x402_fetch

Fetch a URL with automatic x402 payment. If the server returns 402, signs a payment and retries.

SERVERCoWork OS SOURCECoWork-OS/CoWork-OS

Critical RISK CLASS

Category Financial

Parameters 00 required

Recommended Approval-gatedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/cowork-os/x402-fetch.md

WHAT IT DOES

What x402_fetch does on CoWork OS

AI agents use x402_fetch to commit financial operations through CoWork OS, usually the final step of a payment, billing, or trading workflow. A call moves real money.

RISK

Why x402_fetch is rated Critical

This tool automatically commits financial transactions when a server returns a 402 Payment Required response. It signs and sends payments without requiring additional user confirmation per request, meaning an AI agent could trigger real financial obligations simply by fetching URLs that respond with 402.

From the tool's definition 'automatic x402 payment', 'signs a payment and retries'

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs x402_fetch safely

PolicyLayer is an MCP gateway: it sits between your AI agents and CoWork OS, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For x402_fetch, this is the rule to start with:

x402_fetch Approval-gated

Any call to x402_fetch is blocked until a human approves it. The rest of the server keeps working.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "x402_fetch": {
      "deny_if": [
        {
          "conditions": [],
          "on_deny": "Requires human approval."
        }
      ]
    }
  }
}

GATE THIS TOOL → Instant setup, no code required.

The button opens the PolicyLayer dashboard: create your workspace, connect CoWork OS, apply this rule, and every x402_fetch call is checked against it from then on.

FAQ

Questions about x402_fetch

What does the x402_fetch tool do? +

Fetch a URL with automatic x402 payment. If the server returns 402, signs a payment and retries. It is categorised as a Financial tool in the CoWork OS MCP Server, which means it involves financial transactions. Block by default and require explicit approval.

How do I enforce a policy on x402_fetch? +

Register the CoWork OS MCP server in PolicyLayer and add a rule for x402_fetch: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches CoWork OS. Nothing to install.

What risk level is x402_fetch? +

x402_fetch is a Financial tool with critical risk. Critical-risk tools should be blocked by default and only enabled with explicit human approval.

Can I rate-limit x402_fetch? +

Yes. Add a rate_limit block to the x402_fetch rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block x402_fetch completely? +

Set action: deny in the PolicyLayer policy for x402_fetch. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides x402_fetch? +

x402_fetch is provided by the CoWork OS MCP server (CoWork-OS/CoWork-OS). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

KEEP EXPLORING

More on CoWork OS, and thousands of servers like it.

This server

All 342 CoWork OS tools → Critical-risk tools on this server →

Across the catalogue

request_x402_payment on Pop Pay →x402_call on X402 Buyer → All critical-risk MCP tools → The MCP Attack Database →

Guides

Govern MCP payment tools →Human-in-the-loop →Tool call approval →