Pass extra_body params in the request-body to vertexAI

[bhanu97]

Title

Support for passing extra_body (eg:- labels ) parameters to Vertex AI models

Relevant issues

#13692

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Type

🐛 Bug Fix

Changes

litellm/llms/vertex_ai/gemini/transformation.py: Logic to pass along extra_body params
tests/test_litellm/llms/vertex_ai/test_vertex.py: Added Test case

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Project	Deployment	Preview	Comments	Updated (UTC)
litellm	Ready	Preview	Comment	Sep 7, 2025 1:18pm

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[bhanu97]

I’ve updated the implementation to support passing labels and other explicitly allowed fields via extra_body as per the suggestions in #9175

• extra_body keys are now merged into the Vertex AI request body without overriding already set parameters
• This keeps the request transformation safe while still giving flexibility to add optional fields like labels.

Could you please take a look and approve if everything looks good? Please let me know of any suggestions/changes.

@krrishdholakia @ishaan-jaff

[ghost]

This is not needed. Provider specific params are already passed straight through. https://docs.litellm.ai/docs/completion/provider_specific_params

Can you share the issue you face today? With steps to repro

[bhanu97]

@krrishdholakia Unfortunately, that's not the case with Vertex-AI. There are only a few parameters that are being set in the requestBody (attached the code snippet), all other optional_parameters are ignored. More info - #9175

There are other parameters which Vertex-AI support Eg: labels which is a must to have cost observability. Really looking forward for this feature to pass-along labels , please have a look

[zrottier]

Any more progress on this one? Seems to be stuck in open with solution proposed?

[github-actions]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.