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Convert a chat message to speech and stream the audio. Audio is generated via our TTS provider on first request and cached automatically — subsequent requests are served from cache with no added latency.
The response is raw PCM audio: 32-bit float, little-endian, mono, 44100 Hz. You will need to decode it before playback. See the Playback section below for browser and mobile examples.

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Request

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Authorization
string
required
Bearer token obtained from the authenticate endpoint.
​
message_id
string
required
ID of the chat message to synthesize. The message must belong to your organization.

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Response

Returns a streaming application/octet-stream body of raw PCM audio.
PropertyValue
EncodingPCM float32, little-endian
Sample rate44100 Hz
ChannelsMono

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Playback

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Browser (Web Audio API)

async function playMessageAudio(messageId, token) {
  const response = await fetch(
    `https://api.trellis.sh/v1/tts/messages/${messageId}/audio`,
    { headers: { Authorization: `Bearer ${token}` } }
  );

  const pcmBuffer = await response.arrayBuffer();
  const audioCtx = new AudioContext({ sampleRate: 44100 });

  // Decode raw float32 PCM
  const float32 = new Float32Array(pcmBuffer);
  const audioBuffer = audioCtx.createBuffer(1, float32.length, 44100);
  audioBuffer.copyToChannel(float32, 0);

  const source = audioCtx.createBufferSource();
  source.buffer = audioBuffer;
  source.connect(audioCtx.destination);
  source.start();
}

​
React Native (Expo AV)

import { Audio } from "expo-av";
import * as FileSystem from "expo-file-system";

async function playMessageAudio(messageId, token) {
  const localPath = FileSystem.cacheDirectory + `${messageId}.pcm`;

  await FileSystem.downloadAsync(
    `https://api.trellis.sh/v1/tts/messages/${messageId}/audio`,
    localPath,
    { headers: { Authorization: `Bearer ${token}` } }
  );

  const { sound } = await Audio.Sound.createAsync({ uri: localPath });
  await sound.playAsync();
}

curl -X GET "https://api.trellis.sh/v1/tts/messages/8f14e45f-ceea-467f-a83c-0a06b8901a45/audio" \
  -H "Authorization: Bearer YOUR_TOKEN" \
  --output message_audio.pcm

<binary PCM audio stream>