coorl-lost-cities/docs/plans/librarian.md

Plan: Vendor-Agnostic Librarian

Status: Design phase. AGENTS.md "Docs & Experiment Workflow" section landed in commit 09d5815 (2026-05-07). Shell script and prompt-file move not yet started. Owner: operator-driven; Claude/Codex/Gemini may execute parts. Background: A librarian subagent at .claude/agents/librarian.md already drafts research notes and surveys docs, but it is Claude-only, read-mostly, and cannot be triggered periodically. Doc placement rules also lived inside that prompt instead of AGENTS.md, so non-librarian agents never saw them.

Goal

Split documentation hygiene into two layers:

1. Authoring rules in AGENTS.md — every agent reads these on every turn, so docs land in the right place at write time.
2. scripts/librarian.sh — periodic, vendor-agnostic, never auto-applies. Catches drift that Layer 1 missed.

Layer 1 already exists (commit 09d5815). This plan covers Layer 2.

Non-Goals

• Replacing the existing librarian.md prompt content. The note-drafting prompt is reused as a Stage 2 backend; only its location moves.
• Modifying docs/archive/ or runs/archive/. Read-only forever.
• Editing code, configs, or running training/benchmarks from the librarian. Doc/memory work only.
• Any auto-apply mode. Librarian only proposes; humans (or a follow-up PR) apply.

Architecture

Three stages, run in order. Each stage is independently invocable for debugging.

Stage 1 — Deterministic lint (no LLM)

Pure shell + rg/find/small Python helpers + lychee. Output: a JSON report at runs/tmp/librarian-<timestamp>.json. Checks:

• Markdown link integrity (lychee): every [text](path) link in docs/** and README.md resolves; anchors point to real headers. Run lychee --offline --root-dir . docs/**/*.md. Precedent: ~/dev/coolrl/src/coolrl/dev/check_doc_links.py wraps the same call for the sibling repo. We can lift that wrapper as-is.
• Code-docs parity (custom; lychee does not cover this): every path/to/file.py:NN citation in docs/** resolves (file exists, line within range). These are inline prose, not markdown links, so lychee ignores them. Short Python helper required.
• Stale plans: docs/plans/*.md with mtime > N days and no recent git commit referencing them.
• Promotable archive: docs/archive/<name>-*.md with no docs/research/<name>.md counterpart, where the archive body contains durable-conclusion language.
• MEMORY.md drift: index lines in ~/.claude/projects/.../MEMORY.md that disagree with the target file's description: frontmatter.
• Duplicate prose: pairs of docs with high text overlap (e.g., a research note that copies an archive body instead of linking it).
• Oversize: files past the 500-line soft cap in AGENTS.md.

No LLM calls in Stage 1. Cheap to run frequently.

Stage 2 — LLM judgment (vendor-agnostic)

Reads the Stage 1 report and the relevant doc bodies, dispatches to an LLM CLI selected by env var:

LIBRARIAN_LLM=claude   # claude code
LIBRARIAN_LLM=codex    # codex cli
LIBRARIAN_LLM=gemini   # gemini cli

The system prompt is loaded from scripts/librarian-prompt.md (moved from .claude/agents/librarian.md; same content). LLM produces:

• Research-note drafts for promotable archive entries.
• MEMORY.md drift fixups (one-line diffs).
• Duplicate-doc merge proposals.

Output format: a unified diff + a short rationale per change. Never written to disk by the LLM directly — emitted as a patch file under runs/tmp/librarian-<timestamp>.patch.

Stage 3 — Dry-run apply (default) / human apply

Default: print the patch and exit. With --apply: git apply the patch (still requires the human to commit). Conflicts surface as standard patch failures — operator resolves manually.

docs/archive/ and runs/archive/ are filtered out of any patch target before apply.

Concurrency Policy

Librarian is never invoked from within an active agent session. It runs on demand by the operator (or via cron / post-commit hook). Because Stage 3 is propose-only by default, two parties editing the same file cannot corrupt each other — git's 3-way merge handles overlap when the operator applies the patch.

Open Questions

• Cron cadence? (start with manual-only; add cron once Stage 1 is stable)
• "Durable-conclusion language" detection in Stage 1 — keyword heuristic vs. defer to Stage 2 entirely. Default to deferring; Stage 1 just flags every archive without a research counterpart.
• Where the Stage 1 ignore-list lives once false positives accumulate. Tentatively scripts/librarian-ignore.txt with one rg-style pattern per line.

Progress

• ✅ AGENTS.md "Docs & Experiment Workflow" section landed (commit 09d5815, 2026-05-07).
• ✅ Plan drafted at docs/plans/librarian.md (this file).
• ✅ Prompt moved: .claude/agents/librarian.md → scripts/librarian-prompt.md. Claude-specific subagent registration removed.
• ✅ Stage 1, piece 1: scripts/librarian_check_links.py (lychee wrapper). Caught one stale README link on first run (commit b9bbb4f).
• ✅ Stage 1, piece 2: scripts/librarian_check_citations.py (custom file:line citation checker over inline-code spans). Skips docs/archive/ and docs/plans/archive/. Ignore list at scripts/librarian-ignore.txt for intentional future-tense references. Caught one real drift in docs/research/optimization_sequencing.md (path moved into docs/plans/archive/).
• ✅ Stage 1 orchestrator: scripts/librarian.sh. Runs every Stage 1 check in order, aggregates exit code, prints findings inline. Single entry point for users and (future) cron.
• ✅ AGENTS.md mentions scripts/librarian.sh as the doc-lint entry point in "Notes For Future Agents" (commit 0b363b5).
• ✅ Stage 1, piece 3: scripts/librarian_check_oversize.py. Flags any non-archive markdown file over the 500-line soft cap declared in AGENTS.md. Caught one real finding on first run: docs/performance.md at 914 lines — split into sub-topics deferred as a separate task.
• ✅ Stage 1, piece 4: scripts/librarian_check_stale_plans.py. Uses git log -1 --format=%cs per plan file; flags plans whose last commit is older than 60 days. Clean on first run (all four plans committed 2026-05-07).
• ✅ Stage 1, piece 5: scripts/librarian_check_memory_drift.py. Validates that every MEMORY.md index line points to a real file with required frontmatter fields (name, description, type ∈ {user, feedback, project, reference}) and that no memory file is orphaned from the index. Memory dir derived from repo root, so the script is portable. Clean on first run.

Stage 1 Status: Complete

All deterministic checks land. Two remaining concepts intentionally moved out of Stage 1 because they require LLM judgment, not deterministic detection:

• Promotable archive entries → Stage 2. "Durable conclusion" detection is judgment, not pattern matching.
• Duplicate prose → Stage 2. Shingled-overlap heuristics produce too many false positives in this repo's mix of archive snapshots and derived research notes; LLM should decide whether two passages are the same idea vs the same evidence.

Open Stage 1 finding to address: docs/performance.md at 914 lines.

Next Concrete Step

Address the open Stage 1 finding by splitting docs/performance.md into sub-topic notes under docs/research/ (and dated archive entries where appropriate). Sketch the split as a 1-page sub-plan before doing the actual move so we don't shred a useful document.