feat: index facts extract and chats markdown on rebuild.

--with-facts / --facts-json write root=facts leafs; --with-chats picks up var/chats/md as info. WhatsApp sync stays out of v1 (Gitea #18).
feat: search --hop walks FROM_FILE to Person. (#30 )
2026-08-14 10:54:46 +01:00 · 2026-08-14 10:51:35 +01:00 · 2026-08-14 10:46:59 +01:00 · 2026-08-14 10:32:19 +01:00
33 changed files with 904 additions and 132 deletions
@@ -40,7 +40,7 @@ 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/markdown/ import.go (H2 leaf split; Python bin/md/import fallback)
@@ -65,7 +65,7 @@ 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 +
@@ -74,9 +74,9 @@ bin/brain/index.go --rebuild                                            # rebuil
  `pdftotext -layout` fast path (~15ms); textless/scanned PDFs fall back to
  docling (isolated subprocess — its native onnx can segfault the parent).
  Conversion never touches the brain DB (crash safety).
- `index_mail` is a deprecation shim for `bin/brain/index.go --rebuild`. Ladybug
-  corrupts its WAL when brand-new leafs are bulk-inserted while FTS/vector
-  indexes exist; a fresh DB with indexes created last is the only safe path.
+- `index_mail` is a deprecation shim for `bin/brain/index.go --rebuild`. Bulk
+  rebuild still deletes `var/kb.lbug` and creates FTS/HNSW last. Single-leaf
+  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.

@@ -89,6 +89,9 @@ bin/kb/search "query" [--repo X]                  # deprecated wrapper → bin/b
 bin/brain/search.go "query" [--root facts|info]   # deduction search → YAML
 bin/brain/search.go "query" --no-web              # local graph only
 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
@@ -31,9 +31,9 @@ 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 is Go + Zig CGO (D21). Python `bin/kb/{get,stats,eval}` is the CI fallback when Zig/libs are not fetched. Index/write stays Python (`compose --profile index`) 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. |
@@ -45,7 +45,7 @@ detective method: **a fact needs ≥2 independent sources or it is
 | 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 (`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`. |

 ## Architecture
@@ -57,8 +57,10 @@ 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
@@ -86,7 +88,9 @@ 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 / FROM_FILE / HAS_VERSION / AUTHORED / ABOUT / ASSOCIATED / SIMILAR_0.85`.
-`FROM_FILE` / `HAS_VERSION` exist in schema; search `--hop` does not walk them yet ([#17](https://git.produktor.io/eSlider/2dph/issues/17)).
+`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`.
@@ -155,23 +159,22 @@ 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) — **open**: [#18](https://git.produktor.io/eSlider/2dph/issues/18)
+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)

-Read path + MCP are in. The detective brain is not closed until the graph is
-**writable incrementally** and search can **walk** it. Board:
+Remaining: CI eval SoT. 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) | Write stays Python rebuild; `brain/add` / `POST /ingest` are hints. Ladybug 0.19 WAL corrupts if new leafs land while FTS/HNSW exist. |
-| 2 | [#17](https://git.produktor.io/eSlider/2dph/issues/17) | `--hop` errors. `FROM_FILE` / `HAS_VERSION` are in schema; search does not walk them. |
-| 3 | [#18](https://git.produktor.io/eSlider/2dph/issues/18) | Rebuild is mostly `info` (repo md + mail). `facts/extract` and chats are not a first-class index input. WhatsApp sync is a stub. |
-| 4 | [#15](https://git.produktor.io/eSlider/2dph/issues/15) | Lever = 2dph fact-check. Loop = PicoClaw/MCP `search` → `get` → `audit`. Specify in-repo, not only live config. |
+| 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) | GitHub CI recall still runs Python `bin/kb/eval`. |

 Does **not** block epic close: [#6](https://git.produktor.io/eSlider/2dph/issues/6) OCR, OQ1, OQ3, OQ4.
@@ -96,7 +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):

