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Phone Numbers

Phone numbers are the entry point for calls into VOCALS. Each number is connected via a SIP provider and assigned to an agent that handles all calls to that number.

Setting Up a SIP Provider​

Before assigning phone numbers, you need to configure at least one SIP provider. VOCALS supports Twilio, Netelip, and any generic SIP trunk provider.

See the SIP Providers guide for detailed setup instructions for each provider type.

Number Format​

Every number you enter must be in E.164 format: a +, the country code, then the national number, with no other characters. VOCALS accepts spacing and punctuation while you type and stores the number tidied up, so +34 930 485 412 and +34-930-485-412 both become +34930485412.

A number without a + and country code is rejected when you save it. VOCALS never guesses the country for you: adding a country code to a national number would produce a valid-looking number in the wrong country, and calls to it would silently never arrive.

You typeStored as
+34 930 485 412+34930485412Accepted
+1 (415) 555-1234+14155551234Accepted
930485412--Rejected: no country code
872 43 27 50--Rejected: no country code

If a number saved before this rule existed is still missing its country code, calls to it will not reach an agent. Remove it from the SIP provider, add it again with the country code, and re-assign it to the agent.

How Calls Are Routed​

Caller dials number
    |
SIP provider receives call (PSTN)
    |
SIP provider routes to VOCALS via SIP trunk
    |
VOCALS orchestrator receives the call
    |
VOCALS opens a WebSocket Media Stream
    |
Real-time audio streaming begins (mulaw/8kHz)

Assigning Numbers to Agents​

Each phone number maps to exactly one agent. When a call arrives on that number, VOCALS loads the assigned agent's configuration (system prompt, providers, settings) and starts the voice pipeline.

To Change the Agent Assignment​

  1. Go to Phone Numbers in the dashboard.
  2. Click the number you want to update.
  3. Select a different agent from the dropdown.
  4. Click Save.

The change takes effect on the next incoming call. Active calls are not affected.

Multiple Numbers, One Agent​

You can assign the same agent to multiple phone numbers. This is useful when:

  • You have local numbers in different area codes that all route to the same agent.
  • You want separate numbers for tracking purposes (e.g., one number per marketing campaign) but the same conversational experience.