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

# Expressive mode

> Prepare expressive speech deliberately and check model-specific emotion or audio-tag capabilities before authoring settings.

Expressive speech can convey a calm explanation or a welcoming greeting. Start with the words and intended tone, then check whether the selected speech model exposes a compatible control.

<Note>
  There is no universal expressive-mode switch in the agent TTS contract. Model options and expressive-audio-tag capabilities are separate. Voice publication and live expressive conversation behavior remain unavailable.
</Note>

## Choose an approach

| Approach | What to prepare |
| - | - |
| Wording | Clear sentences and a tone instruction appropriate to the agent's task. |
| Model-specific options | An option such as `emotion` only when the selected model's parameter schema includes it. |
| Expressive audio tags | Tagged text only when the model reports `supports_expressive_audio_tags`. |

An emotion option does not imply support for arbitrary tags. Pronunciation dictionaries and phoneme tags are also separate capabilities; review [pronunciation](/agents-platform/configure/voice-and-language/pronunciation) when the issue is how a word sounds.

## Prepare a controlled comparison

<Steps>
  <Step title="Write the intended delivery">
    Describe a concrete result, such as a calm pace while explaining a failed payment. Avoid instructions that pressure the listener or claim emotions the agent cannot know.
  </Step>

  <Step title="Check the selected model">
    Use [Get available AI model](/api-reference/agents-platform/get-available-ai-model) to inspect its parameter schema and expressive-tag capability. Do not borrow tag syntax or option names from another model.
  </Step>

  <Step title="Save only supported settings">
    If using a model option, place it under `conversation_config.tts.options` with the matching `schema_id`. Preserve the rest of the configuration in a [server draft](/agents-platform/deploy/versioning).
  </Step>

  <Step title="Keep the listening result separate">
    Read back the requested settings, then record the listening comparison as pending until a supported speech path is available. A saved option cannot establish that the delivery sounds natural.
  </Step>
</Steps>

## Frequently asked questions

<AccordionGroup>
  <Accordion title="Can I add arbitrary stage directions to the prompt?" id="faq-expressive-directions">
    Treat tone instructions as text. Do not assume bracketed directions become audio controls; an unsupported model may ignore or speak them.
  </Accordion>

  <Accordion title="Does expressive support imply phoneme support?" id="faq-expressive-phonemes">
    No. Check each capability independently for the selected TTS model.
  </Accordion>
</AccordionGroup>


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