CONTRIBUTING.md gains a "Code comments" section: comment the why not
the what, keep it to a sentence or two with a pointer to the load-bearing
evidence, don't re-derive a sibling's already-documented reasoning, and
move failed-attempt investigation logs out of inline comments.
Applied that policy across the codebase: condensed sprawling module
docstrings, per-entity essays, and multi-paragraph rationale blocks down
to their load-bearing conclusions, while preserving the actual "why"
(issue numbers, calibration evidence, gotchas, don't-guess rationale).
No functional code changed — verified via diff review, ruff, ty, and the
full pytest suite (1211 passed).
One inline investigation log (the AC filter-reset "tried and failed"
notes) moved to docs/investigations/ac-filter-reset.md rather than being
deleted, per the new guideline on where that kind of record belongs.
One commit per issue/logical change, and every commit's author and
committer must be the human accountable for the work -- never a tool,
bot, or AI agent identity, and no AI co-author trailers. AGENTS.md points
any AI coding agent working here back to CONTRIBUTING.md as the
authoritative source for this.