Security and limitations

Evidence boundaries

• A settlement proves the chain recorded a value transfer under its consensus rules.
• A resource hash proves equality with available bytes, not their quality or correctness.
• A manifest signature proves control of the corresponding private key, not external identity unless the public key is trusted separately.
• An anchor proves integrity and timing of a committed hash, not offchain truth or legal sufficiency.
• ISO 20022-style artifacts are not certification for an institution or market practice.

x402 risks

The public settlePayment contract function can be called by anyone who obtains a valid signed authorization. The recipient is cryptographically bound, but early submission can create timing or griefing risk. Keep authorizations short-lived and transmit them only to the intended service.

A timeout after signing can occur after settlement. Reconcile the EIP-3009 nonce, facilitator payment record and transaction before any retry. Never create a replacement payment automatically.

The hosted x402 path spends real USD₮0 on Flare mainnet. Verify chain ID, token address, recipient, amount, facilitator and validity window before signing.

API and deployment limits

The current OpenAPI omits security schemes and does not model every runtime error or x402 header. Use the documented authorization matrix and test generated clients.

Public receipt and artifact URLs are intentionally shareable. Do not place confidential business data in fields or files intended for public verification.

Self-hosted operators are responsible for database access, artifact retention, signing keys, anchor keys, contract ownership, rate limits, monitoring, backup restoration and incident response.

Unsupported conclusions

ProofRails does not establish legal identity, authority to transact, contractual performance, tax treatment, sanctions status, accounting classification or regulatory compliance.