day (empty interval =
+legacy always-on). Empty web results are `throttled`, not absence.
+Gap to v1: [roadmap](roadmap.md) / [epic #16](https://git.produktor.io/eSlider/2dph/issues/16).
+
+Ladybug 0.19: never `DROP INDEX` FTS/VECTOR (ghost catalog). Fresh indexes =
+delete `var/kb.lbug` then `--rebuild`.
+
+## HTTP / MCP
+
+```bash
+bin/stack/start                 # brain :8630, wait until MCP search/get/audit
+bin/stack/status                # YAML: brain / reasoner / picoclaw
+bin/stack/start-assistant       # + qwen3.5:9b + PicoClaw agent (ask the brain)
+bin/stack/start-assistant --no-attach
+bin/stack/stop                  # compose stop; volumes kept
+```
+
+Same Compose services by hand:
+
+```bash
+docker compose up -d brain                       # :8630 Zig CGO serve
+docker compose --profile index run --rm index    # rebuild
+docker compose --profile picoclaw up brain-mcp   # MCP 127.0.0.1:8630
+```
+
+`GET /openapi.json`, `POST /mcp`. Agent tool order: `search` → `get` → `audit`.
+See [picoclaw.md](picoclaw.md).
+
+## Reasoner (optional, D18)
+
+CPU sidecar on `127.0.0.1:11435`. Weights are not in the 2dph image.
+
+```bash
+docker compose --profile reasoner up -d reasoner
+REASONER_BASE_URL=http://127.0.0.1:11435/v1 ./bin/reasoner/bakeoff.go --json
+```
+
+See [reasoner.md](reasoner.md).

go.mod

@@ -7,7 +7,9 @@ require (
 	github.com/arran4/golang-ical v0.3.5
 	github.com/chewxy/math32 v1.11.2
 	github.com/daulet/tokenizers v1.27.0
+	github.com/duckdb/duckdb-go/v2 v2.10505.0
 	github.com/go-git/go-git/v5 v5.19.2
+	github.com/integrii/flaggy v1.8.0
 	golang.org/x/sys v0.47.0
 	golang.org/x/text v0.40.0
 	modernc.org/sqlite v1.56.0
@@ -20,10 +22,17 @@ require (
 	github.com/apache/arrow-go/v18 v18.6.0 // indirect
 	github.com/cloudflare/circl v1.6.3 // indirect
 	github.com/cyphar/filepath-securejoin v0.6.1 // indirect
+	github.com/duckdb/duckdb-go-bindings v0.10505.0 // indirect
+	github.com/duckdb/duckdb-go-bindings/lib/darwin-amd64 v0.10505.0 // indirect
+	github.com/duckdb/duckdb-go-bindings/lib/darwin-arm64 v0.10505.0 // indirect
+	github.com/duckdb/duckdb-go-bindings/lib/linux-amd64 v0.10505.0 // indirect
+	github.com/duckdb/duckdb-go-bindings/lib/linux-arm64 v0.10505.0 // indirect
+	github.com/duckdb/duckdb-go-bindings/lib/windows-amd64 v0.10505.0 // indirect
 	github.com/dustin/go-humanize v1.0.1 // indirect
 	github.com/emirpasic/gods v1.18.1 // indirect
 	github.com/go-git/gcfg v1.5.1-0.20230307220236-3a3c6141e376 // indirect
 	github.com/go-git/go-billy/v5 v5.9.0 // indirect
+	github.com/go-viper/mapstructure/v2 v2.5.0 // indirect
 	github.com/goccy/go-json v0.10.6 // indirect
 	github.com/golang/groupcache v0.0.0-20241129210726-2c02b8208cf8 // indirect
 	github.com/google/flatbuffers v25.12.19+incompatible // indirect

go.sum

@@ -31,6 +31,20 @@ github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSs
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc h1:U9qPSI2PIWSS1VwoXQT9A3Wy9MM3WgvqSxFWenqJduM=
 github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/duckdb/duckdb-go-bindings v0.10505.0 h1:/0pPsTLrcCsTGxT0VrHgJWnOcPe1tQL1vrki1v3jbAI=
+github.com/duckdb/duckdb-go-bindings v0.10505.0/go.mod h1:HoD5xePkDj3VZbBnVVfxVVYIljZ9khCprWA7FgwIiC4=
+github.com/duckdb/duckdb-go-bindings/lib/darwin-amd64 v0.10505.0 h1:FrMqquFBQlMsi34h2KZgCku54rqA8xEbXZ0NLVDKwYs=
+github.com/duckdb/duckdb-go-bindings/lib/darwin-amd64 v0.10505.0/go.mod h1:EnAvZh1kNJHp5yF+M1ZHNEvapnmt6anq1xXHVrAGqMo=
+github.com/duckdb/duckdb-go-bindings/lib/darwin-arm64 v0.10505.0 h1:lbRbpQwT1MmUhh/VTwukV9K8bxKByV3UghAP3MvsbBo=
+github.com/duckdb/duckdb-go-bindings/lib/darwin-arm64 v0.10505.0/go.mod h1:IGLSeEcFhNeZF16aVjQCULD7TsFZKG5G7SyKJAXKp5c=
+github.com/duckdb/duckdb-go-bindings/lib/linux-amd64 v0.10505.0 h1:nrsaVYj3XYCRbS2FpdOMD/KHE7egRMr+/NR1IHmjT84=
+github.com/duckdb/duckdb-go-bindings/lib/linux-amd64 v0.10505.0/go.mod h1:KAIynZ0GHCS7X5fRyuFnQMg/SZBPK/bS9OCOVojClxw=
+github.com/duckdb/duckdb-go-bindings/lib/linux-arm64 v0.10505.0 h1:qM6oGDgwXBILJGbTY4fCy6QOczLpucUA6yn6g3ORjh4=
+github.com/duckdb/duckdb-go-bindings/lib/linux-arm64 v0.10505.0/go.mod h1:81SGOYoEUs8qaAfSk1wRfM5oobrIJ5KI7AzYhK6/bvQ=
+github.com/duckdb/duckdb-go-bindings/lib/windows-amd64 v0.10505.0 h1:DjqZl9rYreHkSOqnqLmkrqH5T8UdQNcxZLJVZzGmXXA=
+github.com/duckdb/duckdb-go-bindings/lib/windows-amd64 v0.10505.0/go.mod h1:K25pJL26ARblGDeuAkrdblFvUen92+CwksLtPEHRqqQ=
+github.com/duckdb/duckdb-go/v2 v2.10505.0 h1:SWwvLn2Qx/RQSnQNupwgIF8VbnJ5A6OQU9lYb/mDETI=
+github.com/duckdb/duckdb-go/v2 v2.10505.0/go.mod h1:m0PW4J4FG9hlFlVdXi6Ds9owpyIDaBdE2jyce00fGcE=
 github.com/dustin/go-humanize v1.0.1 h1:GzkhY7T5VNhEkwH0PVJgjz+fX1rhBrR7pRT3mDkpeCY=
 github.com/dustin/go-humanize v1.0.1/go.mod h1:Mu1zIs6XwVuF/gI1OepvI0qD18qycQx+mFykh5fBlto=
 github.com/elazarl/goproxy v1.7.2 h1:Y2o6urb7Eule09PjlhQRGNsqRfPmYI3KKQLFpCAV3+o=
@@ -47,6 +61,8 @@ github.com/go-git/go-git-fixtures/v4 v4.3.2-0.20231010084843-55a94097c399 h1:eMj
 github.com/go-git/go-git-fixtures/v4 v4.3.2-0.20231010084843-55a94097c399/go.mod h1:1OCfN199q1Jm3HZlxleg+Dw/mwps2Wbk9frAWm+4FII=
 github.com/go-git/go-git/v5 v5.19.2 h1:wkfn7vOlUBu8ivAWKBWisTiwJK4jYHzTF8Ndv1LyGqY=
 github.com/go-git/go-git/v5 v5.19.2/go.mod h1:QqCBE1EFN5ddFmrliLQ3/ntRCUjZU3EJuwuB/jWEHjk=
+github.com/go-viper/mapstructure/v2 v2.5.0 h1:vM5IJoUAy3d7zRSVtIwQgBj7BiWtMPfmPEgAXnvj1Ro=
+github.com/go-viper/mapstructure/v2 v2.5.0/go.mod h1:oJDH3BJKyqBA2TXFhDsKDGDTlndYOZ6rGS0BRZIxGhM=
 github.com/goccy/go-json v0.10.6 h1:p8HrPJzOakx/mn/bQtjgNjdTcN+/S6FcG2CTtQOrHVU=
 github.com/goccy/go-json v0.10.6/go.mod h1:oq7eo15ShAhp70Anwd5lgX2pLfOS3QCiwU/PULtXL6M=
 github.com/golang/groupcache v0.0.0-20241129210726-2c02b8208cf8 h1:f+oWsMOmNPc8JmEHVZIycC7hBoQxHH9pNKQORJNozsQ=
@@ -61,6 +77,8 @@ github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
 github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/hashicorp/golang-lru/v2 v2.0.7 h1:a+bsQ5rvGLjzHuww6tVxozPZFVghXaHOwFs4luLUK2k=
 github.com/hashicorp/golang-lru/v2 v2.0.7/go.mod h1:QeFd9opnmA6QUJc5vARoKUSoFhyfM2/ZepoAG6RGpeM=
+github.com/integrii/flaggy v1.8.0 h1:tC1qWwg4fhF2Qdaj+MpPK04cxlOSq0+HoMZqAW6Arao=
+github.com/integrii/flaggy v1.8.0/go.mod h1:QS4c80m87SXG0pmVUT/Lx2RY5EbkLvLp7IKBD2jwcFA=
 github.com/jbenet/go-context v0.0.0-20150711004518-d14ea06fba99 h1:BQSFePA1RWJOlocH6Fxy8MmwDt+yVQYULKfN0RoTN8A=
 github.com/jbenet/go-context v0.0.0-20150711004518-d14ea06fba99/go.mod h1:1lJo3i6rXxKeerYnT8Nvf0QmHCRC1n8sfWVwXF2Frvo=
 github.com/kevinburke/ssh_config v1.2.0 h1:x584FjTGwHzMwvHx18PXxbBVzfnxogHaAReU4gf13a4=

internal/brain/db.go

@@ -85,9 +85,18 @@ func openWithSandbox(epsv string) error {
 		closeBrain()
 		return fmt.Errorf("LOAD EXTENSION VECTOR: %w", err)
 	}
+	migrateIntervalColumns()
 	return nil
 }
 
+// migrateIntervalColumns adds D24 valid_from/valid_to on existing Leaf tables.
+// Fresh CREATE already has them; ALTER is a no-op when the column exists.
+func migrateIntervalColumns() {
+	for _, col := range []string{"valid_from", "valid_to"} {
+		_, _ = conn.Query("ALTER TABLE Leaf ADD " + col + " STRING")
+	}
+}
+
 func closeBrain() {
 	if conn != nil {
 		conn.Close()

internal/brain/http.go

@@ -7,6 +7,8 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"os/exec"
+	"path/filepath"
 
 	"github.com/eSlider/2dph/internal/brain/rank"
 )
@@ -19,8 +21,8 @@ func Ready() error {
 // HTTP is the in-process API used by bin/brain/serve.go.
 type HTTP struct{}
 
-func (HTTP) Search(ctx context.Context, query string, limit int) ([]byte, error) {
+func (HTTP) Search(ctx context.Context, query string, limit int, asOf string) ([]byte, error) {
-	hits, err := searchHits(query, "", "", limit)
+	hits, err := searchHits(query, "", "", limit, asOf)
 	if err != nil {
 		return nil, err
 	}
@@ -39,7 +41,7 @@ func (HTTP) Search(ctx context.Context, query string, limit int) ([]byte, error)
 	var buf bytes.Buffer
 	enc := json.NewEncoder(&buf)
 	enc.SetEscapeHTML(false)
-	if err := enc.Encode(toJSONOut(hits, query, "", webOut)); err != nil {
+	if err := enc.Encode(toJSONOut(hits, query, "", asOf, webOut)); err != nil {
 		return nil, err
 	}
 	return buf.Bytes(), nil
@@ -137,12 +139,22 @@ func (HTTP) Audit(context.Context) ([]byte, error) {
 	return json.Marshal(map[string]any{"status": "ok", "by_confidence": rows})
 }
 
-func (HTTP) Ingest(context.Context) ([]byte, error) {
+func (HTTP) Ingest(ctx context.Context, body []byte) ([]byte, error) {
+	if len(bytes.TrimSpace(body)) == 0 {
 		return json.Marshal(map[string]any{
-		"mode":    "rebuild",
+			"mode":    "add",
-		"command": "bin/brain/index.go --rebuild",
+			"command": "bin/brain/add.go",
-		"add":     "v2",
+			"rebuild": "bin/brain/index.go --rebuild",
 		})
+	}
+	cmd := exec.CommandContext(ctx, filepath.Join(repoRoot(), "bin", "kb", "add"), "--json")
+	cmd.Stdin = bytes.NewReader(body)
+	cmd.Dir = repoRoot()
+	out, err := cmd.Output()
+	if err != nil {
+		return nil, fmt.Errorf("add: %w", err)
+	}
+	return out, nil
 }
 
 func asInt(v any) int64 {

internal/brain/rank/args.go

@@ -3,73 +3,88 @@ package rank
 import (
 	"fmt"
 	"strconv"
-	"strings"
+
+	"github.com/eSlider/2dph/internal/cli"
+	"github.com/eSlider/2dph/internal/facts"
+	"github.com/integrii/flaggy"
 )
 
