SessionStart

Fetches the handoff brief and returns it as additional context, before the agent reads a file.

UserPromptSubmit

Logs the prompt and checks in, so peers see the change of direction.

PostToolUse

Logs edits, commands and failures. Ships transcript deltas once enough has accumulated.

PreCompact

Forces a transcript ship and a checkpoint — the moment context is otherwise lost for good.

SessionEnd

Closes the session, releases claims, and flushes anything spooled.

get_handoff_brief

What earlier agents did before you. Call it first on any project you have not worked on this session.

search_agent_history

Search what earlier agents actually said — their reasoning, what they tried, the errors they hit.

read_transcript_window

Read the conversation around a search hit. A matching paragraph alone is rarely enough to act on.

check_in

State what you are doing, see who else is here, claim files, and hear about collisions.

list_active_agents

Who is working on this project right now and what each has claimed.

post_notice

Tell the other agents something they need to know now.

log_agent_event

Record a decision, a dead end or a blocker so the next session inherits it.

POST /api/v1/relay/events

Batch append to the session log. Idempotent on a client event id, so a spool replay is free.

POST /api/v1/relay/checkin

Heartbeat, delta, claim renewal and conflict report in one call.

GET /api/v1/relay/handoff

The brief. Add format=markdown to pipe it straight into an agent.

GET /api/v1/relay/search

Hybrid search across the conversation and the event log.

POST /api/v1/relay/transcripts

Ship a chunk of transcript. Incremental — the response says where to resume.

GET /api/v1/relay/stream

Server-sent events: backfill, then live, across every agent on a project.

GET /api/v1/relay/agents

The live roster for a project.

Every endpoint takes a bearer token: a relay key for hooks and machines, or an OAuth token carrying the relay:read and relay:write scopes for connectors.