@@ -120,6 +120,8 @@ 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
 ```
@@ -128,8 +130,9 @@ bin/brain/search.go "invoice from last week"                            # same s

 - **LadybugDB** — single `var/kb.lbug`, Cypher + HNSW + BM25, embedded.
  Read tools (`get` / `stats` / `eval`) are Go + Zig CGO (`bin/cgo/zcc`).
-  Python fallbacks stay for CI until the runner fetches Zig. Write is
-  Compose profile `index` (`bin/brain/index.go`).
+  Python fallbacks stay for CI until the runner fetches Zig. Incremental
+  write is `bin/brain/add.go` (Python `kblib.add_leafs`). Bulk rebuild is
+  Compose profile `index` (`bin/brain/index.go --rebuild`).
 - **model2vec** — `potion-multilingual-128M` (256-dim), CPU, no Ollama
  runtime dependency.
 - facts and info split by `root` but written in the same transaction.
@@ -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:]))
+}
@@ -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
-// insert corrupts Ladybug 0.19 WAL). `add` is v2.
+// v1 write: bin/brain/add.go for one/few leafs (indexes may already exist).
+// Bulk mail/corpus still --rebuild (fresh file, indexes last).
 // NOTE: never run `gofmt -w` on this file — it breaks the shebang.
 package main

@@ -3,7 +3,7 @@
 //
 // 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
 //
@@ -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)
@@ -0,0 +1,114 @@
+#!/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_")
+    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_,
+        }]
+
+    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:]))
@@ -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():
-        DB_PATH.unlink()
+    dbpath.parent.mkdir(parents=True, exist_ok=True)
+    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


@@ -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

@@ -118,6 +118,97 @@ def upsert_leaf(conn: ladybug.Connection, *, text: str, root: str, confidence: s
    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.
+    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"),
+                )
+            )
+        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()
@@ -75,9 +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()
@@ -39,3 +39,59 @@ class IndexAdapterTest(unittest.TestCase):
        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()
@@ -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()
@@ -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 +161,39 @@ 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)
+

 if __name__ == "__main__":
    unittest.main()
@@ -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

@@ -139,24 +138,21 @@ 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",
-            ROOT / "docs" / "roadmap.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(
-                lie.search(text),
-                f"{path.relative_to(ROOT)} still claims --hop walks the graph",
+            self.assertIn("--hop", text, f"{path.relative_to(ROOT)} must document --hop")
+            self.assertNotIn(
+                "not implemented",
+                text.lower(),
+                f"{path.relative_to(ROOT)} still says hop is not implemented",
            )

    def test_docs_are_portable_diataxis(self) -> None:
@@ -27,9 +27,9 @@ 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
-not a walk; the flag errors. Schema has `FROM_FILE`; search does not
-use it ([#17](https://git.produktor.io/eSlider/2dph/issues/17)).
+`/health` `/search` `/get` `/stats` `/audit` `/ingest`). `--hop N` walks
+`FROM_FILE` → Commit → Person from each hit (max 3). Rebuild writes
+File edges ([#17](https://git.produktor.io/eSlider/2dph/issues/17)).

 Work board: [Gitea issues](https://git.produktor.io/eSlider/2dph/issues)
 ([epic #16](https://git.produktor.io/eSlider/2dph/issues/16)).
@@ -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.
@@ -34,9 +34,9 @@ bin/brain/search.go "question"
     is not evidence of absence; `--no-web` / `--root` skip it)
 ```

-`--hop` is not implemented. `FROM_FILE` / `HAS_VERSION` exist in schema;
-search does not walk them ([#17](https://git.produktor.io/eSlider/2dph/issues/17)).
-The flag is an error; it is not a graph walk.
+`--hop N` walks `Leaf-[:FROM_FILE]->File-[:HAS_VERSION]->Commit-[:AUTHORED]->Person`
+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)).

