Log a unit of work when you finish something meaningful. Capture the WHY and any open loops — git already has the diff.

Record an architecturally consequential decision (ADR-style). Only call when a real choice was made.

Report the outcome of a test/verify run (counts, not full logs).

Link a pull request to this project's work log.

Upsert the current status of a work item (feature/task). Overwrites the item's status; also records the change.

Sync a long-form project document (plan/spec/progress/runbook/research) as rendered markdown. Upserts by (kind, key); the version bumps each sync. Use for docs an agent maintains in-repo, so the log carries their current state.