x402 Protocol Version 2 kept the scheme model but moved payment data into headers and renamed them: X-PAYMENT → PAYMENT-SIGNATURE, X-PAYMENT-RESPONSE → PAYMENT-RESPONSE, and requirements now live in a base64 PAYMENT-REQUIRED header as a client-selectable array. This linter checks a supplied header set / 402 body for exactly these deltas, plus CAIP-2 network id formatting, and declares a protocol_version so a future wire bump is a data re-pin, not a code change. Produces a §4 compliance_control OpenChainGraph artifact.
specs/x402-specification-v2.md (Protocol Version 2, 2025-12-09). Chains, assets, and schemes are plugins, so the scheme registry is not hard-coded here; verify current scheme/network support before relying on a pass. Compute-over-supplied-inputs only, nothing here initiates, routes, or settles a payment.Copy this paragraph into Claude, OpenClaw, or any MCP-aware agent to run this exact tool, with this sample, and verify the artifact.
Run the AINumbers MCP tool `lint_x402_v2_migration`. Task: Lint a supplied x402 header set / 402 response body against the Protocol Version 2 wire format: flags deprecated v1 headers (X-PAYMENT, X-PAYMENT-RESPONSE) and their v2 replacements (PAYMENT-SIGNATURE, PAYMENT-RESPONSE), flags v1 body-based PaymentRequirements delivery (v2 moves requirements into the PAYMENT-REQUIRED header as a client-selectable array), and checks the network id for CAIP-2 format.
Call it with arguments: {"policy_parameters":{}}
Verify before trusting: call `verify_execution_hash` on mcp.ainumbers.co (https://mcp.ainumbers.co/mcp) with the parameter `claimed_hash` set to the returned `execution_hash`, passing the full artifact the run returned (the object containing `policy_parameters` + `output_payload` + `execution_hash`; equivalently `policy_parameters` + `output_payload` with `claimed_hash`), not the bare hash string.
Return the ledger link https://ledger.ainumbers.co/ so a human can re-verify without contacting us.
PII rule: All inputs are processed locally in your browser. No data is transmitted. Do not enter real personal data — use synthetic or anonymised inputs only.
Open the tool with the sample prefilled: https://ainumbers.co/chaingraph/art-393-x402-v2-migration-linter.html#p=v1.H4sIAAAAAAAA_wECAP3_e31Dv6ajAgAAAA