-const Usage = `usage: bin/brain/search.go "query" [--root facts|info] [--repo REPO] [-n N] [--json] [--no-web]
+const Usage = `usage: bin/brain/search.go "query" [--root facts|info] [--repo REPO] [-n N] [--hop N] [--as-of YYYY-MM-DD] [--json] [--no-web]
        bin/brain/search.go serve [port]
-       bin/brain/search.go --list-model`
+       bin/brain/search.go --list-model
+       source <(./bin/cli/complete.go bash)`
 
 type Options struct {
 	Query     string
 	Root      string
 	Repo      string
 	Limit     int
+	Hop       int
+	AsOf      string
 	JSONOut   bool
 	ListModel bool
 	NoWeb     bool
 }
 
+// NewParser is the flaggy schema for search (also used by bin/cli/complete.go).
+func NewParser(opt *Options) *flaggy.Parser {
+	if opt.Limit == 0 {
+		opt.Limit = 20
+	}
+	p := cli.New("brain-search")
+	p.Description = "deduction search: facts → info → web"
+	p.String(&opt.Root, "", "root", "facts or info")
+	p.String(&opt.Repo, "", "repo", "filter by repo")
+	p.Int(&opt.Limit, "n", "n", "max hits")
+	p.Int(&opt.Hop, "", "hop", "walk FROM_FILE depth 1-3")
+	p.String(&opt.AsOf, "", "as-of", "keep facts active on YYYY-MM-DD (D24)")
+	p.Bool(&opt.JSONOut, "", "json", "JSON output")
+	p.Bool(&opt.NoWeb, "", "no-web", "stay local")
+	p.Bool(&opt.ListModel, "", "list-model", "print embedding model")
+	return p
+}
+
 // ParseArgs reads flags. Unknown flags are an error: silently dropping them
 // meant `--hop 1` vanished and its argument `1` was appended to the query.
-// --hop is recognised so it cannot be swallowed; it is not implemented until
-// File/FROM_FILE edges exist.
 func ParseArgs(args []string) (Options, error) {
 	opt := Options{Limit: 20}
-	var queryArgs []string
+	p := NewParser(&opt)
-
+	var q string
-	for i := 0; i < len(args); i++ {
+	p.AddPositionalValue(&q, "query", 1, false, "search query")
-		arg := args[i]
+	if err := cli.Parse(p, args); err != nil {
-		wantsValue := arg == "--root" || arg == "--repo" || arg == "-n" || arg == "--hop"
+		return opt, err
-		if wantsValue && i+1 >= len(args) {
-			return opt, fmt.Errorf("%s needs a value", arg)
 	}
-		switch arg {
+	opt.Query = cli.Query(q, p.TrailingArguments)
-		case "--root":
+	if opt.Root != "" && opt.Root != "facts" && opt.Root != "info" {
-			i++
-			opt.Root = args[i]
-			if opt.Root != "facts" && opt.Root != "info" {
 		return opt, fmt.Errorf("--root must be facts or info, got %q", opt.Root)
 	}
-		case "--repo":
+	if opt.Limit < 1 {
-			i++
+		return opt, fmt.Errorf("-n must be a positive integer, got %q", strconv.Itoa(opt.Limit))
-			opt.Repo = args[i]
-		case "-n":
-			i++
-			n, err := strconv.Atoi(args[i])
-			if err != nil || n < 1 {
-				return opt, fmt.Errorf("-n must be a positive integer, got %q", args[i])
 	}
-			opt.Limit = n
+	if opt.Hop < 0 {
-		case "--hop":
+		return opt, fmt.Errorf("--hop must be a positive integer, got %q", strconv.Itoa(opt.Hop))
-			return opt, fmt.Errorf("--hop is not implemented yet (needs File/FROM_FILE edges)")
-		case "--json":
-			opt.JSONOut = true
-		case "--no-web":
-			opt.NoWeb = true
-		case "--list-model":
-			opt.ListModel = true
-		default:
-			if strings.HasPrefix(arg, "-") {
-				return opt, fmt.Errorf("unknown flag %q", arg)
 	}
-			queryArgs = append(queryArgs, arg)
+	if opt.Hop > 3 {
+		return opt, fmt.Errorf("--hop max is 3 (File → Commit → Person)")
 	}
+	if opt.AsOf != "" {
+		day := facts.NormalizeDay(opt.AsOf)
+		if len(day) != 10 || day[4] != '-' || day[7] != '-' {
+			return opt, fmt.Errorf("--as-of must be YYYY-MM-DD, got %q", opt.AsOf)
+		}
+		opt.AsOf = day
 	}
-
-	opt.Query = strings.TrimSpace(strings.Join(queryArgs, " "))
 	if opt.Query == "" && !opt.ListModel {
 		return opt, fmt.Errorf("no query given")
 	}
 	return opt, nil
 }
+
+// Parser is the search schema for bin/cli/complete.go.
+func Parser() *flaggy.Parser {
+	opt := Options{Limit: 20}
+	p := NewParser(&opt)
+	var q string
+	p.AddPositionalValue(&q, "query", 1, false, "search query")
+	return p
+}

internal/brain/rank/asof_test.go

@@ -0,0 +1,34 @@
+package rank
+
+import "testing"
+
+func TestFilterAsOfKeepsXDropsY(t *testing.T) {
+	hits := []Hit{
+		{ID: "x", Text: "Andrey works at X", ValidFrom: "2024-03-01", ValidTo: "2025-07-15"},
+		{ID: "y", Text: "Andrey works at Y", ValidFrom: "2025-07-16", ValidTo: ""},
+		{ID: "legacy", Text: "always true claim", ValidFrom: "", ValidTo: ""},
+	}
+	out := FilterAsOf(hits, "2025-01-01")
+	if len(out) != 2 {
+		t.Fatalf("len=%d want 2: %+v", len(out), out)
+	}
+	if out[0].ID != "x" || out[1].ID != "legacy" {
+		t.Fatalf("got %+v", out)
+	}
+	if FilterAsOf(hits, "") == nil || len(FilterAsOf(hits, "")) != 3 {
+		t.Fatal("empty as-of must keep all")
+	}
+}
+
+func TestParseArgsAsOf(t *testing.T) {
+	opt, err := ParseArgs([]string{"who works where", "--as-of", "2025-01-01", "--json"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if opt.AsOf != "2025-01-01" {
+		t.Fatalf("AsOf=%q", opt.AsOf)
+	}
+	if _, err := ParseArgs([]string{"q", "--as-of", "not-a-date"}); err == nil {
+		t.Fatal("expected bad as-of error")
+	}
+}

internal/brain/rank/escalate.go

@@ -19,20 +19,35 @@ type SecondSourceHit struct {
 
 type WebFn func(query string) SecondSource
 
-// ShouldEscalate is true when the default deduction path has no facts hit.
+// ShouldEscalate is true when the default deduction path has no confirmed
+// facts hit. Hypothesis/partial facts are `(not confirmed)` (D16).
 // `--root facts|info` is a single-root ask: do not mix in the web.
 func ShouldEscalate(hits []Hit, rootFilter string) bool {
 	if rootFilter != "" {
 		return false
 	}
 	for _, h := range hits {
-		if h.Root == "facts" {
+		if ConfirmedFact(h) {
 			return false
 		}
 	}
 	return true
 }
 
+// ConfirmedFact is a facts-root hit that is not hypothesis/partial.
+// Empty confidence is treated as confirmed (legacy leafs).
+func ConfirmedFact(h Hit) bool {
+	if h.Root != "facts" {
+		return false
+	}
+	switch h.Confidence {
+	case "hypothesis", "partial":
+		return false
+	default:
+		return true
+	}
+}
+
 // Deduce returns the second-source block, or nil when web must not run.
 func Deduce(hits []Hit, query, rootFilter string, noWeb bool, web WebFn) *SecondSource {
 	if noWeb || web == nil || !ShouldEscalate(hits, rootFilter) {

internal/brain/rank/escalate_test.go

@@ -14,6 +14,16 @@ func TestShouldEscalateWhenNoFacts(t *testing.T) {
 	}
 }
 
+func TestShouldEscalateWhenHypothesisFacts(t *testing.T) {
+	hyp := Hit{ID: "c", Root: "facts", Confidence: "hypothesis", Source: "a x b vs c x d"}
+	if !ShouldEscalate([]Hit{hyp}, "") {
+		t.Fatal("hypothesis facts are (not confirmed); escalate")
+	}
+	if ConfirmedFact(hyp) {
+		t.Fatal("hypothesis is not confirmed")
+	}
+}
+
 func TestShouldNotEscalateWhenFactsConfirm(t *testing.T) {
 	hits := []Hit{h("f", "facts", "docker ps x compose"), h("i", "info", "docs/a.md")}
 	if ShouldEscalate(hits, "") {

internal/brain/rank/query.go

@@ -3,7 +3,36 @@ package rank
 // BM25 ranks best-first, so the top hits are the *highest* scores; cosine
 // distance ranks best-first ascending. Both mirror kblib.py.
 const FTSStmt = "CALL QUERY_FTS_INDEX('Leaf', 'id', $q) " +
-	"RETURN node.id, node.text, node.root, node.source, score ORDER BY score DESC LIMIT $n"
+	"RETURN node.id, node.text, node.root, node.source, score, node.confidence, " +
+	"node.valid_from, node.valid_to ORDER BY score DESC LIMIT $n"
 
 const VecStmt = "CALL QUERY_VECTOR_INDEX('Leaf', 'Leaf_vec', $q, $n) " +
-	"RETURN node.id, node.text, node.root, node.source, distance ORDER BY distance LIMIT $n"
+	"RETURN node.id, node.text, node.root, node.source, distance, node.confidence, " +
+	"node.valid_from, node.valid_to ORDER BY distance LIMIT $n"
+
+// HopStmt is the Cypher walk from a search hit. Depth 1 = File, 2 = Commit, 3 = Person.
+func HopStmt(depth int) string {
+	switch depth {
+	case 1:
+		return "MATCH (l:Leaf {id:$id})-[:FROM_FILE]->(f:File) RETURN f.id, f.path, 1"
+	case 2:
+		return "MATCH (l:Leaf {id:$id})-[:FROM_FILE]->(f:File)-[:HAS_VERSION]->(c:Commit) RETURN c.id, c.subject, 2"
+	case 3:
+		return "MATCH (l:Leaf {id:$id})-[:FROM_FILE]->(f:File)-[:HAS_VERSION]->(c:Commit)-[:AUTHORED]->(p:Person) RETURN p.id, p.name, 3"
+	default:
+		return ""
+	}
+}
+
+func HopLabel(depth int) string {
+	switch depth {
+	case 1:
+		return "File"
+	case 2:
+		return "Commit"
+	case 3:
+		return "Person"
+	default:
+		return ""
+	}
+}

internal/brain/rank/rank.go

@@ -5,26 +5,44 @@ package rank
 import (
 	"sort"
 	"strings"
+
+	"github.com/eSlider/2dph/internal/facts"
 )
 
+type HopNode struct {
+	ID    string `json:"id"`
+	Label string `json:"label"`
+	Name  string `json:"name"`
+	Depth int    `json:"depth"`
+}
+
 // Hit is one search result, mirroring the python script's dict shape.
 type Hit struct {
 	ID         string    `json:"id"`
 	Text       string    `json:"text"`
 	Root       string    `json:"root"`
+	Confidence string    `json:"confidence,omitempty"`
 	Source     string    `json:"-"`
 	Score      float64   `json:"score"`
 	Snippet    string    `json:"snippet,omitempty"`
+	ValidFrom  string    `json:"valid_from,omitempty"`
+	ValidTo    string    `json:"valid_to,omitempty"`
+	Hops       []HopNode `json:"hops,omitempty"`
 }
 
 // rrfK dampens the contribution of low ranks; same constant as kblib.py.
 const rrfK = 60
 
-// RankAndFilter fuses the two hit lists, applies --root/--repo, then cuts to
+// RankAndFilter fuses the two hit lists, applies --root/--repo/--as-of, then
-// limit. Cutting first dropped every matching leaf ranked below the cut, so
+// cuts to limit. Cutting first dropped every matching leaf ranked below the
-// `--root facts` came back empty whenever info leafs filled the top N.
+// cut, so `--root facts` came back empty whenever info leafs filled the top N.
-// limit <= 0 keeps everything.
+// limit <= 0 keeps everything. asOf empty skips interval filter (D24).
 func RankAndFilter(fts, vec []Hit, root, repo string, limit int) []Hit {
+	return RankAndFilterAsOf(fts, vec, root, repo, "", limit)
+}
+
+// RankAndFilterAsOf is RankAndFilter with D24 fact-interval filter.
+func RankAndFilterAsOf(fts, vec []Hit, root, repo, asOf string, limit int) []Hit {
 	out := Hybrid(fts, vec, 0)
 	if root != "" {
 		out = FilterRoot(out, root)
@@ -32,12 +50,30 @@ func RankAndFilter(fts, vec []Hit, root, repo string, limit int) []Hit {
 	if repo != "" {
 		out = FilterRepo(out, repo)
 	}
+	if asOf != "" {
+		out = FilterAsOf(out, asOf)
+	}
 	if limit > 0 && len(out) > limit {
 		out = out[:limit]
 	}
 	return out
 }
 
