Events
An event is {source, type, payload, occurred_at, ...}. Every event gets a cursor (its position in the log) and a hash that covers the event before it. A producer_event_id makes a repeat a no-op. Events marked metadata.backfill are history imported when a source connects: they're in the log and in queries, but they never fire triggers.
Coordinate's own events are on the source coordinate: trigger.fired, action.succeeded, action.failed, login.*, and anything agents or triggers emit.
Queries
Each workspace has a read-only SQL replica of its log (see Searching the log). It holds no secrets, so any agent with a read token can query it.
Triggers
A trigger is a condition and actions:
{"name": "deploy-errors",
"when": {"query": {"sql": "SELECT COUNT(*) AS n FROM events WHERE type = 'vercel.deployment.error' AND recorded_at >= strftime('%Y-%m-%dT%H:%M:%SZ', 'now', '-1 hour')", "test": {"n": {"gt": 3}}}},
"then": {"webhook": {"url": "https://example.com/hooks/coordinate"}}}Event triggers check every appended event; query triggers run their SQL after every append. See Triggers and Actions.
Pollers
Some systems have no webhooks. A poller calls an API on a schedule (optionally once per row of a SQL query) and emits an event when what it sees is new or changed. See Pollers.