lease

com.mcpscores/agent-continuity · Verify this server

Mutual exclusion so two instances of the same agent do not both process one item. Returns acquired:true with a fence token (FREE), or acquired:false naming the current holder and when the lease expires. ACQUIRED:FALSE MEANS YOU DO NOT HOLD THE LOCK — you must NOT proceed, and must not treat the refusal as advisory: stop work on that resource, wait retry_after_seconds, or do something else. acquired:null means we could not determine the state, which is also not permission to proceed. YOU ARE GIVEN TWO NUMBERS AND THEY DO DIFFERENT JOBS. `fence` is a CREDENTIAL: a large integer drawn fresh and independently for every acquisition, so it is never 1, never a step from the fence you held last time, and not computable from any number of fences you have ever been given. Treat it as a secret — it is the one thing that tells you apart from another instance using your holder label. `generation` is the ORDER: a counter that strictly increases on every fresh acquisition and never resets, not on expiry and not on release. It is not a secret, it is the number to compare and the number to hand to an external store that must reject stale writers. A revived holder from an earlier generation therefore cannot renew or release a lease someone else now holds — not because its number is smaller, but because it does not have the new one. RE-ACQUIRING A LEASE YOU HOLD IS A RENEWAL ONLY IF YOU PRESENT ITS `fence` — a holder LABEL is not proof, because two instances of the same agent are exactly the callers most likely to share one, and we will not hand the same lock to both. A live lease requested under its own label without the fence is REFUSED with acquired:false, same_holder_label:true and held_by, never silently renewed. A renewal keeps your fence and stays free. $0.002 is charged the first time you are refused by a given holder; being refused again by the SAME holder is free. Costs $0.002 USDC per call via x402 on Base, and ONLY when acquired === false, and this refusal by this holder has not been billed before; otherwise the same call returns the full answer and settles nothing. Authenticate with Authorization: Bearer <agent_secret>, or pass agent_key as an argument if your host cannot set headers. Equivalent HTTP route: POST /v1/lease.