+// FilterAsOf keeps hits whose [valid_from, valid_to] covers asOf (D24).
+// Empty intervals stay (legacy leafs). Empty asOf keeps all.
+func FilterAsOf(hits []Hit, asOf string) []Hit {
+	if asOf == "" {
+		return hits
+	}
+	var out []Hit
+	for _, h := range hits {
+		if facts.ActiveAt(h.ValidFrom, h.ValidTo, asOf) {
+			out = append(out, h)
+		}
+	}
+	return out
+}
+
 // Hybrid merges FTS and vector hits by reciprocal rank fusion.
 // limit <= 0 returns the full fused list.
 func Hybrid(fts, vec []Hit, limit int) []Hit {

internal/brain/rank/rank_test.go

@@ -91,15 +91,41 @@ func TestHybridKeepsVectorScoreForSharedHit(t *testing.T) {
 }
 
 // The old parser dropped unknown flags and appended their arguments to the
-// query, so `search "q" --hop 1` searched for "q 1". --hop is not implemented
+// query, so `search "q" --hop 1` searched for "q 1". --hop must stay a flag.
-// here (needs File edges); it must still fail closed instead of changing q.
 func TestParseHopIsNotSwallowedIntoTheQuery(t *testing.T) {
-	_, err := ParseArgs([]string{"what runs on arc-2", "--hop", "1"})
+	opt, err := ParseArgs([]string{"what runs on arc-2", "--hop", "1"})
-	if err == nil {
+	if err != nil {
-		t.Fatal("expected --hop to error (not implemented), not be swallowed")
+		t.Fatalf("unexpected error: %v", err)
 	}
-	if !strings.Contains(err.Error(), "--hop") {
+	if opt.Query != "what runs on arc-2" {
-		t.Fatalf("error should name --hop, got %v", err)
+		t.Fatalf("query swallowed hop arg: %q", opt.Query)
+	}
+	if opt.Hop != 1 {
+		t.Fatalf("hop = %d, want 1", opt.Hop)
+	}
+}
+
+func TestParseHopMaxIsThree(t *testing.T) {
+	if _, err := ParseArgs([]string{"q", "--hop", "4"}); err == nil {
+		t.Fatal("expected --hop 4 to error")
+	}
+	opt, err := ParseArgs([]string{"q", "--hop", "3"})
+	if err != nil || opt.Hop != 3 {
+		t.Fatalf("hop 3: %+v err=%v", opt, err)
+	}
+}
+
+func TestHopStmtWalksFromFile(t *testing.T) {
+	s := HopStmt(1)
+	if !strings.Contains(s, "FROM_FILE") || !strings.Contains(s, "File") {
+		t.Fatalf("hop 1 must walk FROM_FILE, got %q", s)
+	}
+	s3 := HopStmt(3)
+	if !strings.Contains(s3, "HAS_VERSION") || !strings.Contains(s3, "AUTHORED") || !strings.Contains(s3, "Person") {
+		t.Fatalf("hop 3 must reach Person, got %q", s3)
+	}
+	if HopLabel(1) != "File" || HopLabel(3) != "Person" {
+		t.Fatal("hop labels")
 	}
 }
 
@@ -146,4 +172,7 @@ func TestFTSQueryOrdersByScoreDescending(t *testing.T) {
 	if !strings.Contains(FTSStmt, "ORDER BY score DESC") {
 		t.Fatalf("FTS query must order by score DESC, got:\n%s", FTSStmt)
 	}
+	if !strings.Contains(FTSStmt, "node.confidence") {
+		t.Fatal("FTS must return confidence for D16")
+	}
 }

internal/brain/rank/readargs.go

@@ -0,0 +1,59 @@
+package rank
+
+import (
+	"fmt"
+
+	"github.com/eSlider/2dph/internal/cli"
+	"github.com/integrii/flaggy"
+)
+
+type GetOptions struct {
+	ID      string
+	Body    bool
+	JSONOut bool
+}
+
+func GetParser(opt *GetOptions) *flaggy.Parser {
+	p := cli.New("brain-get")
+	p.Description = "read one leaf"
+	p.Bool(&opt.Body, "", "body", "full text instead of snippet")
+	p.Bool(&opt.JSONOut, "", "json", "JSON output")
+	p.AddPositionalValue(&opt.ID, "id", 1, false, "leaf id")
+	return p
+}
+
+func ParseGet(args []string) (GetOptions, error) {
+	var opt GetOptions
+	if err := cli.Parse(GetParser(&opt), args); err != nil {
+		return opt, err
+	}
+	if opt.ID == "" {
+		return opt, fmt.Errorf("id required")
+	}
+	return opt, nil
+}
+
+type JSONFlag struct {
+	JSONOut bool
+}
+
+func bindJSON(name string, opt *JSONFlag) *flaggy.Parser {
+	p := cli.New(name)
+	p.Bool(&opt.JSONOut, "", "json", "JSON output")
+	return p
+}
+
+func StatsParser() *flaggy.Parser {
+	opt := JSONFlag{}
+	return bindJSON("brain-stats", &opt)
+}
+
+func EvalParser() *flaggy.Parser {
+	opt := JSONFlag{}
+	return bindJSON("brain-eval", &opt)
+}
+
+func ParseJSONFlag(name string, args []string) (JSONFlag, error) {
+	var opt JSONFlag
+	return opt, cli.Parse(bindJSON(name, &opt), args)
+}

internal/brain/read.go

@@ -11,30 +11,15 @@ import (
 	"unicode/utf8"
 
 	"github.com/eSlider/2dph/internal/brain/rank"
+	"github.com/eSlider/2dph/internal/cli"
 )
 
 func MainGet(args []string) int {
-	id, body, jsonOut := "", false, false
+	opt, err := rank.ParseGet(args)
-	for _, a := range args {
+	if err != nil {
-		switch {
+		return cli.Fail(err)
-		case a == "--body":
-			body = true
-		case a == "--json":
-			jsonOut = true
-		case a == "-h" || a == "--help":
-			fmt.Fprintln(os.Stderr, `usage: bin/brain/get.go <id> [--body] [--json]`)
-			return 0
-		case strings.HasPrefix(a, "-"):
-			fmt.Fprintf(os.Stderr, "brain/get: unknown flag %s\n", a)
-			return 2
-		default:
-			id = a
-		}
-	}
-	if id == "" {
-		fmt.Fprintln(os.Stderr, "brain/get: id required")
-		return 2
 	}
+	id, body, jsonOut := opt.ID, opt.Body, opt.JSONOut
 	if err := openBrain(); err != nil {
 		fmt.Fprintf(os.Stderr, "open brain: %v\n", err)
 		return 1
@@ -72,21 +57,11 @@ func MainGet(args []string) int {
 }
 
 func MainStats(args []string) int {
-	jsonOut := false
+	opt, err := rank.ParseJSONFlag("brain-stats", args)
-	for _, a := range args {
+	if err != nil {
-		switch a {
+		return cli.Fail(err)
-		case "--json":
-			jsonOut = true
-		case "-h", "--help":
-			fmt.Fprintln(os.Stderr, `usage: bin/brain/stats.go [--json]`)
-			return 0
-		default:
-			if strings.HasPrefix(a, "-") {
-				fmt.Fprintf(os.Stderr, "brain/stats: unknown flag %s\n", a)
-				return 2
-			}
-		}
 	}
+	jsonOut := opt.JSONOut
 	if err := openBrain(); err != nil {
 		fmt.Fprintf(os.Stderr, "open brain: %v\n", err)
 		return 1
@@ -124,21 +99,11 @@ func MainStats(args []string) int {
 }
 
 func MainEval(args []string) int {
-	jsonOut := false
+	opt, err := rank.ParseJSONFlag("brain-eval", args)
-	for _, a := range args {
+	if err != nil {
-		switch a {
+		return cli.Fail(err)
-		case "--json":
-			jsonOut = true
-		case "-h", "--help":
-			fmt.Fprintln(os.Stderr, `usage: bin/brain/eval.go [--json]`)
-			return 0
-		default:
-			if strings.HasPrefix(a, "-") {
-				fmt.Fprintf(os.Stderr, "brain/eval: unknown flag %s\n", a)
-				return 2
-			}
-		}
 	}
+	jsonOut := opt.JSONOut
 	if err := openBrain(); err != nil {
 		fmt.Fprintf(os.Stderr, "open brain: %v\n", err)
 		return 1

internal/brain/search.go

@@ -20,6 +20,7 @@ import (
 
 	lbug "github.com/LadybugDB/go-ladybug"
 	"github.com/eSlider/2dph/internal/brain/rank"
+	"github.com/eSlider/2dph/internal/cli"
 )
 
 const defaultPort = 17830
@@ -29,6 +30,9 @@ const healthPath = "/health"
 func runSearch(args []string) int {
 	opt, err := rank.ParseArgs(args)
 	if err != nil {
+		if errors.Is(err, cli.ErrHelp) {
+			return 0
+		}
 		fmt.Fprintf(os.Stderr, "brain/search: %v\n%s\n", err, rank.Usage)
 		return 2
 	}
@@ -51,11 +55,17 @@ func runSearch(args []string) int {
 	}
 	defer closeBrain()
 
-	hits, err := searchHits(query, root, repo, limit)
+	hits, err := searchHits(query, root, repo, limit, opt.AsOf)
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "search: %v\n", err)
 		return 1
 	}
+	if opt.Hop > 0 {
+		if err := attachHops(hits, opt.Hop); err != nil {
+			fmt.Fprintf(os.Stderr, "hop: %v\n", err)
+			return 1
+		}
+	}
 
 	results := hits
 	for i := range results {
@@ -75,6 +85,7 @@ func runSearch(args []string) int {
 	out := Dict{
 		{"query", query},
 		{"root_filter", root},
+		{"as_of", opt.AsOf},
 		{"count", len(results)},
 		{"results", resultsToDicts(results)},
 	}
@@ -86,13 +97,13 @@ func runSearch(args []string) int {
 		enc := json.NewEncoder(os.Stdout)
 		enc.SetIndent("", "  ")
 		enc.SetEscapeHTML(false)
-		return b2i(enc.Encode(toJSONOut(results, query, root, webOut)))
+		return b2i(enc.Encode(toJSONOut(results, query, root, opt.AsOf, webOut)))
 	}
 	fmt.Print(toYAML(out, 0))
 	return 0
 }
 
-func searchHits(query, root, repo string, limit int) ([]Hit, error) {
+func searchHits(query, root, repo string, limit int, asOf string) ([]Hit, error) {
 	emb, err := embedQuery(query)
 	if err != nil {
 		return nil, fmt.Errorf("embed: %w", err)
@@ -105,7 +116,45 @@ func searchHits(query, root, repo string, limit int) ([]Hit, error) {
 	if vec, err = queryVector(emb, limit*3); err != nil {
 		fmt.Fprintf(os.Stderr, "vec: %v\n", err)
 	}
-	return rank.RankAndFilter(fts, vec, root, repo, limit), nil
+	return rank.RankAndFilterAsOf(fts, vec, root, repo, asOf, limit), nil
+}
+
+func attachHops(hits []Hit, n int) error {
+	if conn == nil {
+		return fmt.Errorf("brain not open")
+	}
+	for i := range hits {
+		var hops []rank.HopNode
+		for d := 1; d <= n; d++ {
+			stmt, err := conn.Prepare(rank.HopStmt(d))
+			if err != nil {
+				return err
+			}
+			res, err := conn.Execute(stmt, map[string]any{"id": hits[i].ID})
+			stmt.Close()
+			if err != nil {
+				return err
+			}
+			for res.HasNext() {
+				row, err := res.Next()
+				if err != nil {
+					return err
+				}
+				vals, err := row.GetAsSlice()
+				if err != nil || len(vals) < 3 {
+					continue
+				}
+				hops = append(hops, rank.HopNode{
+					ID:    fmt.Sprint(vals[0]),
+					Label: rank.HopLabel(d),
+					Name:  fmt.Sprint(vals[1]),
+					Depth: int(asInt(vals[2])),
+				})
+			}
+		}
+		hits[i].Hops = hops
+	}
+	return nil
 }
 
 func b2i(err error) int {
@@ -168,15 +217,39 @@ func rowsToHits(res *lbug.QueryResult) ([]Hit, error) {
 		root := fmt.Sprint(vals[2])
 		source := fmt.Sprint(vals[3])
 		score := float64(vals[4].(float64))
-		hits = append(hits, Hit{ID: id, Text: text, Root: root, Source: source, Score: score})
+		conf := ""
+		if len(vals) >= 6 {
+			conf = fmt.Sprint(vals[5])
+		}
+		vf, vt := "", ""
+		if len(vals) >= 8 {
+			vf = nullStr(vals[6])
+			vt = nullStr(vals[7])
+		}
+		hits = append(hits, Hit{
+			ID: id, Text: text, Root: root, Source: source, Score: score,
+			Confidence: conf, ValidFrom: vf, ValidTo: vt,
+		})
 	}
 	return hits, nil
 }
 
+func nullStr(v any) string {
+	if v == nil {
+		return ""
+	}
+	s := fmt.Sprint(v)
+	if s == "<nil>" {
+		return ""
+	}
+	return s
+}
+
 // JSON output types
 type jsonOut struct {
 	Query      string             `json:"query"`
 	RootFilter string             `json:"root_filter"`
+	AsOf       string             `json:"as_of,omitempty"`
 	Count      int                `json:"count"`
 	Results    []jsonHit          `json:"results"`
 	Web        *rank.SecondSource `json:"web,omitempty"`
@@ -186,24 +259,33 @@ type jsonHit struct {
 	ID         string         `json:"id"`
 	Text       string         `json:"text"`
 	Root       string         `json:"root"`
+	Confidence string         `json:"confidence,omitempty"`
 	Score      float64        `json:"score"`
 	Snippet    string         `json:"snippet,omitempty"`
+	ValidFrom  string         `json:"valid_from,omitempty"`
+	ValidTo    string         `json:"valid_to,omitempty"`
+	Hops       []rank.HopNode `json:"hops,omitempty"`
 }
 
