Voice: phone-call agents

The Voice tab turns your agent into a phone-answering voice agent.
Inbound calls route to the phone number you provision, the agent answers
in a voice you picked, and it can handle the full conversation — bookings
and all.

Getting started

1. Provision a phone number. Click + Get a number, optionally with
2. Pick a voice. Browse 11labs voices, preview them, pick one. Common
3. Tune it. Four sliders:
4. Write the opening + closing. Supports [merge
5. Enable voice. Toggle the agent on.

How voice agents differ from chat agents

Same brain, different instructions:

• Much shorter responses. 1–3 sentences max — people don't listen to
• No markdown, no lists. Plain prose only.
• Natural speech patterns. "Uh-huh", "let me check that for you",
• Separate tool set. Some CRM tools work the same, some are

We inject voice-specific instructions into the system prompt automatically
— you don't need to rewrite your prompt for voice.

Test calls

Use Start call in the Test Call panel to dial your agent from the
browser (mic permission required). Full transcript + volume indicator
visible during the call. Great for auditioning voice tuning changes.

Recording + transcripts

Record Calls is ON by default. Recordings live on Vapi; transcripts
land in your Voxility inbox. Turn off if you're in a jurisdiction with
strict consent requirements you haven't met.

End-call phrases

Words or phrases that, when the caller says them, gracefully end the
call. Default is empty — add common ones like goodbye, thanks bye,
hang up to avoid awkward "sorry I didn't catch that" loops at the end.

Max Call Duration

Hard cap in minutes. 10 is a reasonable default; 30+ makes sense for
complex sales calls but costs more per call.

Voice Tools

The voice agent automatically uses the same tools configured on the
Tools tab, plus a handful of voice-specific ones:

• get_available_slots (voice-optimised)
• book_appointment (voice-optimised)
• tag_contact
• send_sms_followup — queues a text after the call ends

Common gotchas

• No bookings? Check the Tools tab — you need a connected calendar
• Voice sounds robotic? Lower stability to 0.3–0.4 for more expression.
• Agent talks over the caller? Turn endCallPhrases off or lengthen the