Outbound Call

Outbound Call makes a flow place a phone call. You choose one of your voice agents, the number to call and, optionally, what the agent says when the call is answered and what it should know about the call. The agent dials, lets whoever picks up say hello first, holds the conversation with its usual tools and voice and, when the call ends, the flow gets a report of it: whether it was answered, whether a voicemail picked up, and a summary. If a voicemail picks up, that is noticed within a few seconds and the agent hangs up, or leaves your message and hangs up.

The call always uses the agent’s published version and goes out through the outbound trunk chosen when publishing it. How to prepare the trunk and the agent is explained in Outbound calls.

When to use it

Reminding customers of appointments the day before and confirming or changing the time.
Confirming orders or deliveries by phone.
Running satisfaction surveys after a service.
Alerting a customer about an incident as soon as another flow detects it.

Configuration

Destination, First Message and Call Context support tool mode: that way, a text agent in the flow can decide whom to call and what to say.

Field	What it does
Voice Agent	The agent that calls: one of your flows with a Voice Agent in it. Press the refresh button to list them. It must be published and have an outbound trunk.
Outbound Line	The line the call goes out through: one of your outbound trunks. Press refresh to list them; only your account’s appear. Agent’s line (automatic) (default) uses the line chosen when the agent was published.
Destination	The number to call in international format, for example `+34600000000`, or a SIP user of the outbound line, for example `1001` or `alice`. A full SIP address (`sip:user@host`) cannot be dialled.
First Message	What the agent says once the person has said hello, word for word. Empty, it opens with its own greeting.
Call Context	What the agent should know about this call: whom it is calling, why and any details it needs. It receives it before the conversation starts.
Wait For Answer	On (default), the flow waits for the call to be answered or the attempt to fail, and the result says which. Off, the flow continues as soon as dialling starts.
Language Model	Only shown with Detect Voicemail or Summarize The Call on. Connect any language model (it enters from below): a few seconds after the answer it reads what was said for Detect Voicemail and, when the call ends, the whole call for Summarize The Call. A fast, cheap model is enough. Without a model the report has the transcript only.

Advanced options

Field	What it does
Caller Number	The number the called person sees: one of the chosen line’s numbers (press refresh) or one you type. Line’s default: one of the agent’s published numbers, or the line’s own.
Ring Timeout (Seconds)	How long the phone rings before the attempt is given up as unanswered. Default: 45.
Detect Voicemail	On (default), a few seconds after the answer the model reads what the other side said and tells a voicemail or a recorded message from a person. The agent does not wait for the check: a person notices nothing. It only hangs up when the model is sure twice in a row, 5 seconds apart, so a person who said something that could be a voicemail (“Hi, this is Marta”) has time to answer the agent. A voicemail ends the call at around 15 seconds and the flow goes on. In doubt, the call goes on as usual.
Check For Voicemail After (Seconds)	How many seconds after the answer that check is made. Leave time for the voicemail greeting to play. Default: 10 (5 to 60). Only with Detect Voicemail on.
On Voicemail	What to do when a voicemail answers: Hang up (default) hangs up at once; Leave a message and hang up says Voicemail Message and hangs up. Only with Detect Voicemail on.
Voicemail Message	The message left on the voicemail, word for word, before hanging up. Write it in the language of the person called. Only with Leave a message and hang up; empty, it hangs up without a word.
Summarize The Call	On (default), the step waits for the call to end and the model writes a summary; in production, the execution pauses while the call lasts. With this and Detect Voicemail off, the flow continues as soon as the call is answered, as before.
Wait For The Callee To Speak (Seconds)	When they pick up, people say hello first (“Yes?”, “Hello”). The agent waits for that and speaks after it; if nobody says anything in these seconds, it starts anyway. Default: 3. With 0, it speaks as soon as the call is answered.
Longest Wait (Minutes)	With voicemail detection or the summary on: if the call is still going after this long, the step finishes with what has been said so far. The call is not cut. Default: 30.

Output

The Call output holds the call’s result: its status (answered if it was answered, busy, no_answer, failed, or dialing if the flow did not wait), whether it was answered (answered), the reason when it fails the call’s ID (call_id), the line it went out through (trunk) and the number shown (caller_number). The call appears in the history as Outbound.

When the step waits for the call to end, it also holds:

Field	What it is
`ended`	Whether the call was over. `false` only if it was still going after Longest Wait.
`duration_seconds`	How long it lasted.
`hangup_reason`	How it ended: who hung up, a transfer, or why it failed.
`transcript`	The conversation, one line per turn (`Agent:` and `Callee:`).
`voicemail`	`true` if a voicemail or a recorded message answered, `false` if a person spoke or nobody answered, and empty without a model or with Detect Voicemail off. With a voicemail, `hangup_reason` is `voicemail detected`.
`summary`	A summary of the call in its language. Needs Language Model and Summarize The Call.

Whether the call was answered is the phone network’s word, not the model’s. The model only reads what was said.

You can connect the output to a component that decides what to do next, for example sending a message if nobody answered or a voicemail picked up.

In production, the execution pauses during the call

When the published flow runs in production (through the API, a webhook or a schedule) with Summarize The Call on and a Language Model connected, the flow does not sit waiting while the conversation lasts:

As soon as the call is answered, the execution pauses at Outbound Call and stops holding the server.
When the call ends (or Longest Wait passes), the same execution continues from Outbound Call with the full report and runs only what comes after it. The steps before it are not repeated: it uses their same results and nobody is called again.
In the executions log it is one execution, with the same ID: you see Outbound Call twice, first paused (paused) and then with the report (resumed), followed by the steps after it.

If you call the flow through the API and wait for the response, it arrives when the call is answered, without what comes after the step. In the playground, in tests and when the step is inside a loop or in batch mode, Outbound Call waits for the call to end as always.

Example

A clinic reminds patients every afternoon of the next day’s appointments.

A Scheduler task runs a flow every day at 18:00 that looks up tomorrow’s appointments.
For each appointment, Outbound Call with Voice Agent “Appointment reminder”, the patient’s phone in Destination and in Call Context: “Patient Ana García, appointment tomorrow at 10:30 with Dr Ruiz. Confirm or offer a change”.
With Language Model connected, once the call ends the step returns the summary (“Confirms tomorrow’s appointment at 10:30”). If a voicemail answers, with On Voicemail set to Leave a message and hang up it leaves “This is the clinic calling to remind you of your appointment tomorrow at 10:30” and hangs up within seconds.
If the call is not answered or a voicemail answers, the flow sends a message with the same information.

Good practices

Explain in the agent’s prompt that it may be the one placing the call.
A voicemail counts as answered: connect Language Model to know it through voicemail and to have the call end as soon as it is detected.
For many calls in a row, turn off Wait For Answer and check the results in the history.
Follow the rules on commercial calls: hours, consent and opt-out lists are the responsibility of the flow that calls.

Voice Agent: the agent that places the call.
Voice Agent Realtime: can also place the call.
Transfer Call: uses the same outbound trunk to pass calls to a phone.