[feature request] Gemini Auto-Instrumentor

[Jeffrey-Peng]

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I have a customer using Gemini, but not through VertexAI. They would also prefer not to use manual instrumentation if possible

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Creation of a gemini auto-instrumentor

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I've let them know they can try the @tracer.chain decorator which captures inputs and outputs but it's not an LLM span (and therefore no prompt playground easy access and no metrics like token count),

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Code example (this does not get picked up by Vertex AI auto-instrumentor):

@tracer.chain(name="gemini-override-name")
def generate_ai_response(prompt, model="gemini-2.0-flash"):
    """
    Generates AI response using Google's Gemini API.

    Args:
        prompt (str): The input prompt to send to the model
        api_key (str): Google API key for authentication
        model (str): Model name to use, defaults to gemini-2.0-flash

    Returns:
        str: The generated response text
    """
    try:
        # import google.generativeai as genai

        # Initialize the client
        client = genai.Client(api_key=GEMINI_API_KEY)

        # Generate the response
        response = client.models.generate_content(
            model=model,
            contents=prompt
        )

        return response.text

    except Exception as e:
        return f"Error generating response: {str(e)}"

[mikeldking]

FYI this is being pushed forward as the first opentelemetry version: https://github.com/open-telemetry/opentelemetry-python-contrib/pull/3256/files/94ee68b5d8e989cd137583a29f4f3b12fab857d4..fe5a19c75b79013cbcc24bf433da2033288d39a0#r1962934673