 ## Who / What / How / Where / When + evidence

@@ -80,14 +80,16 @@ Conflicting pairings (≥2 yes vs ≥2 no) = hypothesis (OQ1 → v2 resolution).
 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
-fetches Zig + libs (`bin/cgo/zig`). 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)
@@ -98,5 +100,5 @@ 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 (write, hops, corpus, agent loop): [roadmap](roadmap.md),
+Gap to v1 (hops, corpus, CI eval): [roadmap](roadmap.md),
 [epic #16](https://git.produktor.io/eSlider/2dph/issues/16).
@@ -23,8 +23,11 @@ Decisions: [PLAN.md](../PLAN.md).
 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.
-
-`POST /ingest` is a rebuild **hint**. `add` is not implemented.
+[#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).
+[#18](https://git.produktor.io/eSlider/2dph/issues/18) `--with-facts` /
+`--with-chats` on rebuild (WhatsApp out of v1).

 ## Blockers

@@ -34,24 +37,12 @@ question
    ├─ FTS + HNSW          ← in
    ├─ facts / info roots  ← in
    ├─ web (D17)           ← in
-    ├─ Cypher hop          ← #17  schema yes, search no
-    ├─ brain/add ACID      ← #14  rebuild only
-    └─ facts+chats corpus  ← #18
+    ├─ brain/add ACID      ← in
+    ├─ Cypher hop          ← in
+    └─ facts+chats corpus  ← in
 ```

-1. **[#14](https://git.produktor.io/eSlider/2dph/issues/14) write** —
-   `bin/brain/index.go --rebuild` (Python `kblib`). No incremental
-   `brain/add`. Watch/mail/git cannot become facts “now”.
-2. **[#17](https://git.produktor.io/eSlider/2dph/issues/17) hops** —
-   `Leaf-[:FROM_FILE]->File-[:HAS_VERSION]->Commit-[:AUTHORED]->Person`
-   exists; `--hop` still errors. Without a walk, D9/D10 are paper.
-3. **[#18](https://git.produktor.io/eSlider/2dph/issues/18) corpus** —
-   rebuild loads repo markdown + mail as `info`. `facts/extract` pairing
-   and `bin/chats` are not indexed. WhatsApp is a stub. PII stays in `var/`.
-4. **[#15](https://git.produktor.io/eSlider/2dph/issues/15) lever/loop** —
-   2dph is the lever (`search` → `get` → `audit`). PicoClaw is the loop.
-   Document the contour in-repo; CPU turns need a large context window.
-5. **[#19](https://git.produktor.io/eSlider/2dph/issues/19) CI eval** —
+1. **[#19](https://git.produktor.io/eSlider/2dph/issues/19) CI eval** —
   recall SoT should be `bin/brain/eval.go` via Zig, not Python `bin/kb/eval`.

 ## Not v1
@@ -61,7 +52,5 @@ contradiction resolution, OQ3 duckdb-md export, OQ4 YAML-first leafs.

 ## Close epic #16 when

- facts+info can be written without a full rebuild for every leaf
- `--hop` stops erroring and runs a Cypher path from search hits
- ops pairing + chat import land as leafs on rebuild
 - MCP tool order is documented and still gated by tests
+- CI recall SoT is `bin/brain/eval.go` via Zig
@@ -43,18 +43,20 @@ That binds `127.0.0.1:8888`. JSON format must stay enabled.

 ## Index then search

-Write path is Compose profile `index` (Python Ladybug rebuild) until
-`brain/add` is v2. The operator command is `bin/brain/index.go`.
+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/index.go --rebuild
+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/get.go <id> --body
 bin/brain/stats.go
 ```

-`--hop` is not implemented. Empty web results are `throttled`, not absence.
+`--hop N` walks File → Commit → Person from each hit. 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 =
@@ -7,6 +7,8 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"os/exec"
+	"path/filepath"

 	"github.com/eSlider/2dph/internal/brain/rank"
 )
@@ -137,13 +139,23 @@ 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",
-		"command": "bin/brain/index.go --rebuild",
-		"add":     "v2",
+			"mode":    "add",
+			"command": "bin/brain/add.go",
+			"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 {
 	switch n := v.(type) {
@@ -6,7 +6,7 @@ import (
 	"strings"
 )

-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] [--json] [--no-web]
       bin/brain/search.go serve [port]
       bin/brain/search.go --list-model`

