Fallback strategies

Status: implemented for LLM, STT, and TTS fallback adapters.

Use fallback providers when a model call can be retried through another configured provider.

Fallback behavior is provider-list based. Configure a primary provider, then provide ordered fallback providers for the same capability. The app layer constructs fallback adapters for supported LLM, STT, and TTS paths.

Environment variables

export RTP_AGENT_LLM_FALLBACK_PROVIDERS="openai,groq"
export RTP_AGENT_STT_FALLBACK_PROVIDERS="deepgram,assemblyai"
export RTP_AGENT_TTS_FALLBACK_PROVIDERS="cartesia,elevenlabs"

Provider names must match names supported by app.AppConfig construction. A fallback entry does not make an adapter support a capability it lacks.

What fallback does not cover

This page does not claim every LiveKit fallback recipe is implemented. Provider-specific retries, circuit breakers, and business-level fallback behavior should be documented only when source and tests cover them.

Evidence:

• core/llm/llm.go
• core/llm/fallback_adapter_test.go
• core/stt/fallback_adapter.go
• core/tts/fallback_adapter.go
• app/app.go