kb-postmortem — post-publish ingest retrospective (report-only)

After a source publishes, turn the manual "lessons learned" pass into a standard step: deterministic proxy metrics + digest deviations + backlog delta → one report. Recommendations only — every follow-up action (skill-evolve, gate edits, proposals-resolve --apply) is decided by the human. Project truth: AGENTS.md.

1. Triggers / Non-triggers

• Triggers: "postmortem <source>", "复盘这次入库", "how did this ingest go", "ingest retrospective / review this book's ingest".
• Non-triggers (never fire):
  • "run a KB QA / audit coverage / spot-check evidence / run the Q-chain" → kb-qa.
  • "semantic health check / contradictions / L4 / Q2 added value" → wiki-lint-semantic.
  • "distill this failure into the skill / evolve a skill / handle backlog item N" → skill-evolve (this skill only recommends it).
  • "work the review queue item by item" → kb-review.
  • the source is not published yet → finish the ingest (lint gate) first; this skill never runs mid-ingest.

2. Inputs

• source_id — must show lint/published in status.
• Proxy metrics via ingest-stats (windows, stage durations and reruns, lint failures ≈ rollbacks, pages estimate, violations by kind). Token/cost numbers are not available — never invent them.
• pipeline-workspace/staging/<src>/digest.md: the per-chapter content-routing table + logged deviations.
• The old pipeline-workspace/skill-evolution/backlog.yaml — read and snapshot it BEFORE running skill-mine: skill-mine overwrites the whole file, so mining first destroys the increment context.
• Residue in wiki/Review-Queue/ for this source.

3. Outputs

One standardized report pipeline-workspace/reports/postmortem/<src>-<YYYY-MM-DD>.md with four sections:

1. Proxy metrics (from ingest-stats; honest scope — no invented token/cost data).
2. Digest routing deviations (from digest.md; absent → marked degraded).
3. Backlog delta (old snapshot vs refreshed) + skill-evolve trigger recommendations (recurring signatures with count >= 2 only).
4. Gate / AGENTS.md update recommendations.

Plus a suggested-commands list: proposals-resolve dry-runs for signatures this ingest's fixes covered. Recommendations only — this skill never executes them.

4. Dependencies

• CLI: status, ingest-stats, skill-mine; proposals-resolve appears in suggestions only (human confirms and runs --apply).
• staging/<src>/digest.md (may be absent for md fast-path sources → degraded, noted in the report).
• Truth: AGENTS.md. No new LLM judgement enters the CLI.

5. Persisted artifacts

• The report pipeline-workspace/reports/postmortem/<src>-<YYYY-MM-DD>.md (the old-backlog snapshot is embedded in its delta section).
• No vault page is written; no DB row is changed (skill-mine only rewrites the derived backlog.yaml).

6. CLI commands

python scripts/pipeline.py status                                  # W1: confirm lint/published
python scripts/pipeline.py ingest-stats --source <src> --json      # W2: proxy metrics
# W3: FIRST copy/read pipeline-workspace/skill-evolution/backlog.yaml (old state), THEN:
python scripts/pipeline.py skill-mine                              # refresh (overwrites backlog.yaml)
# suggested only — never auto-run by this skill:
python scripts/pipeline.py proposals-resolve --signature <kind> --source <src>   # dry-run first

7. Workflow

8. Failure stops / recovery

• Source not lint/published → stop and point to the finishing gate (lint) or kb-review for pending violations.
• ingest-stats exits non-zero → stop, report the error verbatim.
• digest.md missing (md fast-path source) → do not stop; mark the deviations section degraded.
• Never run proposals-resolve --apply, skill-adopt, or any vault/DB write from this skill.
• Recovery: the report is idempotent — re-running the retrospective overwrites the same day's file.

9. Acceptance criteria

• Report exists at pipeline-workspace/reports/postmortem/<src>-<YYYY-MM-DD>.md with the four sections.
• The old backlog was snapshotted before skill-mine ran (the delta section shows old vs new).
• Zero vault writes, zero DB changes; proposals-resolve appears only as suggested dry-run commands.
• skill-evolve recommendations name only recurring signatures (count >= 2).