-func toJSONOut(hits []Hit, query, rootFilter string, web *rank.SecondSource) *jsonOut {
+func toJSONOut(hits []Hit, query, rootFilter, asOf string, web *rank.SecondSource) *jsonOut {
 	out := make([]jsonHit, len(hits))
 	for i, h := range hits {
 		out[i] = jsonHit{
 			ID:         h.ID,
 			Text:       h.Text,
 			Root:       h.Root,
+			Confidence: h.Confidence,
 			Score:      h.Score,
 			Snippet:    h.Snippet,
+			ValidFrom:  h.ValidFrom,
+			ValidTo:    h.ValidTo,
+			Hops:       h.Hops,
 		}
 	}
 	return &jsonOut{
 		Query:      query,
 		RootFilter: rootFilter,
+		AsOf:       asOf,
 		Count:      len(hits),
 		Results:    out,
 		Web:        web,
@@ -219,9 +301,30 @@ func resultsToDicts(hits []Hit) []any {
 			{"root", h.Root},
 			{"score", h.Score},
 		}
+		if h.Confidence != "" {
+			d = append(d, KV{"confidence", h.Confidence})
+		}
+		if h.ValidFrom != "" {
+			d = append(d, KV{"valid_from", h.ValidFrom})
+		}
+		if h.ValidTo != "" {
+			d = append(d, KV{"valid_to", h.ValidTo})
+		}
 		if h.Snippet != "" {
 			d = append(d, KV{"snippet", h.Snippet})
 		}
+		if len(h.Hops) > 0 {
+			nodes := make([]any, len(h.Hops))
+			for j, n := range h.Hops {
+				nodes[j] = Dict{
+					{"id", n.ID},
+					{"label", n.Label},
+					{"name", n.Name},
+					{"depth", n.Depth},
+				}
+			}
+			d = append(d, KV{"hops", nodes})
+		}
 		out[i] = d
 	}
 	return out

internal/chats/apply.go

@@ -3,12 +3,13 @@ package chats
 import (
 	"bytes"
 	"encoding/json"
-	"flag"
 	"fmt"
 	"os"
 	"os/exec"
 	"path/filepath"
 	"strings"
+
+	cliparse "github.com/eSlider/2dph/internal/cli"
 )
 
 type ooContact struct {
@@ -25,16 +26,9 @@ type ooContact struct {
 }
 
 func RunApply(args []string) int {
-	fs := flag.NewFlagSet("chats apply", flag.ContinueOnError)
+	dryRun, err := parseApplyFlags(args)
-	dryRun := fs.Bool("dry-run", false, "show what would be done without writing")
+	if err != nil {
-	help := fs.Bool("help", false, "")
+		return cliparse.Fail(err)
-	fs.SetOutput(os.Stderr)
-	if err := fs.Parse(args); err != nil {
-		return 2
-	}
-	if *help {
-		fmt.Fprintln(os.Stderr, "usage: chats apply [--dry-run]")
-		return 0
 	}
 
 	ooCLI := findOO()
@@ -128,7 +122,7 @@ func RunApply(args []string) int {
 
 	fmt.Printf("\nchats apply: %d actions to apply\n", len(resolved))
 
-	if *dryRun {
+	if dryRun {
 		for _, r := range resolved {
 			switch r.Action {
 			case "info-add":

internal/chats/cli.go

@@ -0,0 +1,74 @@
+package chats
+
+import (
+	cliparse "github.com/eSlider/2dph/internal/cli"
+	"github.com/integrii/flaggy"
+)
+
+type syncTelegramFlags struct {
+	Limit int
+	Phone string
+}
+
+type syncLinkedInFlags struct {
+	Limit   int
+	Refresh bool
+}
+
+func SyncParser() *flaggy.Parser {
+	p := cliparse.New("chats-sync")
+	p.Description = "download chats to var/chats"
+	tg := flaggy.NewSubcommand("telegram")
+	li := flaggy.NewSubcommand("linkedin")
+	var limit int
+	var phone string
+	var refresh bool
+	tg.Int(&limit, "", "limit", "max messages per chat")
+	tg.String(&phone, "", "phone", "phone (default TELEGRAM_PHONE)")
+	li.Int(&limit, "", "limit", "max messages per conversation")
+	li.Bool(&refresh, "", "refresh", "refresh webtop session")
+	p.AttachSubcommand(tg, 1)
+	p.AttachSubcommand(li, 1)
+	return p
+}
+
+func ImportParser() *flaggy.Parser {
+	return cliparse.New("chats-import")
+}
+
+func FactsParser() *flaggy.Parser {
+	return cliparse.New("chats-facts")
+}
+
+func ApplyParser() *flaggy.Parser {
+	p := cliparse.New("chats-apply")
+	dry := false
+	p.Bool(&dry, "", "dry-run", "show without writing")
+	return p
+}
+
+func parseTelegramFlags(args []string) (syncTelegramFlags, error) {
+	var f syncTelegramFlags
+	p := cliparse.New("chats-sync-telegram")
+	p.Int(&f.Limit, "", "limit", "max messages per chat")
+	p.String(&f.Phone, "", "phone", "phone (default TELEGRAM_PHONE)")
+	return f, cliparse.Parse(p, args)
+}
+
+func parseLinkedInFlags(args []string) (syncLinkedInFlags, error) {
+	var f syncLinkedInFlags
+	p := cliparse.New("chats-sync-linkedin")
+	p.Int(&f.Limit, "", "limit", "max messages per conversation")
+	p.Bool(&f.Refresh, "", "refresh", "refresh webtop session")
+	return f, cliparse.Parse(p, args)
+}
+
+func parseApplyFlags(args []string) (dryRun bool, err error) {
+	p := cliparse.New("chats-apply")
+	p.Bool(&dryRun, "", "dry-run", "show without writing")
+	return dryRun, cliparse.Parse(p, args)
+}
+
+func parseNoFlags(name string, args []string) error {
+	return cliparse.Parse(cliparse.New(name), args)
+}

internal/chats/facts.go

@@ -3,12 +3,13 @@ package chats
 import (
 	"bufio"
 	"encoding/json"
-	"flag"
 	"fmt"
 	"os"
 	"path/filepath"
 	"regexp"
 	"strings"
+
+	cliparse "github.com/eSlider/2dph/internal/cli"
 )
 
 var (
@@ -76,15 +77,8 @@ type ExtractedFact struct {
 }
 
 func RunFacts(args []string) int {
-	fs := flag.NewFlagSet("chats facts", flag.ContinueOnError)
+	if err := parseNoFlags("chats-facts", args); err != nil {
-	help := fs.Bool("help", false, "")
+		return cliparse.Fail(err)
-	fs.SetOutput(os.Stderr)
-	if err := fs.Parse(args); err != nil {
-		return 2
-	}
-	if *help {
-		fmt.Fprintln(os.Stderr, "usage: chats facts")
-		return 0
 	}
 
 	root := Dir()

internal/chats/import.go

@@ -4,25 +4,19 @@ import (
 	"bufio"
 	"bytes"
 	"encoding/json"
-	"flag"
 	"fmt"
 	"html"
 	"os"
 	"path/filepath"
 	"sort"
 	"strings"
+
+	cliparse "github.com/eSlider/2dph/internal/cli"
 )
 
 func RunImport(args []string) int {
-	fs := flag.NewFlagSet("chats import", flag.ContinueOnError)
+	if err := parseNoFlags("chats-import", args); err != nil {
-	help := fs.Bool("help", false, "")
+		return cliparse.Fail(err)
-	fs.SetOutput(os.Stderr)
-	if err := fs.Parse(args); err != nil {
-		return 2
-	}
-	if *help {
-		fmt.Fprintln(os.Stderr, "usage: chats import")
-		return 0
 	}
 
 	root := Dir()

internal/chats/sync_linkedin.go

@@ -2,12 +2,13 @@ package chats
 
 import (
 	"context"
-	"flag"
 	"fmt"
 	"os"
 	"os/exec"
 	"path/filepath"
 	"time"
+
+	cliparse "github.com/eSlider/2dph/internal/cli"
 )
 
 func checkLinkedInSession(userDataDir string) (bool, error) {
@@ -29,18 +30,12 @@ func checkLinkedInSession(userDataDir string) (bool, error) {
 }
 
 func RunSyncLinkedIn(args []string) int {
-	fs := flag.NewFlagSet("chats sync linkedin", flag.ContinueOnError)
+	f, err := parseLinkedInFlags(args)
-	limit := fs.Int("limit", 0, "max messages per conversation (0 = all)")
+	if err != nil {
-	refresh := fs.Bool("refresh", false, "refresh session from live webtop browser before sync")
+		return cliparse.Fail(err)
-	help := fs.Bool("help", false, "")
-	fs.SetOutput(os.Stderr)
-	if err := fs.Parse(args); err != nil {
-		return 2
-	}
-	if *help {
-		fmt.Fprintln(os.Stderr, "usage: chats sync linkedin [--limit N] [--refresh]")
-		return 0
 	}
+	limit := f.Limit
+	refresh := f.Refresh
 
 	userDataDir := envVar("LINKEDIN_USER_DATA_DIR", "")
 	if userDataDir == "" {
@@ -48,7 +43,7 @@ func RunSyncLinkedIn(args []string) int {
 		userDataDir = home + "/.linkedin-mcp/profile"
 	}
 
-	if *refresh {
+	if refresh {
 		if code := refreshLinkedInSession(userDataDir); code != 0 {
 			return code
 		}
@@ -72,7 +67,7 @@ func RunSyncLinkedIn(args []string) int {
 	defer cancel()
 
 	start := time.Now()
-	if err := src.Sync(ctx, Dir(), *limit); err != nil {
+	if err := src.Sync(ctx, Dir(), limit); err != nil {
 		fmt.Fprintf(os.Stderr, "chats sync linkedin: %v\n", err)
 		return 1
 	}

internal/chats/sync_telegram.go

@@ -2,33 +2,28 @@ package chats
 
 import (
 	"context"
-	"flag"
 	"fmt"
 	"os"
 	"path/filepath"
 	"strconv"
 	"strings"
 	"time"
+
+	cliparse "github.com/eSlider/2dph/internal/cli"
 )
 
 func RunSyncTelegram(args []string) int {
-	fs := flag.NewFlagSet("chats sync telegram", flag.ContinueOnError)
+	f, err := parseTelegramFlags(args)
-	limit := fs.Int("limit", 0, "max messages per chat (0 = all)")
+	if err != nil {
-	phone := fs.String("phone", "", "phone number (default env TELEGRAM_PHONE)")
+		return cliparse.Fail(err)
-	help := fs.Bool("help", false, "")
-	fs.SetOutput(os.Stderr)
-	if err := fs.Parse(args); err != nil {
-		return 2
-	}
-	if *help {
-		fmt.Fprintln(os.Stderr, "usage: chats sync telegram [--limit N] [--phone PHONE]")
-		return 0
 	}
+	limit := f.Limit
+	phone := f.Phone
 
 	apiIDStr := envVar("TELEGRAM_API_ID", "")
 	apiHash := envVar("TELEGRAM_API_HASH", "")
 	sessionStr := envVar("TELEGRAM_SESSION_STRING", "")
-	phoneNum := *phone
+	phoneNum := phone
 	if phoneNum == "" {
 		phoneNum = envVar("TELEGRAM_PHONE", "")
 	}
@@ -78,7 +73,7 @@ func RunSyncTelegram(args []string) int {
 	defer cancel()
 
 	start := time.Now()
-	if err := src.Sync(ctx, Dir(), *limit); err != nil {
+	if err := src.Sync(ctx, Dir(), limit); err != nil {
 		fmt.Fprintf(os.Stderr, "chats sync telegram: %v\n", err)
 		return 1
 	}

