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# send_fax

> Send a fax document on a call.

[faxaction]: /docs/server-sdks/reference/python/relay/actions

[calling-call-fax]: /docs/server-sdks/reference/python/relay/call#events

[call-events]: /docs/server-sdks/reference/python/relay/call#events

Send a fax document on the call. The document must be accessible via URL.
Returns a [`FaxAction`][faxaction] that you can
use to stop the fax or wait for it to complete.

> **Info**
>
> This method emits [`calling.call.fax`][calling-call-fax] events. See [Call Events][call-events] for payload details.

## **Parameters**

**`document`** `str` — required

URL of the document to fax (PDF or TIFF format).

---

**`identity`** `str | None` — default: None

Caller identity string (TSI) transmitted with the fax.

---

**`header_info`** `str | None` — default: None

Header text printed at the top of each fax page.

---

**`control_id`** `str | None` — default: None

Custom control ID. Auto-generated if not provided.

---

**`on_completed`** `Callable[[RelayEvent], Any] | None` — default: None

Callback invoked when the fax operation completes.

---

## **Returns**

[`FaxAction`][faxaction] -- An action handle with
`stop()` and `wait()` methods.

## **Example**

```python {13}
from signalwire.relay import RelayClient

client = RelayClient(
    project="your-project-id",
    token="your-api-token",
    contexts=["default"],
)

@client.on_call
async def handle_call(call):
    await call.answer()

    action = await call.send_fax(
        document="https://example.com/invoice.pdf",
        identity="+15559876543",
        header_info="Invoice #12345",
    )
    event = await action.wait()

    fax_result = event.params.get("fax", {})
    print(f"Fax sent: {fax_result.get('pages', 0)} pages")
    await call.hangup()

client.run()
```