Step-by-step answer
Stretch 45–60 min6 stepsSpecify and test the retrieval hand-off
The ingest-to-retrieval contract as frozen Pydantic models whose validators enforce the rules a consumer relies on (unique, prefixed, content-derived block IDs; evidence pages that exist; ready events only for current documents), plus three events and an in-memory index that consumes them. After a newer official copy arrives, the index never returns the old one as current, even if its ready event is redelivered late.
Back to the exercise