The key to pass to a system with a side effect (an Idempotency-Key header, a client token), so that running the same call again does not repeat the effect: the call's ToolCallInfo.idempotencyKey when it is supplied, which is the same in every run of the call.
The key to pass to a system with a side effect (an Idempotency-Key header, a client token), so that running the same call again does not repeat the effect: the call's ToolCallInfo.idempotencyKey when it is supplied, which is the same in every run of the call.
Without a ToolCallInfo it is derived from the tool's name and the call's arguments (tool- and the SHA-256 of the name and the arguments' JSON with the object keys sorted), so it is the same for equal arguments in any key order: two separate calls with equal arguments then share a key, and a system that honours it runs the second as a repeat of the first.