Purpose: provides an append-only durable event ledger. Schema: schemas/contracts/event-record.schema.json. Required: schema_version, ts, type, payload; task_id is optional. Valid/invalid examples: examples.json#/event-record.
Events are emitted for task, process, failure, checkpoint, and decision facts. Producers redact secrets; consumers treat rows as historical facts and may filter by cursor/type. Versioning/migration: provisional; do not mutate existing rows, write migration projections when necessary. Maturity: provisional.