Description of the feature request:

While the Gemini API provides usage_metadata in every response, developers often lack a standardized way to:

• Convert those raw token counts into real-time USD cost estimations based on current pricing tiers.
• Monitor the "health" of their integration
• Maintain a local log of usage for internal budgeting without needing to go into the GCP Billing console.

What problem are you trying to solve with this feature?

This utility is useful for any SDE building a cost-sensitive application or a production service that needs automated health checks before processing user requests.

Any other information you'd like to share?

No response