> ## Documentation Index
> Fetch the complete documentation index at: https://developers.telnyx.com/llms.txt
> Use this file to discover all available pages before exploring further.

# dev

```bash theme={null}
telnyx-acp dev
telnyx-acp dev --port 8790 --no-watch
```

| Flag | Meaning |
| - | - |
| `--no-watch` | Do not reload on file changes. |
| `--port <n>` | The local port, 8787 by default. |

On a configuration project, `dev` runs the managed loop in process on a loopback listener. `instructions.md`, `agent.json` and the tools file when `agent.json` points at one are watched and reloaded on save, a `set` from another terminal included. With `web` set as `dev` starts, the chat page is served at `http://127.0.0.1:8787/web`; the page's title, greeting, number and voice button are read as `dev` starts, so a `web` or `phone` change needs a restart, and so does an edit to `.env`. On an agent with a number or `voice` settings that page has a voice button: the dev listener answers a WebSocket on the conversation's path, runs the agent's voice loop (the greeting, `voice.bargeIn`, `keypressInterrupts`, `stt` and `tts` from agent.json, Telnyx recognition and synthesis with the same credentials as the model) and journals each exchange into the conversation; one line per turn is printed here. The local loop waits for the confirmed end of turn and runs the direct engine, so `voice.eager`, `voice.filler` and `voice.harness` apply only on a deployed call. `invoke`, `chat` and `rpc` reach the listener with `--local`; `dev` records where it listens in `.telnyx/dev.json`, which `--local` reads, so those run in the same project directory. `dev` needs a session or `TELNYX_API_KEY` in `.env` to reach the model, and the `--local` callers need no sign-in. It admits one `dev` per project.

On a code-based project, `dev` writes `.telnyx/` as `deploy` would and hands over to `telnyx-edge dev`, the local actor stack in Docker, with the class reloaded on save. That stack keeps running after Ctrl-C; `docker compose -f .telnyx/dev/compose.yaml down` stops it.

Calls on a phone number, texts, email and memory need a deploy; the page's voice button is the one way to speak to the agent locally. [Local Development](/docs/agents/local-development) has what runs where and what works locally.