end_call hangs up. It is how an agent closes a call itself — after the caller has said they are done, after a booking is confirmed, or on a branch where there is nothing left to do.
There is nothing to configure. config may be omitted entirely, and an end_call with any field in it is refused at save.

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Everything the tool must do goes before it

end_call is terminal in its chain. Nothing may follow it in the top-level list or inside a then/else branch, and saving a tree that puts an operation after one is rejected:
That is not a formatting rule. By the time end_call returns, the session is draining: an HTTP call to log the outcome, a POST that files the lead, a set_variable that stamps userdata — all of it has to be above the end_call, while there is still a call to do it on.

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Wording the goodbye

Put a say immediately before the end_call if the caller should hear something. Word it as what actually happens: the call ends here.
Never say “let me transfer you”, “please hold” or “someone will call you back” before an end_call. The caller hears a promise and then silence, and they will call back angrier than they left.If you want a transfer, use the transfer operation — there, “let me put you through” is a promise the platform keeps. If someone really will call back, say so only if something in the same tree actually files that request.
You do not need wait_for_playback on that say. end_call waits for everything outstanding — the model’s own speech from before the tool ran, and the goodbye the tree queued — before it hangs up, and the agent never says anything after it. Ticking the flag adds nothing and can only slow the tree down. (The wait is bounded: if a text-to-speech provider stalls for 60 seconds, the call is ended anyway rather than hanging.)

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The agent says nothing afterwards

A tool run that reaches end_call tells the model nothing at all, whatever the tree collected on the way. There is nobody left to narrate it to, so the model is not given a chance to add a sentence to a call that is already over. That also means silent is irrelevant on a tool that ends the call — it is already silent by the time it matters.

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How the call is recorded

user_initiated names whichever side called shutdown, which on this platform is only ever the end_call operation. It means the agent hung up, not the caller. A caller hanging up is participant_disconnected. See close reasons.
A call ended this way is a completed call: it is billed the platform fee, it is eligible for post-call analysis, and its recording is kept under the usual retention.

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Worked example: qualify, then close

An outbound qualification tool that files the answer and ends the call on one branch while carrying on with the conversation on the other. Note that the whole “keep going” path lives in the else — branches do not rejoin, so there is no place after the if to put shared work.
Do not use end_call as an error handler. A tool whose HTTP call failed should usually let the agent apologise and carry on; hanging up on a caller because your API returned a 500 is the worst available outcome. Use on_error on the failing operation instead — see the operation tree.

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Next

Transfer

Handing the caller to a person instead of hanging up on them.

Speech operations

say, generate_reply and when a line needs wait_for_playback.

Close reasons

Every reason a call can end, and what each one means.