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.

Next Concrete Step

Build a minimum viable Stage 1: port coolrl's check_doc_links.py into scripts/ as librarian_check_links.py (one-file lychee wrapper), verified to run against docs/**. No JSON aggregation yet — just exit code 0/non-zero. This proves the deterministic-lint layer works on this repo before adding the custom checks (code citations, stale plans, etc.).