Where a proposal stands: pending, applied, declined, or expired. Needs only read access. Every field is always present; the timestamps, applied_version_uuid and decline_reason are null until that event happens. A pending proposal past expires_at is reported as expired from the clock.

An unknown uuid and a proposal on a diagram this token cannot see return the same 404. Supports ETag conditional requests, so a poll returns 304 Not Modified until something changes.

Rate limit: 60 requests/minute per token, shared with the other reads.