# How x402 Works

The protocol operates within the standard HTTP request/response cycle:

1. Client sends a request to a Cluster endpoint (e.g., <mark style="color:$warning;">`POST /v1/chat/completions`</mark>)
2. If no payment is attached, the server responds with <mark style="color:red;">`402 Payment Required`</mark> and includes payment instructions in the response header (amount, recipient wallet, network)
3. Client signs a USDC payment on Base and resubmits the request with the payment proof in the header
4. Server verifies the payment, processes the request, and returns the response

The entire flow adds approximately 1-2 seconds of latency on the initial request. For streaming inference, this is a one-time initial delay - subsequent tokens stream normally.


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