A real implementation of HTTP 402 Payment Required + delegated mandates for autonomous AI agents. With code.
AI agents need to buy things. Not in the future — today. An agent that finds a skill it needs should be able to pay for it and install it, without a human in the loop for every transaction.
This is how we implemented autonomous agent payments at MarketNow using x402 (HTTP 402 Payment Required) and AP2 (Agent Payments Protocol) delegated mandates.
The flow
Agent → POST /api/agent-purchase {skillId, mandateId}
← 402 Payment Required (x402 challenge)
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