internal/cli/cli.go

@@ -0,0 +1,190 @@
+// Package cli is the shared flaggy wrapper (D23).
+//
+// flaggy: zero deps, flags at any position, shell completion scripts.
+// Individual tools keep ShowCompletion off so a query like "completion" is
+// not stolen; dump scripts with bin/cli/complete.go.
+package cli
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"strings"
+	"sync"
+
+	"github.com/integrii/flaggy"
+)
+
+// ErrHelp means -h/--help was requested (exit 0).
+var ErrHelp = errors.New("help")
+
+var parseMu sync.Mutex
+
+// New returns a per-call parser. Never reuse: flaggy parses once.
+func New(name string) *flaggy.Parser {
+	p := flaggy.NewParser(name)
+	p.ShowVersionWithVersionFlag = false
+	p.ShowCompletion = false
+	// Extra positionals become TrailingArguments (search "two words --json").
+	// Unknown dash tokens are rejected in Parse after flaggy returns.
+	p.ShowHelpOnUnexpected = false
+	p.ShowHelpWithHFlag = true
+	return p
+}
+
+// Parse runs p.ParseArgs and turns flaggy's os.Exit into an error.
+// Not safe to call in parallel (flaggy.PanicInsteadOfExit is process-global).
+func Parse(p *flaggy.Parser, args []string) error {
+	parseMu.Lock()
+	defer parseMu.Unlock()
+	prev := flaggy.PanicInsteadOfExit
+	flaggy.PanicInsteadOfExit = true
+	defer func() { flaggy.PanicInsteadOfExit = prev }()
+
+	var exitMsg string
+	err := func() error {
+		defer func() {
+			if r := recover(); r != nil {
+				exitMsg = fmt.Sprint(r)
+			}
+		}()
+		return p.ParseArgs(args)
+	}()
+	if err != nil {
+		return err
+	}
+	if exitMsg != "" {
+		if strings.Contains(exitMsg, "code: 0") {
+			return ErrHelp
+		}
+		return errors.New(exitMsg)
+	}
+	if u := unknownFlags(p, args); len(u) > 0 {
+		return fmt.Errorf("unknown flag %q", u[0])
+	}
+	return nil
+}
+
+func unknownFlags(p *flaggy.Parser, args []string) []string {
+	flags := collectFlags(&p.Subcommand)
+	var out []string
+	skipNext := false
+	for _, a := range args {
+		if skipNext {
+			skipNext = false
+			continue
+		}
+		if a == "--" {
+			break
+		}
+		name, inline := flagName(a)
+		if name == "" {
+			continue
+		}
+		if name == "h" || name == "help" {
+			continue
+		}
+		f := findFlag(flags, name)
+		if f == nil {
+			out = append(out, a)
+			continue
+		}
+		if !inline && !isBoolFlag(f) {
+			skipNext = true
+		}
+	}
+	return out
+}
+
+func flagName(a string) (name string, inline bool) {
+	if a == "-" || !strings.HasPrefix(a, "-") {
+		return "", false
+	}
+	rest := strings.TrimLeft(a, "-")
+	name, _, inline = strings.Cut(rest, "=")
+	return name, inline
+}
+
+func collectFlags(sc *flaggy.Subcommand) []*flaggy.Flag {
+	out := append([]*flaggy.Flag{}, sc.Flags...)
+	for _, sub := range sc.Subcommands {
+		out = append(out, collectFlags(sub)...)
+	}
+	return out
+}
+
+func findFlag(flags []*flaggy.Flag, name string) *flaggy.Flag {
+	for _, f := range flags {
+		if f.HasName(name) {
+			return f
+		}
+	}
+	return nil
+}
+
+func isBoolFlag(f *flaggy.Flag) bool {
+	_, ok := f.AssignmentVar.(*bool)
+	return ok
+}
+
+// Query joins the first positional with leftover trailing words.
+func Query(first string, trailing []string) string {
+	parts := make([]string, 0, 1+len(trailing))
+	if s := strings.TrimSpace(first); s != "" {
+		parts = append(parts, s)
+	}
+	for _, t := range trailing {
+		if s := strings.TrimSpace(t); s != "" {
+			parts = append(parts, s)
+		}
+	}
+	return strings.Join(parts, " ")
+}
+
+// Code maps parse errors to process exit codes (0 help, 2 usage).
+func Code(err error) int {
+	if err == nil || errors.Is(err, ErrHelp) {
+		return 0
+	}
+	return 2
+}
+
+// Fail prints err unless it is help or a flaggy exit that already wrote stderr.
+func Fail(err error) int {
+	if err == nil || errors.Is(err, ErrHelp) {
+		return 0
+	}
+	if strings.HasPrefix(err.Error(), "Panic instead of exit") {
+		return 2
+	}
+	fmt.Fprintln(os.Stderr, err)
+	return 2
+}
+
+// Tool is one shebang CLI for completion dump.
+type Tool struct {
+	Path string
+	Name string
+	New  func() *flaggy.Parser
+}
+
+// BashScript concatenates flaggy bash complete scripts and binds each
+// function to the shebang path (./bin/subject/method.go).
+func BashScript(tools []Tool) string {
+	var b strings.Builder
+	b.WriteString("# 2dph flaggy completions (D23). source <(./bin/cli/complete.go bash)\n")
+	for _, t := range tools {
+		p := t.New()
+		p.Name = t.Name
+		script := flaggy.GenerateBashCompletion(p)
+		b.WriteString(script)
+		fn := "_" + strings.ReplaceAll(t.Name, "-", "_") + "_complete"
+		if t.Path != "" && t.Path != t.Name {
+			fmt.Fprintf(&b, "complete -F %s %s\n", fn, t.Path)
+			if !strings.HasPrefix(t.Path, "./") {
+				fmt.Fprintf(&b, "complete -F %s ./%s\n", fn, t.Path)
+			}
+		}
+	}
+	return b.String()
+}

internal/cli/cli_test.go

@@ -0,0 +1,77 @@
+package cli
+
+import (
+	"errors"
+	"strings"
+	"testing"
+
+	"github.com/integrii/flaggy"
+)
+
+func TestParseBoolAndIntAnyPosition(t *testing.T) {
+	p := New("t")
+	jsonOut := false
+	n := 20
+	q := ""
+	p.Bool(&jsonOut, "", "json", "JSON")
+	p.Int(&n, "n", "n", "limit")
+	p.AddPositionalValue(&q, "query", 1, false, "q")
+	if err := Parse(p, []string{"two", "words", "--json", "-n", "5"}); err != nil {
+		t.Fatal(err)
+	}
+	got := Query(q, p.TrailingArguments)
+	if got != "two words" || !jsonOut || n != 5 {
+		t.Fatalf("q=%q json=%v n=%d", got, jsonOut, n)
+	}
+}
+
+func TestParseUnknownFlagIsError(t *testing.T) {
+	p := New("t")
+	jsonOut := false
+	p.Bool(&jsonOut, "", "json", "JSON")
+	if err := Parse(p, []string{"--nope"}); err == nil {
+		t.Fatal("unknown flag accepted")
+	}
+}
+
+func TestParseHelpIsErrHelp(t *testing.T) {
+	p := New("t")
+	jsonOut := false
+	p.Bool(&jsonOut, "", "json", "JSON")
+	err := Parse(p, []string{"--help"})
+	if !errors.Is(err, ErrHelp) {
+		t.Fatalf("got %v", err)
+	}
+}
+
+func TestParseMissingFlagValueIsError(t *testing.T) {
+	p := New("t")
+	n := 0
+	p.Int(&n, "", "hop", "hop")
+	if err := Parse(p, []string{"--hop"}); err == nil {
+		t.Fatal("expected missing value error")
+	}
+}
+
+func TestBashScriptNamesShebangPath(t *testing.T) {
+	out := BashScript([]Tool{{
+		Path: "bin/brain/search.go",
+		Name: "brain-search",
+		New:  newSearchLike,
+	}})
+	if !strings.Contains(out, "--json") || !strings.Contains(out, "--hop") {
+		t.Fatalf("flags missing:\n%s", out)
+	}
+	if !strings.Contains(out, "complete -F") || !strings.Contains(out, "bin/brain/search.go") {
+		t.Fatalf("shebang complete missing:\n%s", out)
+	}
+}
+
+func newSearchLike() *flaggy.Parser {
+	p := New("brain-search")
+	jsonOut := false
+	hop := 0
+	p.Bool(&jsonOut, "", "json", "JSON")
+	p.Int(&hop, "", "hop", "graph hop")
+	return p
+}

internal/cli/qa.go

@@ -0,0 +1,24 @@
+package cli
+
+import "github.com/integrii/flaggy"
+
+type QAStats struct {
+	JSONL string
+}
+
+func QAParser() *flaggy.Parser {
+	c := QAStats{}
+	return BindQA(&c)
+}
+
+func BindQA(c *QAStats) *flaggy.Parser {
+	p := New("qa-stats")
+	p.Description = "DuckDB quantiles / JSONL count"
+	p.String(&c.JSONL, "", "jsonl", "JSONL file (else stdin JSON [float,…])")
+	return p
+}
+
+func ParseQAStats(args []string) (QAStats, error) {
+	var c QAStats
+	return c, Parse(BindQA(&c), args)
+}

internal/duckstats/duckstats.go

@@ -0,0 +1,47 @@
+// Package duckstats runs in-process DuckDB for columnar aggregates.
+// Graph facts stay in Ladybug. Web-search KV cache stays modernc sqlite.
+package duckstats
+
+import (
+	"database/sql"
+	"fmt"
+
+	_ "github.com/duckdb/duckdb-go/v2"
+)
+
+type Stats struct {
+	N   int     `json:"n"`
+	Min float64 `json:"min"`
+	P50 float64 `json:"p50"`
+	P95 float64 `json:"p95"`
+	Max float64 `json:"max"`
+	Avg float64 `json:"avg"`
+}
+
+func Quantiles(samples []float64) (Stats, error) {
+	if len(samples) == 0 {
+		return Stats{}, fmt.Errorf("duckstats: empty samples")
+	}
+	db, err := sql.Open("duckdb", "")
+	if err != nil {
+		return Stats{}, err
+	}
+	defer db.Close()
+	var s Stats
+	err = db.QueryRow(`
+SELECT count(v), min(v), quantile_cont(v, 0.5), quantile_cont(v, 0.95), max(v), avg(v)
+FROM (SELECT unnest(?) AS v)`, samples).Scan(
+		&s.N, &s.Min, &s.P50, &s.P95, &s.Max, &s.Avg)
+	return s, err
+}
+
+func CountJSONL(path string) (int64, error) {
+	db, err := sql.Open("duckdb", "")
+	if err != nil {
+		return 0, err
+	}
+	defer db.Close()
+	var n int64
+	err = db.QueryRow(`SELECT count(*) FROM read_json_auto(?)`, path).Scan(&n)
+	return n, err
+}

internal/duckstats/duckstats_test.go

@@ -0,0 +1,51 @@
+package duckstats
+
+import (
+	"os"
+	"testing"
+)
+
+func TestQuantilesEmpty(t *testing.T) {
+	_, err := Quantiles(nil)
+	if err == nil {
+		t.Fatal("empty slice must error")
+	}
+}
+
+func TestQuantilesOdd(t *testing.T) {
+	s, err := Quantiles([]float64{1, 2, 3, 4, 5})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if s.N != 5 {
+		t.Fatalf("n=%d", s.N)
+	}
+	if s.Min != 1 || s.Max != 5 {
+		t.Fatalf("min=%v max=%v", s.Min, s.Max)
+	}
+	if s.P50 != 3 {
+		t.Fatalf("p50=%v want 3", s.P50)
+	}
+	if s.Avg != 3 {
+		t.Fatalf("avg=%v want 3", s.Avg)
+	}
+	if s.P95 < 4.5 || s.P95 > 5 {
+		t.Fatalf("p95=%v want in [4.5,5]", s.P95)
+	}
+}
+
+func TestCountJSONL(t *testing.T) {
+	dir := t.TempDir()
+	p := dir + "/rows.jsonl"
+	body := "{\"ms\":1}\n{\"ms\":2}\n{\"ms\":3}\n"
+	if err := os.WriteFile(p, []byte(body), 0o600); err != nil {
+		t.Fatal(err)
+	}
+	n, err := CountJSONL(p)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if n != 3 {
+		t.Fatalf("count=%d want 3", n)
+	}
+}

internal/facts/contradict.go

@@ -0,0 +1,120 @@
+// Package facts is cgo-free evidence rules (D16 contradictions).
+package facts
+
+import "strconv"
+
+const (
+	ConfConfirmed  = "confirmed"
+	ConfHypothesis = "hypothesis"
+
+	RuleUnresolved        = "unresolved"
+	RuleTemporalFreshness = "temporal_freshness"
+	RuleAuthorityPairing  = "authority_pairing"
+	RuleTwoSource         = "two_source"
+	RuleSingleSource      = "single_source"
+
+	KindRuntime   = "runtime"
+	KindConfig    = "config"
+	KindNarrative = "narrative"
+)
+
+// Source is one independent pointer on a yes or no side.
+type Source struct {
+	ID    string `json:"id"`
+	Kind  string `json:"kind"`
+	When  string `json:"when,omitempty"`
+	Stale bool   `json:"stale,omitempty"`
+}
+
+// Claim is one assertion with yes/no evidence lists.
+type Claim struct {
+	Text string   `json:"text"`
+	Yes  []Source `json:"yes"`
+	No   []Source `json:"no"`
+}
+
+// Result is audit output. Confirmed=false means `(not confirmed)`.
+type Result struct {
+	Text       string `json:"text"`
+	Confidence string `json:"confidence"`
+	Confirmed  bool   `json:"confirmed"`
+	Rule       string `json:"rule"`
+	Winner     string `json:"winner,omitempty"`
+	YesN       int    `json:"yes"`
+	NoN        int    `json:"no"`
+}
+
+func independent(ss []Source) int {
+	seen := map[string]struct{}{}
+	for i, s := range ss {
+		id := s.ID
+		if id == "" {
+			id = s.Kind + "#" + strconv.Itoa(i)
+		}
+		seen[id] = struct{}{}
+	}
+	return len(seen)
+}
+
+func freshN(ss []Source) int {
+	n := 0
+	for _, s := range ss {
+		if !s.Stale {
+			n++
+		}
+	}
+	return n
+}
+
+func strongN(ss []Source) int {
+	n := 0
+	for _, s := range ss {
+		if s.Kind == KindRuntime || s.Kind == KindConfig {
+			n++
+		}
+	}
+	return n
+}
+
+func out(c Claim, conf, rule, winner string) Result {
+	return Result{
+		Text:       c.Text,
+		Confidence: conf,
+		Confirmed:  conf == ConfConfirmed,
+		Rule:       rule,
+		Winner:     winner,
+		YesN:       independent(c.Yes),
+		NoN:        independent(c.No),
+	}
+}
+
+// Adjudicate applies D16: ≥2 yes vs ≥2 no stays hypothesis until a rule fires.
+// Order: temporal_freshness, then authority_pairing (A/B beats narrative C).
+func Adjudicate(c Claim) Result {
+	yesN := independent(c.Yes)
+	noN := independent(c.No)
+	if yesN < 2 || noN < 2 {
+		if yesN >= 2 {
+			return out(c, ConfConfirmed, RuleTwoSource, "yes")
+		}
+		if noN >= 2 {
+			return out(c, ConfConfirmed, RuleTwoSource, "no")
+		}
+		return out(c, ConfHypothesis, RuleSingleSource, "")
+	}
+	yf, nf := freshN(c.Yes), freshN(c.No)
+	if yf >= 2 && nf < 2 {
+		return out(c, ConfConfirmed, RuleTemporalFreshness, "yes")
+	}
+	if nf >= 2 && yf < 2 {
+		return out(c, ConfConfirmed, RuleTemporalFreshness, "no")
+	}
+	ys, ns := strongN(c.Yes), strongN(c.No)
+	if ys >= 2 && ns < 2 {
+		return out(c, ConfConfirmed, RuleAuthorityPairing, "yes")
+	}
+	if ns >= 2 && ys < 2 {
+		return out(c, ConfConfirmed, RuleAuthorityPairing, "no")
+	}
+	return out(c, ConfHypothesis, RuleUnresolved, "")
+}

