What this model error usually means
Google: Gemini 2.5 Pro Preview 05-06 returning 400 / context length exceeded means you should first confirm whether model ID google/gemini-2.5-pro-preview-05-06 is visible for this Google key, then separate permission, context, capability, rate limit, or route issues.
- Model: google/gemini-2.5-pro-preview-05-06
- Provider: Google
- Status code: 400