--- name: mpp-conformance description: > Validate MPP implementations against the specification — verify HTTP 402 challenge-response compliance, header formats, payment method correctness, service discovery, and production readiness. Use when auditing an MPP integration or preparing for production launch. --- # MPP Conformance & Production Readiness ## Before writing code **Fetch live docs**: 1. Fetch `https://paymentauth.org/` for the canonical specification requirements 2. Fetch `https://datatracker.ietf.org/doc/draft-ryan-httpauth-payment/` for the IETF draft compliance requirements 3. Web-search `site:docs.stripe.com payments machine mpp production` for Stripe production readiness 4. Web-search `site:paymentauth.org draft-payment-discovery` for service discovery compliance ## Protocol Compliance Checklist ### HTTP 402 Response - [ ] Returns `402 Payment Required` status code for unpaid requests - [ ] Includes `WWW-Authenticate: Payment ` header - [ ] Challenge contains required fields: `id`, `realm`, `method`, `intent`, `request` - [ ] Challenge JSON is RFC 8785 canonicalized before base64url encoding - [ ] Challenge size under 8KB - [ ] Error body follows RFC 9457 Problem Details format ### Authorization Header - [ ] Accepts `Authorization: Payment ` header - [ ] Parses credential correctly (base64url decode → JSON) - [ ] Validates payment proof against the payment method - [ ] Returns appropriate error for invalid credentials ### Payment-Receipt Header - [ ] Returns `Payment-Receipt: ` on successful payment - [ ] Receipt contains: status, method, timestamp, reference - [ ] Receipt is delivered atomically with the resource ### Challenge Binding - [ ] Uses 32-byte secret key for HMAC challenge binding - [ ] Challenge IDs are unique and non-guessable - [ ] Challenges have expiration timestamps - [ ] Expired challenges are rejected - [ ] Each challenge can only be consumed once (replay protection) ### Transport Security - [ ] TLS 1.2+ on all endpoints (TLS 1.3 recommended) - [ ] HTTPS only (port 443) - [ ] `Cache-Control: no-store` on responses with credentials - [ ] No plaintext credential logging ### Payment Methods - [ ] At least one payment method configured - [ ] Tempo: correct chain ID (4217), valid USDC contract address, valid recipient - [ ] Stripe: valid API key, correct SPT handling - [ ] Payment verification is atomic (no partial states) ### Service Discovery - [ ] `GET /openapi.json` returns valid OpenAPI 3.x document - [ ] `x-service-info` extension present with categories and docs - [ ] `x-payment-info` extension on each payable operation - [ ] All payable operations declare `402` response - [ ] OpenAPI document under 64 KB - [ ] `Cache-Control: max-age=300` on discovery endpoints - [ ] `llms.txt` available with service description ### Error Handling - [ ] `payment-required` for initial challenges - [ ] `verification-failed` for invalid proofs - [ ] `payment-expired` for expired challenges/credentials - [ ] `malformed-credential` for unparseable credentials - [ ] All errors include RFC 9457 `type` URLs ## Production Readiness Checklist ### Security - [ ] Secret key stored in environment variable or secrets manager - [ ] No hardcoded Stripe keys, wallet keys, or SPT tokens - [ ] Key rotation strategy documented - [ ] Rate limiting implemented - [ ] DDoS protection (Cloudflare, AWS Shield, etc.) ### Monitoring - [ ] Payment success/failure metrics collected - [ ] Challenge issuance rate tracked - [ ] Revenue per endpoint dashboarded - [ ] Alert on verification failure spikes - [ ] Tempo chain health monitored (if using Tempo) - [ ] Stripe API availability monitored (if using Stripe) ### Reliability - [ ] Health check endpoint (outside payment gate) - [ ] Graceful degradation if payment provider is down - [ ] Credential store (Redis/DB) for replay protection has failover - [ ] Load tested with expected traffic volume ### Operations - [ ] Deployment does not interrupt active payment sessions - [ ] Secret key rotation does not invalidate in-flight challenges - [ ] Refund process documented and tested - [ ] Billing reconciliation process defined Fetch the latest specification and IETF draft for any newly added compliance requirements before running conformance checks. --- Source attribution: OrcaQubits Original project: https://github.com/OrcaQubits/agentic-commerce-skills-plugins/blob/30cd25c74c8aa7dc49b3ec4847d463f6104439f6/dist/codex/stripe-mpp/skills/mpp-conformance/SKILL.md License: MIT License information: https://opensource.org/license/mit Original upstream instructions; downloaded from Mega AI Hub. ## Upstream license notice MIT License Copyright (c) 2024-2026 OrcaQubits AI (https://orcaqubits-ai.com) Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. # Mega AI Hub resource metadata Creator / publisher: OrcaQubits Original project: https://github.com/OrcaQubits/agentic-commerce-skills-plugins/blob/30cd25c74c8aa7dc49b3ec4847d463f6104439f6/dist/codex/stripe-mpp/skills/mpp-conformance/SKILL.md Attribution basis: Source repository record Fields of work: Marketing, Product Management, Sales Roles: Business Development, Growth Marketer, Product Marketer, Sales Engineer, Technical Product Manager Specialties: API Tools: Paymentauth, Stripe Country applicability: Country not specified Classification basis: Source catalog labels Instruction SHA-256: 471040767c994a4575059f13fecbb8a36209e5a4a6a1e79b937734376bd9ed0d