Reference · GlossaryFallback modelBackup model when primary fails rate limits or errors — often smaller/cheaper.On this pageWhen to useWhen not toExample#When to useWhen designing, debugging, or explaining AI systems that mention this term in docs or code.#When not toWhen a simpler term (prompt, chat, search) is enough for your audience.#ExampleSee the linked lesson for an interactive walkthrough.Learn by doing → Learn by doing →Related termsCircuit breakerModel routing← All terms