Add fallback model handling for parity with TypeScript SDK #317
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Add support for automatic model fallback when primary model is overloaded. The Python SDK passes the fallback_model parameter to the Claude CLI, which handles the validation and fallback logic. Changes: - Add fallback_model parameter to ClaudeAgentOptions - Pass --fallback-model to CLI subprocess - Add test for fallback model command building - Add example demonstrating fallback model usage - Add implementation documentation The validation that fallback_model != model happens at the CLI layer, keeping the SDK implementation simple and focused on parameter passing.
Use model shorthands 'opus' and 'sonnet' instead of non-existent 'claude-opus-4-5' model name in the fallback model example and test.
The example cannot reliably demonstrate the actual fallback behavior since Opus overload is not guaranteed during example execution. The test coverage is sufficient to show how to use the fallback_model parameter.
szwang
changed the title
km-anthropic
approved these changes
Nov 7, 2025
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Add support for automatic model fallback when primary model is overloaded. The Python SDK passes the fallback_model parameter to the Claude CLI, which handles the validation and fallback logic.
Changes:
The validation that fallback_model != model happens at the CLI layer, keeping the SDK implementation simple and focused on parameter passing.