verify_payment · Tenzro Ledger MCP: Risk & Policy

WHAT IT DOES

What verify_payment does on Tenzro Ledger MCP

AI agents use verify_payment to commit financial operations through Tenzro Ledger MCP — usually the final step of a payment, billing, or trading workflow. A call moves real money.

WHY IT NEEDS A POLICY

Why verify_payment needs a policy

This tool settles transactions on-chain, which constitutes a financial operation with irreversible blockchain finality. Misuse could result in unintended on-chain settlement of funds, making it both Financial and effectively irreversible once committed to the chain.

From the tool's definition "Verify a payment credential against a challenge and settle on-chain"

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

verify_payment Approval-gated

Any call to verify_payment 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": {
    "verify_payment": {
      "deny_if": [
        {
          "conditions": [],
          "on_deny": "Requires human approval."
        }
      ]
    }
  }
}

GATE THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Tenzro Ledger MCP, so you can run agents against it safely.

FAQ

Questions about verify_payment

What does the verify_payment tool do? +

Verify a payment credential against a challenge and settle on-chain. It is categorised as a Financial tool in the Tenzro Ledger MCP MCP Server, which means it involves financial transactions. Block by default and require explicit approval.

How do I enforce a policy on verify_payment? +

Register the Tenzro Ledger MCP server in PolicyLayer and add a rule for verify_payment: 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 Tenzro Ledger MCP. Nothing to install.

What risk level is verify_payment? +

verify_payment 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 verify_payment? +

Yes. Add a rate_limit block to the verify_payment 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 verify_payment completely? +

Set action: deny in the PolicyLayer policy for verify_payment. 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 verify_payment? +

verify_payment is provided by the Tenzro Ledger MCP server (https://canton-mcp.tenzro.network/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.