mathiasandClaude Sonnet 5
0f932d8f77
Round-2 review found a third bypass: checkClaimEnvelope required old_str to be fully contained within the extracted frontmatter block (which excludes both "---" fence lines). An old_str disambiguated across the closing fence into the body — a natural choice, since notes.Edit requires old_str to be unique — failed that containment test, so the gate skipped validation entirely while notes.Edit applied the replace verbatim, reaching the same invalid-enum outcome as the two bypasses already closed. Remove the containment gate structurally instead of patching another edge: checkClaimEnvelope now always computes the post-edit doc and validates its resulting frontmatter, regardless of old_str's textual relationship to the fence. A body-only edit leaves the frontmatter unchanged (still valid, since the note started valid), so this is a no-op for the common case and fail-closed for every case that touches the envelope, however old_str is phrased. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>