internal/facts/contradict_test.go

@@ -0,0 +1,86 @@
+package facts
+
+import "testing"
+
+func src(id, kind string, stale bool) Source {
+	return Source{ID: id, Kind: kind, Stale: stale}
+}
+
+func TestTwoVsTwoStaysHypothesis(t *testing.T) {
+	c := Claim{
+		Text: "svc listens on 443",
+		Yes: []Source{
+			src("docker-ps", KindRuntime, false),
+			src("compose", KindConfig, false),
+		},
+		No: []Source{
+			src("docker-ps-old", KindRuntime, false),
+			src("compose-old", KindConfig, false),
+		},
+	}
+	r := Adjudicate(c)
+	if r.Confirmed || r.Confidence != ConfHypothesis || r.Rule != RuleUnresolved {
+		t.Fatalf("2v2 must stay (not confirmed): %+v", r)
+	}
+	if r.Winner != "" {
+		t.Fatalf("unresolved must not name a winner: %+v", r)
+	}
+}
+
+func TestTemporalFreshnessResolvesStaleSide(t *testing.T) {
+	c := Claim{
+		Text: "svc listens on 443",
+		Yes: []Source{
+			src("docker-ps", KindRuntime, false),
+			src("compose", KindConfig, false),
+		},
+		No: []Source{
+			src("old-readme", KindNarrative, true),
+			src("old-wiki", KindNarrative, true),
+		},
+	}
+	r := Adjudicate(c)
+	if !r.Confirmed || r.Rule != RuleTemporalFreshness || r.Winner != "yes" {
+		t.Fatalf("fresh yes vs stale no: %+v", r)
+	}
+}
+
+func TestAuthorityPairingBeatsNarrative(t *testing.T) {
+	c := Claim{
+		Text: "svc listens on 443",
+		Yes: []Source{
+			src("docker-ps", KindRuntime, false),
+			src("compose", KindConfig, false),
+		},
+		No: []Source{
+			src("readme", KindNarrative, false),
+			src("wiki", KindNarrative, false),
+		},
+	}
+	r := Adjudicate(c)
+	if !r.Confirmed || r.Rule != RuleAuthorityPairing || r.Winner != "yes" {
+		t.Fatalf("A×B vs C×C: %+v", r)
+	}
+}
+
+func TestTwoSourceYesIsConfirmed(t *testing.T) {
+	c := Claim{
+		Text: "arc-1 runs Matrix",
+		Yes: []Source{
+			src("compose", KindConfig, false),
+			src("docker-ps", KindRuntime, false),
+		},
+	}
+	r := Adjudicate(c)
+	if !r.Confirmed || r.Rule != RuleTwoSource || r.Winner != "yes" {
+		t.Fatalf("%+v", r)
+	}
+}
+
+func TestSingleSourceIsHypothesis(t *testing.T) {
+	c := Claim{Text: "maybe", Yes: []Source{src("readme", KindNarrative, false)}}
+	r := Adjudicate(c)
+	if r.Confirmed || r.Rule != RuleSingleSource {
+		t.Fatalf("%+v", r)
+	}
+}

internal/facts/interval.go

@@ -0,0 +1,44 @@
+package facts
+
+// Interval of truth for a fact leaf (D24 / OQ5). Not D16 source staleness.
+//
+// Empty valid_from and valid_to means "always" (legacy leafs). Empty asOf
+// means "do not filter". Dates compare as YYYY-MM-DD (lexicographic).
+
+// NormalizeDay keeps the calendar day from ISO-8601 or bare dates.
+func NormalizeDay(s string) string {
+	s = trimSpace(s)
+	if len(s) >= 10 && s[4] == '-' && s[7] == '-' {
+		return s[:10]
+	}
+	return s
+}
+
+func trimSpace(s string) string {
+	i, j := 0, len(s)
+	for i < j && (s[i] == ' ' || s[i] == '\t' || s[i] == '\n' || s[i] == '\r') {
+		i++
+	}
+	for j > i && (s[j-1] == ' ' || s[j-1] == '\t' || s[j-1] == '\n' || s[j-1] == '\r') {
+		j--
+	}
+	return s[i:j]
+}
+
+// ActiveAt reports whether a fact with [validFrom, validTo] holds at asOf.
+// validTo empty = open-ended. Both ends inclusive.
+func ActiveAt(validFrom, validTo, asOf string) bool {
+	asOf = NormalizeDay(asOf)
+	if asOf == "" {
+		return true
+	}
+	from := NormalizeDay(validFrom)
+	to := NormalizeDay(validTo)
+	if from != "" && asOf < from {
+		return false
+	}
+	if to != "" && asOf > to {
+		return false
+	}
+	return true
+}

internal/facts/interval_test.go

@@ -0,0 +1,73 @@
+package facts
+
+import "testing"
+
+func TestActiveAtOpenEnded(t *testing.T) {
+	// works at Y from 2025-07-16, no end
+	if !ActiveAt("2025-07-16", "", "2025-07-16") {
+		t.Fatal("inclusive valid_from")
+	}
+	if !ActiveAt("2025-07-16", "", "2026-01-01") {
+		t.Fatal("open-ended valid_to")
+	}
+	if ActiveAt("2025-07-16", "", "2025-07-15") {
+		t.Fatal("before valid_from must be inactive")
+	}
+}
+
+func TestActiveAtClosedInterval(t *testing.T) {
+	// works at X 2024-03-01 .. 2025-07-15
+	if !ActiveAt("2024-03-01", "2025-07-15", "2025-01-01") {
+		t.Fatal("mid interval")
+	}
+	if !ActiveAt("2024-03-01", "2025-07-15", "2024-03-01") {
+		t.Fatal("inclusive start")
+	}
+	if !ActiveAt("2024-03-01", "2025-07-15", "2025-07-15") {
+		t.Fatal("inclusive end")
+	}
+	if ActiveAt("2024-03-01", "2025-07-15", "2025-07-16") {
+		t.Fatal("day after end")
+	}
+	if ActiveAt("2024-03-01", "2025-07-15", "2024-02-28") {
+		t.Fatal("day before start")
+	}
+}
+
+func TestActiveAtEmptyIntervalAlwaysTrue(t *testing.T) {
+	// legacy leafs without intervals stay visible for any as-of
+	if !ActiveAt("", "", "2025-01-01") {
+		t.Fatal("empty interval must remain active")
+	}
+	if !ActiveAt("", "", "") {
+		t.Fatal("no as-of means all active")
+	}
+}
+
+func TestActiveAtEmptyAsOfKeepsAll(t *testing.T) {
+	if !ActiveAt("2099-01-01", "2099-12-31", "") {
+		t.Fatal("empty as-of must not filter")
+	}
+}
+
+func TestAsOfPickXNotY(t *testing.T) {
+	// Acceptance from #36: as of 2025-01-01 → X, not Y
+	xFrom, xTo := "2024-03-01", "2025-07-15"
+	yFrom, yTo := "2025-07-16", ""
+	asOf := "2025-01-01"
+	if !ActiveAt(xFrom, xTo, asOf) {
+		t.Fatal("X must be active as of 2025-01-01")
+	}
+	if ActiveAt(yFrom, yTo, asOf) {
+		t.Fatal("Y must be inactive as of 2025-01-01")
+	}
+}
+
+func TestNormalizeDayTrimsTime(t *testing.T) {
+	if NormalizeDay("2025-01-01T12:00:00Z") != "2025-01-01" {
+		t.Fatalf("got %q", NormalizeDay("2025-01-01T12:00:00Z"))
+	}
+	if NormalizeDay("2025-01-01") != "2025-01-01" {
+		t.Fatalf("got %q", NormalizeDay("2025-01-01"))
+	}
+}

internal/gitlog/args.go

@@ -0,0 +1,51 @@
+package gitlog
+
+import (
+	"fmt"
+	"time"
+
+	"github.com/eSlider/2dph/internal/cli"
+	"github.com/integrii/flaggy"
+)
+
+type CLI struct {
+	Repo, Root, Since string
+	Limit             int
+	JSONOut           bool
+}
+
+func Parser() *flaggy.Parser {
+	c := CLI{}
+	return Bind(&c)
+}
+
+func Bind(c *CLI) *flaggy.Parser {
+	p := cli.New("git-import")
+	p.Description = "go-git history → commit leafs"
+	p.Bool(&c.JSONOut, "", "json", "JSON output")
+	p.Int(&c.Limit, "", "limit", "max commits (0 = all)")
+	p.String(&c.Since, "", "since", "RFC3339 or YYYY-MM-DD")
+	p.String(&c.Root, "", "root", "scan dir for git repos")
+	p.AddPositionalValue(&c.Repo, "repo", 1, false, "git repo path")
+	return p
+}
+
+func ParseArgs(args []string) (CLI, error) {
+	var c CLI
+	if err := cli.Parse(Bind(&c), args); err != nil {
+		return c, err
+	}
+	return c, nil
+}
+
+func ParseSince(s string) (time.Time, error) {
+	if s == "" {
+		return time.Time{}, nil
+	}
+	for _, layout := range []string{time.RFC3339, "2006-01-02"} {
+		if t, err := time.Parse(layout, s); err == nil {
+			return t, nil
+		}
+	}
+	return time.Time{}, fmt.Errorf("cannot parse --since %q", s)
+}

internal/httpapi/mcp.go

@@ -105,11 +105,18 @@ func (s *Server) mcpCall(r *http.Request, params json.RawMessage) (any, error) {
 		if limit < 1 || limit > 100 {
 			return mcpText(`{"error":"n must be int 1..100"}`, true), nil
 		}
+		asOf := ""
+		if raw, ok := p.Arguments["as_of"]; ok {
+			asOf = strings.TrimSpace(fmt.Sprint(raw))
+			if asOf == "<nil>" {
+				asOf = ""
+			}
+		}
 		if !s.tryAcquire(r) {
 			return nil, fmt.Errorf("cancelled")
 		}
 		defer s.release()
-		body, err = s.api.Search(r.Context(), q, limit)
+		body, err = s.api.Search(r.Context(), q, limit, asOf)
 	case "get":
 		id := strings.TrimSpace(fmt.Sprint(p.Arguments["id"]))
 		if id == "" || id == "<nil>" {
@@ -144,7 +151,15 @@ func (s *Server) mcpCall(r *http.Request, params json.RawMessage) (any, error) {
 			return nil, fmt.Errorf("cancelled")
 		}
 		defer s.release()
-		body, err = s.api.Ingest(r.Context())
+		var payload []byte
+		text := strings.TrimSpace(fmt.Sprint(p.Arguments["text"]))
+		if text != "" && text != "<nil>" {
+			payload, err = json.Marshal(p.Arguments)
+			if err != nil {
+				return nil, err
+			}
+		}
+		body, err = s.api.Ingest(r.Context(), payload)
 	default:
 		return nil, fmt.Errorf("unknown tool %s", p.Name)
 	}

internal/httpapi/server.go

@@ -11,6 +11,7 @@ import (
 	"context"
 	"encoding/json"
 	"errors"
+	"io"
 	"log"
 	"net/http"
 	"os"
@@ -23,11 +24,11 @@ import (
 
 // API is the in-process brain surface. Production serve.go wires internal/brain.
 type API interface {
-	Search(ctx context.Context, query string, limit int) ([]byte, error)
+	Search(ctx context.Context, query string, limit int, asOf string) ([]byte, error)
 	Get(ctx context.Context, id string, body bool) ([]byte, error)
 	Stats(ctx context.Context) ([]byte, error)
 	Audit(ctx context.Context) ([]byte, error)
-	Ingest(ctx context.Context) ([]byte, error)
+	Ingest(ctx context.Context, body []byte) ([]byte, error)
 }
 
 type Server struct {
@@ -59,7 +60,7 @@ func (s *Server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	case PathAudit:
 		s.handleJSON(w, r, s.api.Audit)
 	case PathIngest:
-		s.handleJSON(w, r, s.api.Ingest)
+		s.handleIngest(w, r)
 	case PathOpenAPI:
 		s.handleOpenAPI(w, r)
 	case PathMCP:
@@ -84,11 +85,12 @@ func (s *Server) handleSearch(w http.ResponseWriter, r *http.Request) {
 		}
 		limit = n
 	}
+	asOf := strings.TrimSpace(r.URL.Query().Get("as_of"))
 	if !s.acquire(w, r) {
 		return
 	}
 	defer s.release()
-	body, err := s.api.Search(r.Context(), q, limit)
+	body, err := s.api.Search(r.Context(), q, limit, asOf)
 	writeAPI(w, body, err)
 }
 
@@ -116,6 +118,24 @@ func (s *Server) handleJSON(w http.ResponseWriter, r *http.Request, fn func(cont
 	writeAPI(w, body, err)
 }
 
