// 将 x402 支付执行添加到 AI 代理中——通过 MCP 工具实现每任务预算、支出控制和非托管钱包。当代理需要为 API、服务或其他代理付费时使用。
[HINT] Download the complete skill directory including SKILL.md and all related files
| name | agent-payment-x402 |
| description | 将 x402 支付执行添加到 AI 代理中——通过 MCP 工具实现每任务预算、支出控制和非托管钱包。当代理需要为 API、服务或其他代理付费时使用。 |
| origin | community |
让AI代理能够自主支付并内置消费控制。使用x402 HTTP支付协议和MCP工具，使代理能够为外部服务、API或其他代理支付，无需托管风险。
适用于：代理需要支付API调用、购买服务、与其他代理结算、强制执行每项任务消费限额，或管理非托管钱包。与成本感知LLM流水线和安全审查技能自然搭配。
x402将HTTP 402（需要付款）扩展为机器可协商的流程。当服务器返回402时，代理的支付工具会自动协商价格、检查预算、签署交易并重试——无需人工干预。
每次支付工具调用都会强制执行SpendingPolicy：
代理通过ERC-4337智能账户持有自己的密钥。编排器在委托前设置策略；代理只能在限定范围内支出。无资金池，无托管风险。
支付层暴露标准MCP工具，可无缝接入任何Claude Code或代理框架设置。
安全提示：务必锁定包版本。此工具管理私钥——未锁定的
npx安装会引入供应链风险。
{
"mcpServers": {
"agentpay": {
"command": "npx",
"args": ["agentwallet-sdk@6.0.0"]
}
}
}
| 工具 | 用途 |
|---|---|
get_balance | 检查代理钱包余额 |
send_payment | 向地址或ENS发送付款 |
check_spending | 查询剩余预算 |
list_transactions | 所有付款的审计追踪 |
注意：消费策略由编排器在委托给代理之前设置——而非代理本身。这防止代理自行提高消费限额。通过编排层或任务前钩子中的
set_policy配置策略，切勿将其作为代理可调用工具。
在构建调用agentpay MCP服务器的编排器时，在分派付费工具调用前强制执行预算。
前提条件：在添加MCP配置前安装包——
npx不带-y会在非交互环境中提示确认，导致服务器挂起：npm install -g agentwallet-sdk@6.0.0
import { Client } from "@modelcontextprotocol/sdk/client/index.js";
import { StdioClientTransport } from "@modelcontextprotocol/sdk/client/stdio.js";
async function main() {
// 1. Validate credentials before constructing the transport.
// A missing key must fail immediately — never let the subprocess start without auth.
const walletKey = process.env.WALLET_PRIVATE_KEY;
if (!walletKey) {
throw new Error("WALLET_PRIVATE_KEY is not set — refusing to start payment server");
}
// Connect to the agentpay MCP server via stdio transport.
// Whitelist only the env vars the server needs — never forward all of process.env
// to a third-party subprocess that manages private keys.
const transport = new StdioClientTransport({
command: "npx",
args: ["agentwallet-sdk@6.0.0"],
env: {
PATH: process.env.PATH ?? "",
NODE_ENV: process.env.NODE_ENV ?? "production",
WALLET_PRIVATE_KEY: walletKey,
},
});
const agentpay = new Client({ name: "orchestrator", version: "1.0.0" });
await agentpay.connect(transport);
// 2. Set spending policy before delegating to the agent.
// Always verify success — a silent failure means no controls are active.
const policyResult = await agentpay.callTool({
name: "set_policy",
arguments: {
per_task_budget: 0.50,
per_session_budget: 5.00,
allowlisted_recipients: ["api.example.com"],
},
});
if (policyResult.isError) {
throw new Error(
`Failed to set spending policy — do not delegate: ${JSON.stringify(policyResult.content)}`
);
}
// 3. Use preToolCheck before any paid action
await preToolCheck(agentpay, 0.01);
}
// Pre-tool hook: fail-closed budget enforcement with four distinct error paths.
async function preToolCheck(agentpay: Client, apiCost: number): Promise<void> {
// Path 1: Reject invalid input (NaN/Infinity bypass the < comparison)
if (!Number.isFinite(apiCost) || apiCost < 0) {
throw new Error(`Invalid apiCost: ${apiCost} — action blocked`);
}
// Path 2: Transport/connectivity failure
let result;
try {
result = await agentpay.callTool({ name: "check_spending" });
} catch (err) {
throw new Error(`Payment service unreachable — action blocked: ${err}`);
}
// Path 3: Tool returned an error (e.g., auth failure, wallet not initialised)
if (result.isError) {
throw new Error(
`check_spending failed — action blocked: ${JSON.stringify(result.content)}`
);
}
// Path 4: Parse and validate the response shape
let remaining: number;
try {
const parsed = JSON.parse(
(result.content as Array<{ text: string }>)[0].text
);
if (!Number.isFinite(parsed?.remaining)) {
throw new TypeError("missing or non-finite 'remaining' field");
}
remaining = parsed.remaining;
} catch (err) {
throw new Error(
`check_spending returned unexpected format — action blocked: ${err}`
);
}
// Path 5: Budget exceeded
if (remaining < apiCost) {
throw new Error(
`Budget exceeded: need $${apiCost} but only $${remaining} remaining`
);
}
}
main().catch((err) => {
console.error(err);
process.exitCode = 1;
});
agentwallet-sdk@6.0.0）。部署到生产环境前验证包完整性。list_transactions记录支出内容和原因。agentwallet-sdk