@@ -15,6 +15,7 @@ type Options struct {
 	Root      string
 	Repo      string
 	Limit     int
+	Hop       int
 	JSONOut   bool
 	ListModel bool
 	NoWeb     bool
@@ -22,8 +23,6 @@ type Options struct {

 // 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
@@ -52,7 +51,15 @@ func ParseArgs(args []string) (Options, error) {
 			}
 			opt.Limit = n
 		case "--hop":
-			return opt, fmt.Errorf("--hop is not implemented yet (needs File/FROM_FILE edges)")
+			i++
+			n, err := strconv.Atoi(args[i])
+			if err != nil || n < 1 {
+				return opt, fmt.Errorf("--hop must be a positive integer, got %q", args[i])
+			}
+			if n > 3 {
+				return opt, fmt.Errorf("--hop max is 3 (File → Commit → Person)")
+			}
+			opt.Hop = n
 		case "--json":
 			opt.JSONOut = true
 		case "--no-web":
@@ -7,3 +7,30 @@ const FTSStmt = "CALL QUERY_FTS_INDEX('Leaf', 'id', $q) " +

 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 $n"
+
+// HopStmt is the Cypher walk from a search hit. Depth 1 = File, 2 = Commit, 3 = Person.
+func HopStmt(depth int) string {
+	switch depth {
+	case 1:
+		return "MATCH (l:Leaf {id:$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 ""
+	}
+}
@@ -7,6 +7,13 @@ import (
 	"strings"
 )

+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"`
@@ -15,6 +22,7 @@ type Hit struct {
 	Source  string    `json:"-"`
 	Score   float64   `json:"score"`
 	Snippet string    `json:"snippet,omitempty"`
+	Hops    []HopNode `json:"hops,omitempty"`
 }

 // rrfK dampens the contribution of low ranks; same constant as kblib.py.
@@ -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
-// here (needs File edges); it must still fail closed instead of changing q.
+// query, so `search "q" --hop 1` searched for "q 1". --hop must stay a flag.
 func TestParseHopIsNotSwallowedIntoTheQuery(t *testing.T) {
-	_, err := ParseArgs([]string{"what runs on arc-2", "--hop", "1"})
-	if err == nil {
-		t.Fatal("expected --hop to error (not implemented), not be swallowed")
+	opt, err := ParseArgs([]string{"what runs on arc-2", "--hop", "1"})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
 	}
-	if !strings.Contains(err.Error(), "--hop") {
-		t.Fatalf("error should name --hop, got %v", err)
+	if opt.Query != "what runs on arc-2" {
+		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")
 	}
 }

@@ -56,6 +56,12 @@ func runSearch(args []string) int {
 		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 {
@@ -108,6 +114,44 @@ func searchHits(query, root, repo string, limit int) ([]Hit, error) {
 	return rank.RankAndFilter(fts, vec, root, repo, 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 {
 	if err != nil {
 		return 1
@@ -188,6 +232,7 @@ type jsonHit struct {
 	Root    string         `json:"root"`
 	Score   float64        `json:"score"`
 	Snippet string         `json:"snippet,omitempty"`
+	Hops    []rank.HopNode `json:"hops,omitempty"`
 }

 func toJSONOut(hits []Hit, query, rootFilter string, web *rank.SecondSource) *jsonOut {
@@ -199,6 +244,7 @@ func toJSONOut(hits []Hit, query, rootFilter string, web *rank.SecondSource) *js
 			Root:    h.Root,
 			Score:   h.Score,
 			Snippet: h.Snippet,
+			Hops:    h.Hops,
 		}
 	}
 	return &jsonOut{
@@ -222,6 +268,18 @@ func resultsToDicts(hits []Hit) []any {
 		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
@@ -144,7 +144,15 @@ 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)
 	}
@@ -11,6 +11,7 @@ import (
 	"context"
 	"encoding/json"
 	"errors"
+	"io"
 	"log"
 	"net/http"
 	"os"
@@ -27,7 +28,7 @@ type API interface {
 	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:
@@ -116,6 +117,24 @@ 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)
 }
@@ -191,12 +210,31 @@ 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",
-		"command": "bin/brain/index.go --rebuild",
+			"mode":    "add",
+			"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 {
 	if env := os.Getenv("KB_SEARCH_CMD"); env != "" {
@@ -1,6 +1,7 @@
 package httpapi