+func (s *Server) handleIngest(w http.ResponseWriter, r *http.Request) {
+	var raw []byte
+	if r.Method == http.MethodPost {
+		b, err := io.ReadAll(io.LimitReader(r.Body, 1<<20))
+		if err != nil {
+			writeJSON(w, http.StatusBadRequest, map[string]any{"error": "read body"})
+			return
+		}
+		raw = b
+	}
+	if !s.acquire(w, r) {
+		return
+	}
+	defer s.release()
+	body, err := s.api.Ingest(r.Context(), raw)
+	writeAPI(w, body, err)
+}
+
 func (s *Server) tryAcquire(r *http.Request) bool {
 	return s.acquire(nopWriter{}, r)
 }
@@ -168,13 +188,18 @@ type ExecSearcher struct {
 	Timeout time.Duration
 }
 
-func (b ExecSearcher) Search(ctx context.Context, query string, limit int) ([]byte, error) {
+func (b ExecSearcher) Search(ctx context.Context, query string, limit int, asOf string) ([]byte, error) {
 	if b.Timeout == 0 {
 		b.Timeout = 60 * time.Second
 	}
 	ctx, cancel := context.WithTimeout(ctx, b.Timeout)
 	defer cancel()
-	cmd := exec.CommandContext(ctx, b.CmdPath, "--json", "-n", strconv.Itoa(limit), query)
+	args := []string{"--json", "-n", strconv.Itoa(limit)}
+	if asOf != "" {
+		args = append(args, "--as-of", asOf)
+	}
+	args = append(args, query)
+	cmd := exec.CommandContext(ctx, b.CmdPath, args...)
 	out, err := cmd.Output()
 	if err != nil {
 		var exitErr *exec.ExitError
@@ -191,11 +216,30 @@ func (ExecSearcher) Get(context.Context, string, bool) ([]byte, error) {
 }
 func (ExecSearcher) Stats(context.Context) ([]byte, error) { return nil, errUnimplemented }
 func (ExecSearcher) Audit(context.Context) ([]byte, error) { return nil, errUnimplemented }
-func (ExecSearcher) Ingest(context.Context) ([]byte, error) {
+func (b ExecSearcher) Ingest(ctx context.Context, body []byte) ([]byte, error) {
+	if len(strings.TrimSpace(string(body))) == 0 {
 		return json.Marshal(map[string]any{
-		"mode":    "rebuild",
+			"mode":    "add",
-		"command": "bin/brain/index.go --rebuild",
+			"command": "bin/brain/add.go",
+			"rebuild": "bin/brain/index.go --rebuild",
 		})
+	}
+	root := os.Getenv("KB_ROOT")
+	if root == "" {
+		root = "."
+	}
+	cmd := exec.CommandContext(ctx, filepath.Join(root, "bin/kb/add"), "--json")
+	cmd.Stdin = strings.NewReader(string(body))
+	cmd.Dir = root
+	out, err := cmd.Output()
+	if err != nil {
+		var exitErr *exec.ExitError
+		if errors.As(err, &exitErr) {
+			return nil, errors.New("add failed: " + strings.TrimSpace(string(exitErr.Stderr)))
+		}
+		return nil, err
+	}
+	return out, nil
 }
 
 func defaultSearchCmd(root string) string {

internal/httpapi/server_test.go

@@ -1,6 +1,7 @@
 package httpapi
 
 import (
+	"bytes"
 	"context"
 	"encoding/json"
 	"net/http"
@@ -20,10 +21,10 @@ type fakeSearcher struct {
 	calls    int
 	active   atomic.Int32
 	maxSeen  atomic.Int32
-	callback func(q string, limit int) ([]byte, error)
+	callback func(q string, limit int, asOf string) ([]byte, error)
 }
 
-func (f *fakeSearcher) Search(ctx context.Context, query string, limit int) ([]byte, error) {
+func (f *fakeSearcher) Search(ctx context.Context, query string, limit int, asOf string) ([]byte, error) {
 	f.mu.Lock()
 	f.calls++
 	f.mu.Unlock()
@@ -43,7 +44,7 @@ func (f *fakeSearcher) Search(ctx context.Context, query string, limit int) ([]b
 		}
 	}
 	if f.callback != nil {
-		return f.callback(query, limit)
+		return f.callback(query, limit, asOf)
 	}
 	return []byte(`{"query":"` + query + `","count":0,"results":[]}`), nil
 }
@@ -64,8 +65,11 @@ func (f *fakeSearcher) Audit(context.Context) ([]byte, error) {
 	return []byte(`{"status":"ok"}`), nil
 }
 
-func (f *fakeSearcher) Ingest(context.Context) ([]byte, error) {
+func (f *fakeSearcher) Ingest(_ context.Context, body []byte) ([]byte, error) {
-	return []byte(`{"mode":"rebuild","command":"bin/brain/index.go --rebuild"}`), nil
+	if len(bytes.TrimSpace(body)) == 0 {
+		return []byte(`{"mode":"add","command":"bin/brain/add.go"}`), nil
+	}
+	return []byte(`{"mode":"add","ids":["fake-leaf"]}`), nil
 }
 
 func (f *fakeSearcher) count() int {
@@ -105,7 +109,7 @@ func TestSearchMissingQuery(t *testing.T) {
 }
 
 func TestSearchReturnsSearcherResult(t *testing.T) {
-	fs := &fakeSearcher{callback: func(q string, limit int) ([]byte, error) {
+	fs := &fakeSearcher{callback: func(q string, limit int, asOf string) ([]byte, error) {
 		return []byte(`{"query":"` + q + `","count":1,"results":[{"id":"x"}]}`), nil
 	}}
 	h := NewServer(fs, 1)
@@ -164,7 +168,7 @@ func TestSearchRejectsBadLimit(t *testing.T) {
 }
 
 func TestGetLeaf(t *testing.T) {
-	fs := &fakeSearcher{callback: func(q string, limit int) ([]byte, error) {
+	fs := &fakeSearcher{callback: func(q string, limit int, asOf string) ([]byte, error) {
 		return []byte(`{}`), nil
 	}}
 	h := NewServer(fs, 1)
@@ -193,6 +197,27 @@ func TestStatsAuditIngest(t *testing.T) {
 	}
 }
 
+func TestIngestIsAddNotRebuildHint(t *testing.T) {
+	h := NewServer(&fakeSearcher{}, 1)
+	code, body := get(t, h, "/ingest")
+	if code != http.StatusOK {
+		t.Fatalf("GET /ingest code = %d body=%s", code, body)
+	}
+	if strings.Contains(string(body), `"add":"v2"`) || strings.Contains(string(body), "write is v2") {
+		t.Fatalf("GET /ingest still a v2 hint: %s", body)
+	}
+	if !strings.Contains(string(body), "bin/brain/add.go") {
+		t.Fatalf("GET /ingest should name add.go: %s", body)
+	}
+	code, body = postJSON(t, h, "/ingest", `{"text":"hello","root":"info","source":"t"}`)
+	if code != http.StatusOK {
+		t.Fatalf("POST /ingest code = %d body=%s", code, body)
+	}
+	if !strings.Contains(string(body), "fake-leaf") {
+		t.Fatalf("POST /ingest should add: %s", body)
+	}
+}
+
 func TestHTTPPackageDoesNotExecPython(t *testing.T) {
 	raw, err := os.ReadFile("server.go")
 	if err != nil {

internal/httpapi/spec.go

@@ -35,6 +35,7 @@ var Ops = []Op{
 		Params: []Param{
 			{Name: "q", In: "query", Type: "string", Description: "search query", Required: true},
 			{Name: "n", In: "query", Type: "integer", Description: "hit limit 1..100 (default 10)"},
+			{Name: "as_of", In: "query", Type: "string", Description: "YYYY-MM-DD; keep facts active on that day (D24)"},
 		},
 	},
 	{
@@ -47,7 +48,17 @@ var Ops = []Op{
 	},
 	{Path: PathStats, Method: "get", ID: "stats", Summary: "index health", MCP: true},
 	{Path: PathAudit, Method: "get", ID: "audit", Summary: "facts confidence histogram", MCP: true},
-	{Path: PathIngest, Method: "get", ID: "ingest", Summary: "rebuild hint (write is v2)", MCP: true},
+	{
+		Path: PathIngest, Method: "post", ID: "ingest", Summary: "add a leaf without rebuild",
+		MCP: true,
+		Params: []Param{
+			{Name: "text", In: "query", Type: "string", Description: "leaf text (omit for CLI hint)"},
+			{Name: "root", In: "query", Type: "string", Description: "facts or info (default info)"},
+			{Name: "source", In: "query", Type: "string", Description: "evidence pointer; facts need two sources"},
+			{Name: "valid_from", In: "query", Type: "string", Description: "fact interval start YYYY-MM-DD (D24)"},
+			{Name: "valid_to", In: "query", Type: "string", Description: "fact interval end YYYY-MM-DD inclusive (D24)"},
+		},
+	},
 	{Path: PathOpenAPI, Method: "get", ID: "openapi", Summary: "OpenAPI 3 document for this server"},
 }
 

internal/httpapi/spec_test.go

@@ -38,11 +38,24 @@ func TestMCPToolsMatchOpenAPIPaths(t *testing.T) {
 			t.Fatalf("MCP tool %s has no OpenAPI path %s", tool.Name, path)
 		}
 	}
-	for _, need := range []string{"search", "get", "stats", "audit"} {
+	for _, need := range []string{"search", "get", "stats", "audit", "ingest"} {
 		if !names[need] {
 			t.Fatalf("MCP tools missing %s: %v", need, names)
 		}
 	}
+	var ingest MCPTool
+	for _, tool := range tools {
+		if tool.Name == "ingest" {
+			ingest = tool
+			break
+		}
+	}
+	if strings.Contains(ingest.Description, "v2") {
+		t.Fatalf("ingest still a v2 hint: %s", ingest.Description)
+	}
+	if !strings.Contains(ingest.Description, "add") {
+		t.Fatalf("ingest should describe add: %s", ingest.Description)
+	}
 }
 
 func TestOpenAPIHTTP(t *testing.T) {

internal/mdleaves/args.go

@@ -0,0 +1,41 @@
+package mdleaves
+
+import (
+	"github.com/eSlider/2dph/internal/cli"
+	"github.com/integrii/flaggy"
+)
+
+type CLI struct {
+	Root    string
+	Files   string
+	JSONOut bool
+}
+
+func Parser() *flaggy.Parser {
+	c := CLI{Root: "."}
+	return Bind(&c)
+}
+
+func Bind(c *CLI) *flaggy.Parser {
+	if c.Root == "" {
+		c.Root = "."
+	}
+	p := cli.New("markdown-import")
+	p.Description = "split markdown H2 leafs"
+	p.Bool(&c.JSONOut, "", "json", "JSON output")
+	p.String(&c.Files, "", "files", "comma-separated paths")
+	p.AddPositionalValue(&c.Root, "dir", 1, false, "markdown root")
+	return p
+}
+
+func ParseArgs(args []string) (CLI, error) {
+	c := CLI{Root: "."}
+	p := Bind(&c)
+	if err := cli.Parse(p, args); err != nil {
+		return c, err
+	}
+	if extra := cli.Query("", p.TrailingArguments); extra != "" && c.Root == "." {
+		c.Root = extra
+	}
+	return c, nil
+}

internal/mdleaves/leaf.go

@@ -0,0 +1,146 @@
+package mdleaves
+
+import (
+	"encoding/json"
+	"os"
+	"path/filepath"
+	"regexp"
+	"strings"
+)
+
+type Leaf struct {
+	Source  string `json:"source"`
+	Repo    string `json:"repo"`
+	Heading string `json:"heading"`
+	Text    string `json:"text"`
+	Type    string `json:"type"`
+	Status  string `json:"status"`
+	Related string `json:"related"`
+}
+
+type chunk struct {
+	Heading string
+	Text    string
+}
+
+var (
+	h1 = regexp.MustCompile(`^# \S`)
+	h2 = regexp.MustCompile(`^## \S`)
+)
+
+func ExtractFrontmatter(text string) (map[string]string, string) {
+	if !strings.HasPrefix(text, "---") {
+		return map[string]string{}, text
+	}
+	end := strings.Index(text[3:], "\n---")
+	if end == -1 {
+		return map[string]string{}, text
+	}
+	fm := strings.TrimSpace(text[3 : 3+end])
+	body := text[3+end+4:]
+	meta := map[string]string{}
+	for _, line := range strings.Split(fm, "\n") {
+		key, value, ok := strings.Cut(line, ":")
+		if !ok {
+			continue
+		}
+		meta[strings.TrimSpace(key)] = strings.Trim(strings.TrimSpace(value), `"'`)
+	}
+	return meta, body
+}
+
+func SplitLeafs(meta map[string]string, body string) []chunk {
+	lines := strings.Split(body, "\n")
+	title := ""
+	type hdr struct {
+		heading string
+		start   int
+	}
+	var headers []hdr
+	for i, line := range lines {
+		switch {
+		case h1.MatchString(line):
+			title = strings.TrimSpace(strings.TrimLeft(line, "#"))
+		case h2.MatchString(line):
+			headers = append(headers, hdr{strings.TrimSpace(strings.TrimLeft(line, "#")), i})
+		}
+	}
+	if len(headers) == 0 {
+		var kept []string
+		for _, l := range lines {
+			if strings.TrimSpace(l) != "" {
+				kept = append(kept, l)
+			}
+		}
+		return []chunk{{Heading: title, Text: strings.TrimSpace(strings.Join(kept, "\n"))}}
+	}
+	out := make([]chunk, 0, len(headers))
+	for idx, h := range headers {
+		end := len(lines)
+		if idx+1 < len(headers) {
+			end = headers[idx+1].start
+		}
+		var kept []string
+		for _, l := range lines[h.start:end] {
+			if strings.TrimSpace(l) != "" {
+				kept = append(kept, l)
+			}
+		}
+		text := strings.Join(kept, "\n")
+		if idx == 0 && title != "" {
+			text = title + "\n\n" + text
+		}
+		out = append(out, chunk{Heading: h.heading, Text: strings.TrimSpace(text)})
+	}
+	return out
+}
+
+func ToAll(text, path, repo string) []Leaf {
+	meta, body := ExtractFrontmatter(text)
+	if meta["type"] == "" {
+		meta["type"] = "reference"
+	}
+	if meta["status"] == "" {
+		meta["status"] = "current"
+	}
+	chunks := SplitLeafs(meta, body)
+	out := make([]Leaf, 0, len(chunks))
+	for _, c := range chunks {
+		out = append(out, Leaf{
+			Source:  path,
+			Repo:    repo,
+			Heading: c.Heading,
+			Text:    c.Text,
+			Type:    meta["type"],
+			Status:  meta["status"],
+			Related: meta["related"],
+		})
+	}
+	return out
+}
+
+func WalkMarkdown(root string) ([]string, error) {
+	var out []string
+	err := filepath.Walk(root, func(p string, info os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+		if info.IsDir() {
+			return nil
+		}
+		ext := strings.ToLower(filepath.Ext(p))
+		if ext == ".md" || ext == ".markdown" {
+			out = append(out, p)
+		}
+		return nil
+	})
+	return out, err
+}
+
+func EncodeJSON(leafs []Leaf) (string, error) {
+	raw, err := json.MarshalIndent(leafs, "", "  ")
+	if err != nil {
+		return "", err
+	}
+	return string(raw) + "\n", nil
+}

