{"record":{"id":"73f9a0587435e2a4","repo":"BerriAI/litellm","slug":"default-model-config-default-model-is-not-a-kn","errorCode":null,"errorMessage":"default_model '{config.default_model}' is not a known chat model","messagePattern":"default_model '(.+?)' is not a known chat model","errorType":"exception","errorClass":"ConfigGenerationError","httpStatus":null,"severity":"error","filePath":"litellm/proxy/client/cli/commands/autoroute/config.py","lineNumber":119,"sourceCode":"    tiers: dict[str, tuple[str, ...]]\n    default_model: str\n    classifier: ClassifierChoice = Field(default_factory=HeuristicClassifier)\n    semantic_matching: SemanticMatchingChoice = Field(default_factory=NoSemanticMatching)\n    adaptive: bool = False\n\n\ndef validate_config(config: AutorouteConfig, discovered: tuple[DiscoveredModel, ...]) -> None:\n    \"\"\"Raise ConfigGenerationError if config references a model discovery didn't return.\"\"\"\n    chat_names: Final[frozenset[str]] = frozenset(m.name for m in chat_models(discovered))\n    embedding_names: Final[frozenset[str]] = frozenset(m.name for m in embedding_models(discovered))\n\n    for tier, models in config.tiers.items():\n        for model in models:\n            if model not in chat_names:\n                raise ConfigGenerationError(f\"Tier {tier} references unknown chat model '{model}'\")\n\n    if config.default_model not in chat_names:\n        raise ConfigGenerationError(f\"default_model '{config.default_model}' is not a known chat model\")\n\n    if isinstance(config.classifier, LLMClassifier) and config.classifier.model not in chat_names:\n        raise ConfigGenerationError(f\"classifier model '{config.classifier.model}' is not a known chat model\")\n\n    if (\n        isinstance(config.semantic_matching, SemanticMatching)\n        and config.semantic_matching.embedding_model not in embedding_names\n    ):\n        raise ConfigGenerationError(\n            f\"embedding model '{config.semantic_matching.embedding_model}' is not a known embedding model\"\n        )\n\n\ndef _litellm_proxy_deployment(name: str, base_url: str, api_key: str) -> dict[str, JsonValue]:\n    return {\n        \"model_name\": name,\n        \"litellm_params\": {\n            \"model\": f\"litellm_proxy/{name}\",","sourceCodeStart":101,"sourceCodeEnd":137,"githubUrl":"https://github.com/BerriAI/litellm/blob/77b7c6c40c0c5aa5fbcb1d6a1825ac39ca8829b8/litellm/proxy/client/cli/commands/autoroute/config.py#L101-L137","documentation":"Raised by validate_config when the config's top-level default_model is not among the chat model names found by discovery. The default model is the fallback for unroutable requests, so it must exist; a miss means a typo or stale name relative to what the target proxy actually serves. Companion checks in the same function validate tier models and classifier models.","triggerScenarios":"Thrown at litellm/proxy/client/cli/commands/autoroute/config.py:119 when the library encounters an invalid state.","commonSituations":"The autoroute default_model is not a recognized chat model.","solutions":["Set default_model to a known chat model."],"exampleFix":"default_model: gpt-4o","handlingStrategy":"validation","validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"77b7c6c40c0c5aa5fbcb1d6a1825ac39ca8829b8","analyzedAt":"2026-08-18T11:44:31.656Z","contentChangedAt":null,"schemaVersion":2},"datasetVersion":"2026-09-14T05:17:10.506Z"}