Please support openai compatiblity natively for adk python #7721

🔴 Required Information

Please support the OpenAI API's natively in the adk-python code without needing litellm. The OpenAI format (for better or worse) is supported by the majority of the open source models, and that would make ADK python much easier to use with them. The docs at https://adk.dev/agents/models/openai/ indicate it's not possible today.

I'm aware of the LiteLLM support, however with the 2nd supply chain attack against LiteLLM in the last 6 months or so, this is one of the riskiest dependencies in our list, and now banned from our repos via exclusions.

I believe I heard about months ago on one of the ADK community calls, yet only see an experimental one for golang. Please bring this to python as well.

Is your feature request related to a specific problem?

I want to be able to offer optional open source models to my customers in a secure manner and LiteLLM is a risk.

Describe the Solution You'd Like

Native support for OpenAI API in addition to Gemini.

Impact on your work

After the most recent successful supply chain attack on LiteLLM, it's not a viable option for us.

Willingness to contribute

Are you interested in implementing this feature yourself or submitting a PR?
No. The work is not hard technically, it's more about ensuring the ADK supports this one going forward. Even Gemini supports OpenAI style, so clearly the need us well understood by Google.