agent-payment-x402

# Agent Payment Execution (x402) Enable AI agents to make autonomous payments with built-in spending controls. Uses the x402 HTTP payment protocol and MCP tools so agents can pay for external services, APIs, or other agents without custodial risk. ## When to Use Use when: your agent needs to pay for an API call, purchase a service, settle with another agent, enforce per-task spending limits, or manage a non-custodial wallet. Pairs naturally with cost-aware-llm-pipeline and security-review skills. ## How It Works ### x402 Protocol x402 extends HTTP 402 (Payment Required) into a machine-negotiable flow. When a server returns `402`, the agent's payment tool automatically negotiates price, checks budget, signs a transaction, and retries — no human in the loop. ### Spending Controls Every payment tool call enforces a `SpendingPolicy`: - **Per-task budget** — max spend for a single agent action - **Per-session budget** — cumulative limit across an entire session - **Allowlisted recipients** — restrict which addresses/services the agent can pay - **Rate limits** — max transactions per minute/hour ### Non-Custodial Wallets Agents hold their own keys via ERC-4337 smart accounts. The orchestrator sets policy before delegation; the agent can only spend within bounds. No pooled funds, no custodial risk. ## MCP Integration The payment layer exposes standard MCP tools that slot into any Claude Code or agent harness setup. > **Security note**: Always pin the package version. This ...