Monarch Shield Agent Instructions

Run the local static analyzer when JavaScript or TypeScript creates or calls an automatic x402 v2 buyer client:

npx @monarch-shield/x402@0.2.0 doctor --ci --strict

Use the result as a code-review signal:

• fix supported calls without a policy seam before merge;
• prefer an onBeforePaymentCreation hook with a recognized syntactic abort return on the exact client used by the paid wrapper;
• require an MCP onPaymentRequired hook with a recognized syntactic abort return for automatic paid tool calls;
• report incomplete analysis and unsupported cross-file or custom wrappers;
• keep runtime authorization, limits, simulation, delivery, and settlement controls outside Monarch Shield.

Monarch Shield is import-aware, single-file static analysis for selected x402 v2 buyer patterns. It rejects obvious constant-dead branches but does not prove general reachability. A pass does not prove policy quality, runtime payment safety, production readiness, delivery, settlement, or compliance.

Version 0.2.0 performs local analysis only. It has no hosted payment-check API, usage reporting, or official marketplace integration.