Add automatic JSON argument conversion for MCP tools #4
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- Add _auto_convert_json_args wrapper to automatically parse JSON strings to dicts - Modify function annotations to accept Union[dict, str] for dict parameters - Update tool schemas to accept JSON strings for dict-typed parameters - Add auto_convert_json_args configuration option (default: True) - Remove enable_debug_logging trait in favor of standard logging levels - Improve error handling with better exception chaining
- Remove configurable auto_convert_json_args trait from MCPServer - JSON argument conversion is now always applied to all registered tools - This ensures consistent behavior and compatibility with all MCP clients - Update docstrings to reflect that conversion is always enabled - Fix ruff linting issues (imports, type annotations, unnecessary else)
- Add TestJSONArgumentConversion class with 9 comprehensive tests - Test basic dict conversion, Optional/Union types, typed dicts - Test error handling for invalid JSON strings - Test async and sync function wrappers - Test complex nested JSON structures - Test annotation modification behavior - Test that non-dict parameters remain unchanged - Add TestJSONSchemaModification class with schema tests - Test tool registration with schema modification - Test multiple dict parameters in single function - Fix union type handling for Python 3.10+ syntax (dict | None) - Support both typing.Union and new UnionType for compatibility - Update schema modification to handle both union syntaxes All 44 tests passing, including 11 new JSON conversion tests
- Rename functions for better clarity: * _auto_convert_json_args → _wrap_with_json_conversion * _modify_schema_for_json_string_support → _update_schema_for_json_args - Create shared helper _is_dict_compatible_annotation() to consolidate duplicate union type detection logic across functions - Simplify union type handling with unified approach for both typing.Union and Python 3.10+ UnionType syntax - Rename internal helper _modify_annotation_for_string_support to _add_string_to_annotation for clarity - Reduce code duplication by ~15 lines while maintaining all functionality - All 44 tests still pass, including 11 JSON conversion tests
- Format code according to project style guidelines - All tests continue to pass after formatting
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This PR adds automatic conversion of JSON string arguments to dictionary objects for MCP tools that expect dict parameters.
Summary
Testing