| name | stt |
| description | Transcribe audio files to text. Use when you need to convert speech/audio to text. |
Speech-to-Text (STT)
Transcribe audio files to text using the stt CLI.
Usage
stt /path/to/audio.wav
stt --language de /path/to/audio.ogg
stt https://example.com/recording.mp3
Supported Formats
wav, mp3, ogg, m4a, aac, flac, webm, mp4 (audio track)
Direct API Usage
The STT endpoint is Whisper-compatible (OpenAI /v1/audio/transcriptions format):
curl -X POST "$STT_URL" \
-F "file=@/path/to/audio.wav" \
-F "response_format=json" \
-F "language=de"
Response: {"text": "transcribed text here"}
The URL is resolved from: ATLAS_STT_URL env → STT_URL env → config.yml (stt.url) → default.
Limitations
- Long files (>2 min) are split into 120s chunks with 5s overlap — minor artifacts at chunk boundaries are possible
- Accuracy depends on audio quality; background noise reduces quality significantly
- The model runs on CPU (int8 quantized) — expect ~5-15s processing per minute of audio
- Single-speaker optimized; multi-speaker conversations may lose speaker attribution
- No diarization (speaker identification) — only raw text output
Signal Integration
Audio messages received via Signal are automatically transcribed before reaching the agent — no manual action needed.