Sell speech

This page is for a provider that turns text into audio. It tells you which path to use, what your upstream must answer, and how to register and quote the deployment. Quote a media model has the features and the prices.

Choose a path

The rest of this page is for the reference agent. It reads these routes from your upstream.

Give the agent this route

The agent calls POST {base}/audio/speech with Authorization: Bearer <key>. Set {base} in LIQUID_UPSTREAM_BASE_URL.

{
  "model": "acme-tts-1",
  "input": "The auction is open.",
  "voice": "alloy",
  "response_format": "mp3",
  "speed": 1.0
}

input is the last user turn. response_format and speed are present only when the buyer set them. The agent sends instructions only if you declared speech.instructions.

Answer with the audio file as the body, not JSON. Set Content-Type to the type of the file, for example audio/mpeg. The buyer gets that type. If you send none, the agent uses the type of the format that was asked for, or audio/mpeg. An empty body fails the job.

Declare the controls

• speech.instructions: the buyer's style line. The first-party OpenAI adapter declares it for a model whose name contains gpt-4o.
• speech.turns: a clip with more than one voice. No first-party adapter declares it, because they speak one voice for each clip. To sell it, write your own agent. The dispatch holds a list of turns. See Speech.

Register and quote

Register the deployment with kind set to audio_speech. List the voices and formats that it makes. Register deployments has the fields.

Quote one output_speech line in pricing. The charge is that rate multiplied by the characters of the text of all turns. The exchange counts them before dispatch, so the price cap is exactly the charge. Your upstream reports no count, and the agent meters the characters that it received.

To price a quality apart, add a line with variant {"quality": "hd"}. A request that states quality pays the line whose variant it matches. A request that states none, or a name that you do not price, pays the line with no variant. See Quote a media model.

Limits

• Speech does not stream. The agent reads the whole file, then sends it as one clip.
• A request for a voice or a format that you did not list goes to another offer before the award.
• A failed call ends the attempt. The exchange charges nothing and tries the next offer.