Record a change to a codebase entity.

Call this immediately after making any meaningful change. The event is written to the local SQLite store and returned with its assigned id and timestamp. If the reasoning fails the quality validator (empty, too short, or a generic placeholder), the result includes a warnings array — the event is still stored.

On validation failure (invalid change_type, missing entity_path) the result is {"status": "error", "error": "..."} with no event written.

Get change history for a codebase entity, newest first.

Supports prefix matching — e.g. 'users' returns all events for the users table and any users.* column.

Most recent change to an entity — what changed, when, who, why.

Like git blame but for semantic entities (DB columns, functions, env vars, dependencies) and AI agents. If no history exists for the entity, returns {"error": "..."} with protocol-level isError: false.

Filtered change history across all entities, newest first.

Combine since, entity_path, project, and changeset_id to scope the result. On unparseable since input the response is [{"error": "..."}] so the caller sees the problem.

All events that share a changeset_id, oldest first.

Use to reconstruct the full scope of a feature or task across multiple entities. If the changeset has no events, returns [{"error": "..."}] so the caller can distinguish "unknown changeset" from "empty history."

Full-text search across entity paths, diffs, reasoning, and agents.

Useful for questions like 'what changes were made for the billing feature?', 'which columns were added by cursor?', or 'show everything related to authentication'.