API Proxy Keys: Track AI Costs for Any Provider Without an Admin API

What is an API proxy for cost tracking?

An API proxy sits between your application and the AI provider. Instead of calling api.openai.com directly, your app calls the proxy, which forwards the request to the provider and logs the usage data on the way through.

This approach lets you track costs for any provider — even those that don't have usage APIs. Every request is logged with token counts, model names, latency, and cost, giving you full visibility without relying on the provider's own dashboard.

Why use a proxy instead of the provider's dashboard?

Provider dashboards have limitations that a proxy solves:

• Delayed data — Many providers update usage data with a 24–48 hour delay. A proxy logs in real-time.
• No per-endpoint breakdown — Provider dashboards show total usage. A proxy can tag requests by endpoint, feature, or customer.
• Multi-provider blind spots — If you use OpenAI, Anthropic, and Gemini, you need three separate dashboards. A proxy aggregates everything.
• No API available — Some providers (Mistral, Cohere, Together AI) don't offer usage APIs at all. A proxy is the only way to track costs.

How MeterFox's proxy works

MeterFox provides a proxy gateway for every connected provider. The setup takes about 2 minutes:

• Connect your provider and enable the proxy gateway
• Copy the proxy URL and API key
• Replace the base URL in your application code (one line change)
• Usage data starts flowing immediately

The proxy forwards requests transparently — your application code works exactly the same way. The only difference is the base URL. No SDK changes, no middleware, no code refactoring.

Which providers need a proxy?

It depends on whether the provider offers a usage/admin API:

• Direct sync available — OpenAI (Admin API), Anthropic (Admin API), OpenRouter (Activity API). These providers can sync usage data automatically without a proxy.
• Proxy recommended — Google AI, Mistral, Cohere, Replicate, Together AI, Fireworks AI, DeepSeek, Groq, Perplexity. These providers don't offer usage APIs, so the proxy is the best way to track costs.

Even for providers with direct sync, the proxy adds value: real-time data instead of delayed syncs, and per-request metadata that usage APIs don't provide.

Security considerations

Routing API calls through a proxy naturally raises security questions. Here's how MeterFox handles them:

• No request payloads stored — Only metadata (model, token count, cost) is logged. Your prompts and responses are never stored.
• API keys encrypted at rest — Provider keys are encrypted using AES-256 and never exposed in logs or the UI.
• Revocable proxy keys — You can revoke proxy access instantly without affecting your provider API key.
• Transparent forwarding — The proxy doesn't modify your requests or responses in any way.

Getting started

If you're currently flying blind on costs for any provider, a proxy is the fastest path to visibility. Set it up in under 5 minutes with MeterFox, and you'll have cost data flowing before your next coffee break.