Ram Gopal Srikar Katakam c6b87e7595 fix: preserve nested dictionaries in MCP tool parameters (#11970)
* fix: preserve nested dictionaries in MCP tool parameters (#9881)

When MCP tool schemas define object-type fields without explicit properties,
the system now treats them as free-form dictionaries (dict[str, Any]) instead
of creating empty Pydantic models. This preserves nested data structures that
were previously being lost during validation.

Before this fix:
  Input:  {'msg': {'linear': {'x': 1}}}
  Output: {'msg': {}}  # nested data lost!

After this fix:
  Input:  {'msg': {'linear': {'x': 1}}}
  Output: {'msg': {'linear': {'x': 1}}}  # preserved!

Changes:
- Modified parse_type() in json_schema.py to detect objects without properties
  and use dict[str, Any] instead of creating empty BaseModel subclasses
- Added regression test test_nested_dict_preservation_issue_9881()
- All existing tests pass (94 passed, 7 skipped)

Fixes #9881

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

* [autofix.ci] apply automated fixes

* [autofix.ci] apply automated fixes (attempt 2/3)

---------

Co-authored-by: Claude Sonnet 4.5 <noreply@anthropic.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
2026-04-06 21:22:35 +00:00
2025-03-20 00:05:55 +00:00
2026-04-01 20:35:44 +00:00
2024-06-04 09:26:13 -03:00

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