Bug: Unclear Docs for Tracing with Non-OpenAI LLMs

[UmmeHabiba1312]

docs/tracing.md doesn’t explain using an OpenAI API key with non-OpenAI LLMs (e.g., Gemini) for free tracing. This causes confusion with the “OPENAI_API_KEY is not set” warning, as traces work but users may disable tracing.

Steps to Reproduce

1. Use non-OpenAI LLM with its API key.
2. Set OPENAI_API_KEY for tracing.
3. Run agent; traces work but docs lack guidance.

Expected

Docs clarify free tracing with OpenAI API key for non-OpenAI LLMs.

Actual

No mention in docs/tracing.md, users see warning.

Suggested Fix

Add to docs/tracing.md:

## Tracing with Non-OpenAI LLMs
Use an OpenAI API key with non-OpenAI LLMs (e.g., Gemini) for free tracing on the OpenAI dashboard.

### Example
```python
from agents import set_tracing_export_api_key, Agent, Runner, AsyncOpenAI, OpenAIChatCompletionsModel
import os, asyncio
set_tracing_export_api_key(os.getenv("OPENAI_API_KEY"))
client = AsyncOpenAI(api_key="gemini-key", base_url="https://api.gemini.com/v1")
agent = Agent(model=OpenAIChatCompletionsModel(model="gemini-model", openai_client=client))
async def main():
    result = await Runner.run(agent, "Test")
    print(result.final_output)
asyncio.run(main())

Notes

• Set OPENAI_API_KEY in .env.
• View free traces at https://platform.openai.com/traces.

Environment

• SDK: [e.g., 0.3.0]
• Python: [e.g., 3.10]
• LLM: [e.g., Gemini]

Labels

• documentation
• tracing

[UmmeHabiba1312]

I can contribute a PR to add the suggested tracing guide to docs/tracing.md. This will help users enable free tracing with non-OpenAI LLMs without confusion from the warning. Please confirm if this is the right approach.