`[2026-07-16]` **`sortable_chunk_fields` advertised WITHOUT the required `type` field = whole-handshake deploy-breaker; only DRIVING the real bind caught it.** bifrost `handshake_response` `SortableChunkField` requires BOTH `name`+`type` (`additionalProperties:false`); we shipped `[{"name":"updated_at"}]` → the response failed wire-schema validation → `bifrost.schema_validation_failed` → the ENTIRE bind (memory+affect) broke, not just sort. Unit tests + worldtree-dev's name-only service parser + the heid-bug-hunt ALL passed it — only the live handshake drive (`/verify` discipline) caught it. **Lesson: validate `describe_store` against the bifrost WIRE schema, not just our own caps assertions.** (Sibling of the `[2026-07-10]` frozen-v0.6 handshake foot-gun — there an EXTRA field broke a v0.6 handshake, here a MISSING required field broke a v0.7 one.)
