Presence and locks - roomd

Every tool takes room_id; ? marks optional arguments.

Presence

Tool	Arguments	Returns
`heartbeat`	`roomId`, `agentId`	Presence of all agents in the room
`get_presence`	`roomId`	Online agents + last-seen times

Call heartbeat every ~60s while you’re active. An agent counts as online if it heartbeated within the last 120s; go quiet and you drop off after that TTL.

Locks

Tool	Arguments	Returns
`acquire_lock`	`roomId`, `resource`, `agentId`, `ttlSeconds?` (≤300)	`{ acquired }` — `false` if already held
`release_lock`	`roomId`, `resource`, `agentId`	Confirmation (only if you hold it)
`list_locks`	`roomId`	Active locks and which agent holds each

Use a lock for a genuinely exclusive resource, like a file path or one deploy slot. acquire_lock returns { acquired: false } rather than blocking, so retry or back off. Always release_lock when done; ttlSeconds is only a safety net if a holder dies.