## set_language_mode()

Configures the voice agent to understand and respond in additional languages beyond English. The agent starts in the primary language and switches to a secondary language when the caller requests it or speaks in that language.

### Signature

```
call.set_language_mode(
    primary: Language = "english",
    secondary: list[Language] | None = None,
)
```

| Parameter | Type | Default | Description |
| --- | --- | --- | --- |
| primary | Language | "english" | The language the agent starts the conversation in. |
| secondary | list[Language] | None | Additional languages the agent can switch to when the caller requests them. |

The `Language` type is defined as:

```
Literal["english", "spanish", "french", "german", "italian"]
```

**Return value:** `None` / `Promise<void>`

### Example: single secondary language

```
@agent.on_call_start
def on_call_start(call: guava.Call):
    call.set_persona(organization_name="Harper Valley Property Insurance")
    call.set_language_mode(primary="english", secondary=["spanish"])
    call.set_task(
        task_id="intro",
        objective="Answer questions regarding property insurance policy."
    )
```

### Example: multiple secondary languages

```
call.set_language_mode(
    primary="english",
    secondary=["spanish", "french", "german"]
)
```

### Transcript behavior

- There is no auto-translation on the transcript. Each turn appears in the language it was spoken in — if the caller speaks Spanish, that turn is in Spanish; if they speak English, that turn is in English.
- There is currently no per-turn language marker in the transcript.

### Edge cases

- If `secondary` is `None` or empty, the agent operates in `primary` only (the current default behavior).
- When a non-English language is detected during a call, the system automatically switches to a language-specific TTS voice.
- The `grace` voice has clones for Spanish, French, German, and Italian. If no dedicated clone exists for a voice + language combination, the base voice is used.

Compliance: English and Spanish are currently supported for HITRUST / PCI-compliant deployments. All languages other than English and Spanish are not. Support for other languages is planned.