# Telephony

URL: /systems/communications/phone · Id: `capability:phone`

> Telephony places and answers voice calls and sends text messages from a Startup’s numbers, honoring Consent and opt-outs.

Telephony places and answers voice calls and sends text messages from a [Startup](/business/nouns/startup)'s own numbers. Every call and text honors [Consent](/business/nouns/consent) and opt-outs.

## Contract
- Each number is a [Channel](/business/nouns/channel) that routes to a [Worker](/business/nouns/worker), a voice [Agent](/business/nouns/agent) or a person, or to a [Workflow](/business/nouns/workflow).
- A voice Agent answers live and transfers a call to a person with the transcript so far.
- Every call and text is a [Message](/business/nouns/message). A call keeps its recording and transcript; texts thread by number.
- A call records only after the caller hears the notice their region requires.
- Consent for the [Purpose](/business/nouns/purpose) is checked before any marketing call or text.
- A reply of `STOP` adds a [Suppression](/business/nouns/suppression) at once, and `HELP` returns the Startup's contact details.
- Marketing texts send only between 8 a.m. and 9 p.m. in the recipient's time zone.
- Transcription runs through the [AI gateway](/code/platform/ai-gateway). Numbers come from [Phone numbers](/systems/communications/phone-numbers).

## Verbs
| Verb | Object | Event |
| --- | --- | --- |
| [Message.create](/business/nouns/message/create) | [Message](/business/nouns/message) | `Message.created` |

## Interfaces
- [API](/code/api/reference)
- [SDK](/code/sdk/reference)
- [CLI](/code/cli/reference)
- [MCP](/code/mcp/reference)

## Example
```ts
// fixpoint.co books appliance repairs. Every booking gets a confirmation text from the main line.
import { $ } from 'startup-builder'

await $.Message.create({
  medium: 'sms',
  direction: 'outbound',
  from: 'channel_main_line',
  to: '+15125550142',
  purpose: 'appointment',
  body: 'Your technician arrives Thursday, 9 to 11 a.m. Reply STOP to opt out.',
})
```