 import (
+	"bytes"
 	"context"
 	"encoding/json"
 	"net/http"
@@ -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) {
-	return []byte(`{"mode":"rebuild","command":"bin/brain/index.go --rebuild"}`), nil
+func (f *fakeSearcher) Ingest(_ context.Context, body []byte) ([]byte, error) {
+	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 {
@@ -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 {
@@ -47,7 +47,15 @@ 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"},
+		},
+	},
 	{Path: PathOpenAPI, Method: "get", ID: "openapi", Summary: "OpenAPI 3 document for this server"},
 }

@@ -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) {
@@ -26,14 +26,14 @@ second independent source when local roots cannot confirm. An answer is
 bin/brain/search.go "Matrix federation"                # pointers + snippets, YAML
 bin/brain/search.go "onlyoffice postgres" --root facts # restrict to confirmed
 bin/brain/search.go "where is cs-lexicon" --json | yq '.[].ref'
+bin/brain/add.go --text T --root facts --source "a.md x b.md"
 bin/brain/get.go <id> --body                           # full chunk only when needed
 bin/brain/stats.go                                     # index health
 bin/brain/eval.go                                      # recall@5 >= 0.95 gate (Go; Python bin/kb/eval is CI fallback)
 ```

-`bin/kb/search` is a deprecated wrapper. `--hop` errors (schema has
-`FROM_FILE`; search does not walk it yet, [#17](https://git.produktor.io/eSlider/2dph/issues/17));
-do not treat it as a graph walk.
+`bin/kb/search` is a deprecated wrapper. `--hop N` walks
+`FROM_FILE` / `HAS_VERSION` / `AUTHORED` from each hit (1=File, 3=Person).

 ## Rules

@@ -8,4 +8,4 @@ Serve: `bin/brain/serve.go` (`GET /openapi.json`, `POST /mcp`).
 - `get` — read one leaf by id
 - `stats` — index health
 - `audit` — facts confidence histogram
- `ingest` — rebuild hint (write is v2)
+- `ingest` — add a leaf without rebuild
Author	SHA1	Message	Date
eSlider	4f17b8e5ab	feat: index facts extract and chats markdown on rebuild. Tests / Test (push) Skipped Tests / Release (semver) (push) Skipped Tests / Test (pull_request) Failing after 5s Details Tests / Release (semver) (pull_request) Skipped Details --with-facts / --facts-json write root=facts leafs; --with-chats picks up var/chats/md as info. WhatsApp sync stays out of v1 (Gitea #18).	2026-08-14 10:54:46 +01:00
eSliderandGitHub	a88dbb490c	feat: search --hop walks FROM_FILE to Person. (#30 ) Tests / Test (push) Failing after 4s Details Tests / Release (semver) (push) Skipped Details Parser no longer errors; hop 1 returns File, hop 3 reaches Person. Rebuild writes Leaf-[:FROM_FILE]->File so the walk is not empty on a fresh index (Gitea #17).	2026-08-14 10:51:35 +01:00
eSliderandGitHub	9d1a3f3c70	feat: write leafs incrementally without rebuilding the graph. (#29 ) Tests / Test (push) Failing after 4s Details Tests / Release (semver) (push) Skipped Details Ladybug 0.19 stays FTS/HNSW queryable on MERGE of new ids; DROP INDEX was the fatal path. bin/brain/add.go and POST /ingest land facts+info in one transaction so watch/mail/git can become leafs now (Gitea #14).	2026-08-14 10:46:59 +01:00
eSliderandGitHub	8b5be9b659	docs: record v1 detective epic and remaining gaps. (#28 ) Tests / Test (push) Failing after 4s Details Tests / Release (semver) (push) Skipped Details Read path and MCP are in; write, hops, corpus, and CI eval are still open. Board is Gitea epic #16.	2026-08-14 10:32:19 +01:00