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Documentation Index

Fetch the complete documentation index at: https://developers.fd.xyz/llms.txt

Use this file to discover all available pages before exploring further.

Universal Commerce Protocol (UCP) is an open standard that gives AI agents a shared way to discover merchants, browse catalogs, build carts, and pay. Prism handles the payment side: it exposes a ready-to-use handler, generates x402 payment requirements for each order, and settles the signed payment on-chain.

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What Prism Does

  1. Advertise. Prism gives merchants a xyz.fd.prism_payment handler to drop into their UCP profile. Chains, tokens, and settlement settings live in the Prism Console.
  2. Prepare. At checkout, Prism returns the x402 payment requirements for the order, with the correct token amounts and contract addresses already resolved.
  3. Settle. The merchant forwards the agent’s signed credential to Prism. Prism verifies it, executes the on-chain transfer, and returns the transaction hash.

For Merchants

Add the Prism handler, prepare checkout sessions, and settle agent payments

For Agents

Discover UCP merchants, sign x402 payments, and complete checkout cleanly

End-to-End Flow

Follow one complete purchase from discovery to on-chain settlement
Last modified on March 24, 2026