Agents can pay per price computation with x402, no account needed
Where enabled, a call to POST /api/compute/price with no credential answers 402 with x402 payment requirements, and a signed USDC payment buys that one call.
An agent with a funded wallet can now use the pricing endpoint without signing up. Call POST /api/compute/price with no credential to receive 402 Payment Required with the x402 payment requirements: the network, the USDC price per call and the receiving address. Repeat the same call with a signed payment in the X-PAYMENT header. The price is computed first and the payment is settled only after that, so a failed call is never charged, and the result comes back with an X-PAYMENT-RESPONSE header naming the settlement transaction. Clients on x402 v2 can use the PAYMENT-REQUIRED, PAYMENT-SIGNATURE and PAYMENT-RESPONSE headers instead.
Each payment buys exactly one call and is refused if it is presented again. Paid calls run on a shared pay-per-call workspace with the built-in and publicly listed functions. An API key still works on the same endpoint, and a request that carries one is never asked to pay. Whether pay-per-call is available, and its price, is published in /.well-known/agents.json under payments.x402 and in /llms.txt.