Deprecate GeminiModel in favor of GoogleModel

[DouweM]

This PR deprecates GeminiModel in favor of GoogleModel through comprehensive documentation.

Changes

• Add deprecation documentation to GeminiModel and GeminiModelSettings classes
• Maintain full backward compatibility
• Provide clear migration guidance to GoogleModel

Approach

Uses documentation-based deprecation with .. deprecated:: directives rather than runtime warnings to avoid test complexity while clearly communicating the deprecation.

Closes #2351

Generated with Claude Code

[github-actions]

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commit:	809e244
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[DouweM]

@claude

• Generate an actual deprecation warning if the model is used
• Update the GeminiModel docs to make the deprecation more explicit
• Update all other docs to use GoogleModel

[claude]

Claude finished @DouweM's task —— View job

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✅ Completed GeminiModel deprecation enhancements

Tasks Completed:

• Read current gemini.py implementation to understand existing deprecation
• Add runtime deprecation warnings to GeminiModel usage
• Update GeminiModel docs to make deprecation more explicit
• Search for all documentation that references GeminiModel
• Update all docs to use GoogleModel instead of GeminiModel
• Run linting and type checking
• Commit and push changes

Summary of Changes:

🔧 Runtime Deprecation Warnings

• Added DeprecationWarning to GeminiModel.__init__() when instantiated
• Added module-level __getattr__ to warn when GeminiModelSettings is accessed
• Warnings provide clear migration guidance to use GoogleModel instead

📚 Documentation Updates

• Added prominent deprecation warning to docs/models/gemini.md
• Updated all examples to use GoogleModel and GoogleModelSettings
• Replaced GeminiModel references with GoogleModel across documentation:
  • docs/models/index.md
  • docs/input.md
  • docs/agents.md

💻 Code Quality

• Enhanced class docstrings with DEPRECATED markers
• Fixed type checking issues with TypedDict deprecation pattern
• All linting and type checking passes ✅

The deprecation is now comprehensive with both runtime warnings for users and clear documentation guidance encouraging migration to the newer GoogleModel.

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[hyperlint-ai]

PR Change Summary

Deprecated GeminiModel in favor of GoogleModel with comprehensive documentation updates.

• Added deprecation documentation for GeminiModel and GeminiModelSettings classes.
• Ensured full backward compatibility during the transition.
• Provided clear migration guidance to GoogleModel.

Modified Files

• docs/agents.md
• docs/input.md
• docs/models/gemini.md
• docs/models/index.md

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[DouweM]

@claude Fix the failing tests. You'll likely want to ignore this particular warning in all of test_gemini.py

[claude]

Claude finished @DouweM's task —— View job

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✅ Fixed Failing Tests

Successfully fixed the test failures related to GeminiModel deprecation warnings.

Tasks Completed:

• Set up development environment and check current test status
• Examine test_gemini.py to understand test structure
• Add warning filters to ignore deprecation warnings in test_gemini.py
• Run tests to verify the fix works
• Commit and push changes

Summary:

Problem: 45 out of 46 tests in test_gemini.py were failing due to DeprecationWarning messages added to GeminiModel and GeminiModelSettings constructors.

Solution: Added pytest warning filters to the test file to suppress the deprecation warnings during testing:

pytestmark = [
    pytest.mark.anyio,
    pytest.mark.filterwarnings('ignore:GeminiModel is deprecated:DeprecationWarning'),
    pytest.mark.filterwarnings('ignore:GeminiModelSettings is deprecated:DeprecationWarning'),
]

Result: All 46 tests now pass ✅. The deprecation warnings are still active for regular usage but suppressed during testing, which is the intended behavior.

Verification: Ran linting, type checking, and full test suite - all passed successfully.

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