internal/mdleaves/leaf_test.go

@@ -0,0 +1,73 @@
+package mdleaves
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestSplitLeafsOnH2(t *testing.T) {
+	body := "# Title\n\n## One\n\nalpha\n\n## Two\n\nbeta\n"
+	leafs := SplitLeafs(map[string]string{}, body)
+	if len(leafs) != 2 {
+		t.Fatalf("n=%d", len(leafs))
+	}
+	if leafs[0].Heading != "One" || !strings.Contains(leafs[0].Text, "Title") {
+		t.Fatalf("first=%+v", leafs[0])
+	}
+	if leafs[1].Heading != "Two" || strings.Contains(leafs[1].Text, "Title") {
+		t.Fatalf("second=%+v", leafs[1])
+	}
+}
+
+func TestSplitLeafsNoH2IsWholeDoc(t *testing.T) {
+	body := "# Title\n\njust a paragraph\n"
+	leafs := SplitLeafs(nil, body)
+	if len(leafs) != 1 {
+		t.Fatalf("n=%d", len(leafs))
+	}
+	if leafs[0].Heading != "Title" {
+		t.Fatalf("heading=%q", leafs[0].Heading)
+	}
+	if !strings.Contains(leafs[0].Text, "just a paragraph") {
+		t.Fatalf("text=%q", leafs[0].Text)
+	}
+}
+
+func TestFrontmatterAndToAll(t *testing.T) {
+	raw := "---\ntype: howto\nstatus: current\nrelated: docs/design.md\n---\n# Doc\n\n## Step\n\ndo it\n"
+	got := ToAll(raw, "docs/x.md", "eSlider/2dph")
+	if len(got) != 1 {
+		t.Fatalf("n=%d", len(got))
+	}
+	if got[0].Type != "howto" || got[0].Status != "current" {
+		t.Fatalf("%+v", got[0])
+	}
+	if got[0].Source != "docs/x.md" || got[0].Repo != "eSlider/2dph" {
+		t.Fatalf("%+v", got[0])
+	}
+	if got[0].Related != "docs/design.md" {
+		t.Fatalf("related=%q", got[0].Related)
+	}
+}
+
+func TestEncodeJSONAndYAML(t *testing.T) {
+	leafs := ToAll("# Hi\n\nbody\n", "a.md", "")
+	js, err := EncodeJSON(leafs)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !strings.Contains(js, `"heading": "Hi"`) {
+		t.Fatalf("json=%s", js)
+	}
+	y := EncodeYAML(leafs)
+	if !strings.Contains(y, "heading: Hi") {
+		t.Fatalf("yaml=%s", y)
+	}
+}
+
+func TestDefaultsTypeAndStatus(t *testing.T) {
+	got := ToAll("# Hi\n\nbody\n", "a.md", "")
+	if got[0].Type != "reference" || got[0].Status != "current" {
+		t.Fatalf("%+v", got[0])
+	}
+}

internal/mdleaves/yaml.go

@@ -0,0 +1,36 @@
+package mdleaves
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+func EncodeYAML(leafs []Leaf) string {
+	if len(leafs) == 0 {
+		return "[]\n"
+	}
+	var b strings.Builder
+	for _, lf := range leafs {
+		b.WriteString("-\n")
+		writeKV(&b, "source", lf.Source)
+		writeKV(&b, "repo", lf.Repo)
+		writeKV(&b, "heading", lf.Heading)
+		writeKV(&b, "text", lf.Text)
+		writeKV(&b, "type", lf.Type)
+		writeKV(&b, "status", lf.Status)
+		writeKV(&b, "related", lf.Related)
+	}
+	return b.String()
+}
+
+func writeKV(b *strings.Builder, k, v string) {
+	fmt.Fprintf(b, "  %s: %s\n", k, yamlScalar(v))
+}
+
+func yamlScalar(s string) string {
+	if strings.Contains(s, "\n") || s == "" || strings.ContainsAny(s, ":#'\"[]{}&*!|>%@`") || s != strings.TrimSpace(s) {
+		return strconv.Quote(s)
+	}
+	return s
+}

internal/ocr/args.go

@@ -0,0 +1,35 @@
+package ocr
+
+import (
+	"fmt"
+
+	"github.com/eSlider/2dph/internal/cli"
+	"github.com/integrii/flaggy"
+)
+
+type CLI struct {
+	Path string
+}
+
+func Parser() *flaggy.Parser {
+	c := CLI{}
+	return Bind(&c)
+}
+
+func Bind(c *CLI) *flaggy.Parser {
+	p := cli.New("mail-ocr")
+	p.Description = "tesseract eng+deu on image or scanned PDF"
+	p.AddPositionalValue(&c.Path, "file", 1, false, "image or pdf")
+	return p
+}
+
+func ParseArgs(args []string) (CLI, error) {
+	var c CLI
+	if err := cli.Parse(Bind(&c), args); err != nil {
+		return c, err
+	}
+	if c.Path == "" {
+		return c, fmt.Errorf("usage: bin/mail/ocr.go <image|pdf>")
+	}
+	return c, nil
+}

internal/ocr/ocr.go

@@ -0,0 +1,162 @@
+// Package ocr runs Tesseract (eng+deu) on images and scanned PDFs.
+//
+// Default engine is the tesseract CLI, not gosseract CGO: Ladybug CGO stays
+// Zig-only (D21). Same engine, no gocv. OCR_ENGINE=paddle selects paddleocr
+// when that binary is on PATH (compose profile ocr-paddle).
+package ocr
+
+import (
+	"fmt"
+	"image"
+	"image/color"
+	"image/png"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+)
+
+const TessLang = "eng+deu"
+
+func ImageFile(path string) (string, error) {
+	engine := os.Getenv("OCR_ENGINE")
+	if engine == "paddle" {
+		return runPaddle(path)
+	}
+	return runTesseract(path)
+}
+
+func PDFFile(path string) (string, error) {
+	text, err := pdfToText(path)
+	if err == nil && strings.TrimSpace(text) != "" {
+		return strings.TrimSpace(text), nil
+	}
+	ocr, oerr := pdfPages(path)
+	if oerr != nil {
+		if err != nil {
+			return "", err
+		}
+		return "", oerr
+	}
+	if strings.TrimSpace(ocr) != "" {
+		return strings.TrimSpace(ocr), nil
+	}
+	if text != "" {
+		return strings.TrimSpace(text), nil
+	}
+	return "", fmt.Errorf("pdf has no text layer (ocr unavailable)")
+}
+
+func pdfToText(path string) (string, error) {
+	cmd := exec.Command("pdftotext", "-layout", path, "-")
+	out, err := cmd.Output()
+	if err != nil {
+		return "", err
+	}
+	return string(out), nil
+}
+
+func pdfPages(path string) (string, error) {
+	dir, err := os.MkdirTemp("", "2dph-ocr-")
+	if err != nil {
+		return "", err
+	}
+	defer os.RemoveAll(dir)
+	prefix := filepath.Join(dir, "page")
+	cmd := exec.Command("pdftoppm", "-png", "-r", "200", path, prefix)
+	if err := cmd.Run(); err != nil {
+		return "", err
+	}
+	matches, err := filepath.Glob(prefix + "*.png")
+	if err != nil {
+		return "", err
+	}
+	var parts []string
+	for _, img := range matches {
+		t, err := ImageFile(img)
+		if err != nil {
+			continue
+		}
+		if s := strings.TrimSpace(t); s != "" {
+			parts = append(parts, s)
+		}
+	}
+	return strings.Join(parts, "\n\n"), nil
+}
+
+func runTesseract(path string) (string, error) {
+	pre, err := preprocessFile(path)
+	if err != nil {
+		pre = path
+	} else {
+		defer os.Remove(pre)
+	}
+	cmd := exec.Command("tesseract", pre, "stdout", "-l", TessLang, "--psm", "6")
+	out, err := cmd.Output()
+	if err != nil {
+		return "", err
+	}
+	return strings.TrimSpace(string(out)), nil
+}
+
+func runPaddle(path string) (string, error) {
+	cmd := exec.Command("paddleocr", "ocr", "-i", path)
+	out, err := cmd.Output()
+	if err != nil {
+		return "", err
+	}
+	return strings.TrimSpace(string(out)), nil
+}
+
+func preprocessFile(path string) (string, error) {
+	f, err := os.Open(path)
+	if err != nil {
+		return "", err
+	}
+	defer f.Close()
+	img, err := png.Decode(f)
+	if err != nil {
+		return "", err
+	}
+	out := filepath.Join(os.TempDir(), filepath.Base(path)+".gray.png")
+	w, err := os.Create(out)
+	if err != nil {
+		return "", err
+	}
+	defer w.Close()
+	if err := png.Encode(w, GrayContrast(img)); err != nil {
+		os.Remove(out)
+		return "", err
+	}
+	return out, nil
+}
+
+// GrayContrast is a stdlib preprocess (no gocv): grayscale + stretch.
+func GrayContrast(src image.Image) image.Image {
+	b := src.Bounds()
+	dst := image.NewGray(b)
+	var minL, maxL uint8 = 255, 0
+	for y := b.Min.Y; y < b.Max.Y; y++ {
+		for x := b.Min.X; x < b.Max.X; x++ {
+			g := color.GrayModel.Convert(src.At(x, y)).(color.Gray)
+			if g.Y < minL {
+				minL = g.Y
+			}
+			if g.Y > maxL {
+				maxL = g.Y
+			}
+		}
+	}
+	span := int(maxL) - int(minL)
+	if span < 1 {
+		span = 1
+	}
+	for y := b.Min.Y; y < b.Max.Y; y++ {
+		for x := b.Min.X; x < b.Max.X; x++ {
+			g := color.GrayModel.Convert(src.At(x, y)).(color.Gray)
+			v := uint8((int(g.Y) - int(minL)) * 255 / span)
+			dst.SetGray(x, y, color.Gray{Y: v})
+		}
+	}
+	return dst
+}

internal/ocr/ocr_test.go

@@ -0,0 +1,54 @@
+package ocr
+
+import (
+	"image"
+	"image/color"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func TestGrayContrastStretches(t *testing.T) {
+	img := image.NewGray(image.Rect(0, 0, 2, 2))
+	img.SetGray(0, 0, color.Gray{Y: 64})
+	img.SetGray(0, 1, color.Gray{Y: 64})
+	img.SetGray(1, 0, color.Gray{Y: 64})
+	img.SetGray(1, 1, color.Gray{Y: 192})
+	out := GrayContrast(img).(*image.Gray)
+	if out.GrayAt(0, 0).Y != 0 {
+		t.Fatalf("min should map to 0, got %d", out.GrayAt(0, 0).Y)
+	}
+	if out.GrayAt(1, 1).Y != 255 {
+		t.Fatalf("max should map to 255, got %d", out.GrayAt(1, 1).Y)
+	}
+}
+
+func TestHelloPNGFixtureOCR(t *testing.T) {
+	if _, err := exec.LookPath("tesseract"); err != nil {
+		t.Skip("tesseract not installed")
+	}
+	path := filepath.Join("testdata", "hello.png")
+	got, err := ImageFile(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	up := strings.ToUpper(got)
+	if !strings.Contains(up, "HELLO") {
+		t.Fatalf("ocr %q missing HELLO", got)
+	}
+}
+
+func TestPaddleEngineUsesPaddleocrBinary(t *testing.T) {
+	t.Setenv("OCR_ENGINE", "paddle")
+	_, err := ImageFile(filepath.Join("testdata", "hello.png"))
+	if _, look := exec.LookPath("paddleocr"); look != nil {
+		if err == nil {
+			t.Fatal("expected error when paddleocr is missing")
+		}
+		return
+	}
+	if err != nil {
+		t.Fatal(err)
+	}
+}