Capture Proxy
Bring AI coding tools into Proxon by changing one base URL.
The Capture Proxy is how you bring AI coding tools into Proxon. It captures the prompts, responses, and cost from tools like Claude Code, Codex CLI, and your own SDK apps, so you and your team can see how AI is being used and what it is costing. You point your tool at a personal URL, and your requests pass through to the provider unchanged.
Using a Claude Pro or Max subscription? The proxy cannot capture calls made with a Claude subscription, and pointing Claude Code at it will usually stop the tool from working. Use the Network Observer instead.
Why this happens, and why not to set an API key
Claude Code sends a tools field on every request, and Anthropic rejects it from a subscription sign-in once the request goes through a proxy. Setting ANTHROPIC_API_KEY to force it through does not help. It quietly switches Claude Code off your subscription and onto usage-based billing, so you would be charged for every request. Only set a key if that is what you want.
Step 1: Get your personal URL
In Proxon, open Preferences, then Capture Proxy, where your personal URL is shown. Use it in your AI tool in place of the provider's address. It looks like this:
https://proxy.proxon.ai/e/your-personal-idTreat it like a password. The URL is tied to you, so keep it out of shared config files, screenshots, and anything you commit to a repo. If it gets out, rotate it. Rotating issues a new URL and turns off the old one right away.
For now, usage is tracked at the organization level, because per-person names are not turned on yet. Your usage shows up for the whole organization rather than under your name. If you set this up now, your calls will start showing under your name the moment names turn on, and nothing on your machine has to change.
Step 2: Set the base URL in your tool
Change only the base URL. Everything else, including how you sign in, stays the same.
# Add to your shell profile, or run it in your Claude Code terminal
export ANTHROPIC_BASE_URL=https://proxy.proxon.ai/e/your-personal-idWhat happens to my sign-in
Set the base URL and leave everything else alone. Keep providing your key or token the way you do today, and Proxon passes it straight through to the provider. ANTHROPIC_AUTH_TOKEN is sent as the Authorization: Bearer header, and ANTHROPIC_API_KEY is sent as the x-api-key header.
Step 3: Confirm it is capturing
Make one real call with the tool you just set up, then open My Usage. Your call should show up in the Tools section within a minute.
First call came back with a 404?
If you are the first person in your organization to set this up, a new URL can take a few seconds to become active, and your tool will not retry on its own. Wait about ten seconds and make the call again before changing anything. A 404 on your very first call is usually just this. If it is still happening after a few minutes, something else is wrong.