create_checkout · Paymongo MCP: Risk & Policy

WHAT IT DOES

What create_checkout does on Paymongo

AI agents use create_checkout to create or update resources in Paymongo — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Paymongo environment.

WHY IT NEEDS A POLICY

Why create_checkout needs a policy

This tool creates (writes) a new checkout session, which is a reversible operation—the session can be cancelled or left unused. It does not charge money directly (that would require separate payment execution), does not delete data, and does not execute arbitrary code. However, severity is high because misuse could create fraudulent checkout sessions, customer confusion, or abuse of payment infrastructure.

From the tool's definition Tool name 'create_checkout' and description 'Create a hosted checkout session (returns a checkout URL)' indicate creation of a new checkout resource. Combined with server context (PayMongo payment gateway), this creates a payment session.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

create_checkout Rate-limited

create_checkout stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "create_checkout": {
      "limits": [
        {
          "counter": "create_checkout_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

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

FAQ

Questions about create_checkout

What does the create_checkout tool do? +

Create a hosted checkout session (returns a checkout URL). It is categorised as a Write tool in the Paymongo MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on create_checkout? +

Register the Paymongo MCP server in PolicyLayer and add a rule for create_checkout: 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 Paymongo. Nothing to install.

What risk level is create_checkout? +

create_checkout is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit create_checkout? +

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

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

create_checkout is provided by the Paymongo MCP server (theyahia/paymongo-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.