Correctness/dispute layer for x402 payloads — complements the Skyfire identity-layer pairing

[stillmarcus24]

Your x402 middleware and the docs under agents/tools/payments/x402/ make accepting payment for a Worker's output straightforward. What isn't covered anywhere in there is the next question a buyer eventually asks: the thing I just paid for — is it actually correct? We've had a live answer to that running on Base mainnet and it looks like a natural companion to what you've already shipped, especially given the edge-identity work you're doing with Skyfire.

How it works: a claim gets written into a signed, hash-chained receipt before we know how it resolves. Resolution runs against a source outside our control — a merged GitHub PR, a settled Kalshi market, a direct HTTP probe — cited by name in the receipt. Real capital backs every verdict, a $10 USDC bond with $1 slashable per proven-wrong call. A dispute is POST /dispute with the receipt hash and counter-evidence; resolution is an independent re-check against the same source, not our call to make. Bond balance and slash history are open at /notary/bond.

If Skyfire is verifying agent traffic at the edge before payment, a correctness check on the payload after payment is the logical next stop — and it'd slot cleanly next to the existing x402 examples as a "verify what you bought" pattern. Willing to write that example for examples/x402/ if it's useful, or just talk through where a dispute/correctness primitive fits your roadmap.

Real, not simulated: first settlement cleared on Base mainnet for $0.10, tx 0x8a9f.... Contract's public: 0xA3a05818d4051BFa759Fb7D936b57C072e4E0Caf.