pch-x402

pch-x402 (server SDK)

Server-side SDK to accept x402 signed-debit-per-call payments: verify EIP-712 DebitAuthorizations against a PCHEscrow deployment, compute settlement digests, and forward verified paid calls. A standalone, third-party-hostable mirror of what the PCH gateway does internally.

Phase E E.1 greenfield skeleton (worktree-e). DRAFT, NOT PUBLISHED. The JS core is tested; the Python port is a skeleton pending the Phase E full build. Source is fully readable in this package (Principle 13). Documentation and source links resolve to https://pathcoursehealth.com.

JS usage

const { verifyDebitAuthorization } = require('pch-x402');

const result = verifyDebitAuthorization(authorization, {
  domain: { name: 'PCHEscrow', version: '1', chainId: 8453, verifyingContract: ESCROW_ADDRESS },
  method: 'POST',
  canonicalUrl: 'https://your-gateway.example.com/v1/chat/completions',
  rawBody: rawRequestBodyBytes,
});
if (!result.ok) reject(result.error);

result.error is one of: missing_authorization, invalid_authorization, invalid_signature, signer_mismatch, authorization_expired, request_binding_mismatch.

EIP-712 schema (frozen at the contract deployment block)

DebitAuthorization(address wallet,uint256 amount,uint256 nonce,bytes32 requestHash,uint256 expiry)

requestHash = keccak256(abi.encode(keccak256(METHOD), keccak256(canonicalURL), keccak256(rawBody))) binds each signature to a single request. See contracts/specs/EIP712Spec.md.

Test

npm test   # node test/verifier.test.js

Status

Greenfield skeleton. Not on npm/PyPI. Publication is a Phase E hard stop.