Lean Zettelkasten

lean-zettelkasten

Cold-tier skill — invoked explicitly by name (@lean-zettelkasten) from review and synthesis flows. No MANDATORY preamble: the gates in §Behavioural rules are advisory and reviewed at synthesis time rather than per-note. Persist is still required (FSIA-R-11-09) but is local to the docs/project/lean/docs/zettelkasten/ tree.

Routing

• USE FOR: creating a fleeting note from a council observation; creating a literature note when citing lean-pitfalls / Mathlib docs / a paper; promoting a cluster of ≥3 notes to a permanent note via the Synthesizer; bidirectional linking (Related, Contradicts, Supports, Supersedes); running orphan / island / contradiction / staleness / coverage scans; updating _index.md and _tags.md.
• DO NOT USE FOR: running the review council itself (use @lean-review-council); reviewing a specific proof (use @lean-proof-review); updating external papers from Lean results (use @lean-doc-improvement); authoring the council retro / methodology (use @lean-retro-methodology); generating a project blueprint (use @lean-blueprint).
• TRIGGERS: zettel, ZK-, fleeting note, permanent note, synthesis.

Behavioural rules (G-*)

• G-1 (MUST): Every note MUST use the ZK-YYYYMMDD-NNN ID grammar, with NNN sequential within that date. [Trace: AC-01]
• G-2 (MUST): Every note MUST declare Type, Created, Author, Source, and at least one tag. [Trace: AC-02]
• G-3 (SHOULD): Fleeting notes SHOULD remain minimal — capture the observation; do not perfect prose. [Trace: AC-03]
• G-4 (MUST): A permanent note MUST link to all source fleeting/literature notes it synthesises, and the sources MUST be marked superseded. [Trace: AC-04]
• G-5 (MUST NOT): The skill MUST NOT promote a cluster to a permanent note unless ≥3 source notes converge on the pattern. [Trace: AC-05]
• G-6 (SHOULD): The skill SHOULD propose a downstream @lean-proof-review or @lean-quality-engine skill update when a permanent note implies a methodology change. [Trace: AC-06]

Workflow

1. Discover [discover] — read the triggering event (council session, new literature citation, scheduled scan). Locate _index.md, current note counts, recent tag activity.
2. Plan [discover] — pick note type (fleeting / literature / permanent) or scan type (orphan / island / contradiction / staleness / coverage). For permanent promotion, verify ≥3 source notes (G-5). STOP if cluster size < 3 and downgrade to literature note.
3. Execute [execute] — write the note(s) under the correct directory (fleeting/, literature/, or permanent/<category>/); establish bidirectional links; flag contradictions for SDR.
4. Verify [validate] — re-check ID uniqueness, link reciprocity, tag presence (G-1, G-2). Max 3 re-checks then escalate.
5. Persist [persist] — commit the new/updated notes, update _index.md and _tags.md, and (if applicable) open a skill-update proposal for @lean-proof-review or @lean-quality-engine (G-6). Persist is local to docs/project/lean/docs/zettelkasten/.

Recovery & STOP

• Permanent-note promotion attempted with < 3 source notes → STOP, downgrade to literature note (G-5).
• Contradiction detected during synthesis → STOP this synthesis pass; emit a fleeting note flagging both sides for SDR.
• Orphan scan returns > 10 % of notes orphaned → STOP, hand off to @lean-retro-methodology for a knowledge-coverage retro.
• Confidence < 80 % on which category a permanent note belongs in (tactics/, pitfalls/, conventions/, cross-module/, proofs/) → STOP, ask.

Handoffs

• Predecessors / successors: see FM handoffs. Inbound: @lean-proof-review, @lean-review-council, @lean-retro-methodology, and @lean-proof (post-proof pattern capture) seed fleeting notes. Outbound: @lean-doc-improvement consumes permanent notes that imply paper updates; @lean-quality-engine consumes permanent notes that imply skill or methodology changes.
• Source spec: specs/lean/zettelkasten/requirements.md — every G-rule traces to an AC there.
• Related ADRs: ADR-0076 (skill-as-contract), ADR-0080 (handoff DAG), ADR-0079 (cold-tier loading rationale).

Common failure modes

AI agents commonly: over-polish fleeting notes (defeats the speed of capture); promote 1–2-note clusters to permanent notes; create permanent notes without back-linking the sources or marking them superseded; silently resolve a contradiction instead of flagging it for SDR; skip _index.md and _tags.md updates so the graph view rots. Full registry: GUARDRAILS.md §Agent failure taxonomy.

See also

• This SKILL.md is the canonical v2 zettelkasten contract for this package.
• ../../zettelkasten/_index.md — live ZK index this skill maintains.
• ../lean-doc-feedback/SKILL.md — v2 sibling on the documentation side of the DAG.