Vercel AI SDK — ai-lcr Docs

lcr("...") drops into every Vercel AI SDK call — generateText, streamText, generateObject, tools, and the Agent loop — unchanged.

lcr("...") returns a standard AI SDK LanguageModel, so it drops into every AI SDK call: generateText, streamText, generateObject, streamObject, tool calling, and the Agent loop.

import { streamText } from "ai";

const result = streamText({
  model: lcr("smart"),       // routed + fallback, same API
  messages,
  tools,                     // tool calling unaffected
});

Because the routed model implements the same interface, streaming, structured output, and tools all keep working — a failover mid-stream is transparent to your code. See Migrate from plain AI SDK for the before/after on an existing call site.