Providers and capabilities

Capabilities are versioned metadata, not promises of parity. list_transcription_models is the runtime source of truth for the deployed version.

Model URL input Diarization Timestamps Styles Hints
Microsoft MAI-Transcribe-2 Yes Yes none, segment, word clean, verbatim Yes
ElevenLabs Scribe v2 Yes Yes none, segment, word clean, verbatim Yes
Groq Whisper large v3 Yes No none, segment, word verbatim prompt
Groq Whisper large v3 turbo Yes No none, segment, word verbatim prompt

Microsoft requires a Speech resource endpoint and key. OpenTranscribe calls the synchronous Fast Transcription REST endpoint with enhanced mode. ElevenLabs calls /v1/speech-to-text with zero retention enabled by default. That provider option requires an eligible account; operators who deliberately accept provider-side logging may set OT_ELEVENLABS__ZERO_RETENTION=false. Groq uses the OpenAI-compatible audio transcription endpoint and supports either URL passthrough or an explicitly requested proxy upload.

Groq word timestamps are requested together with segment timestamps so word data remains attached to canonical segments instead of producing a structurally incomplete response.

The default request asks for diarization and clean output. It will not route to Groq under strict capability negotiation. To use Groq explicitly, set diarization=false and transcript_style=verbatim.

Pricing metadata lives in config/pricing.yaml. It is informational and deliberately separate from adapter code. Expired or unavailable metadata produces warnings.