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Function: buildFallbackChain()

buildFallbackChain(excludeProvider?): FallbackProviderEntry[]

Defined in: packages/agentos/src/api/generateText.ts:476

Auto-discovers available LLM providers from well-known environment variables and builds an ordered fallback chain.

Each entry in the returned array contains a provider identifier and an optional cheap model suitable for fallback use. Providers are ordered by general availability and cost-effectiveness:

  1. OpenAI (gpt-4o-mini)
  2. Anthropic (claude-haiku-4-5-20251001)
  3. OpenRouter (default model)
  4. Gemini (gemini-2.5-flash)

Parameters​

excludeProvider?​

string

Provider to omit from the chain (typically the primary provider that already failed).

Returns​

FallbackProviderEntry[]

An array of { provider, model? } entries ready for use as GenerateTextOptions.fallbackProviders.

Example​

// Primary is anthropic — build fallback chain from remaining providers
const chain = buildFallbackChain('anthropic');
// => [{ provider: 'openai', model: 'gpt-4o-mini' }, { provider: 'openrouter' }, ...]