custom_invite_user · Marketo MCP Server MCP: Risk & Policy

WHAT IT DOES

What custom_invite_user does on Marketo MCP Server

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

WHY IT NEEDS A POLICY

Why custom_invite_user needs a policy

The tool name suggests it creates or initiates a user invitation, which is a Write operation (reversible). The empty description lowers confidence slightly, but the action aligns with user management in a Marketo context. Severity is medium because unauthorized user creation could grant access to marketing assets and customer data, but this is less severe than destructive operations or financial transactions.

From the tool's definition Tool name 'custom_invite_user' indicates creation of a user invitation or account setup action. In the context of a Marketo MCP server managing marketing assets and user access, this creates a new user record or sends an invitation (reversible write…

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

custom_invite_user Rate-limited

custom_invite_user 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": {
    "custom_invite_user": {
      "limits": [
        {
          "counter": "custom_invite_user_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

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

FAQ

Questions about custom_invite_user

What does the custom_invite_user tool do? +

custom_invite_user. It is categorised as a Write tool in the Marketo MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on custom_invite_user? +

Register the Marketo MCP Server MCP server in PolicyLayer and add a rule for custom_invite_user: 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 Marketo MCP Server. Nothing to install.

What risk level is custom_invite_user? +

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

Can I rate-limit custom_invite_user? +

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

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

custom_invite_user is provided by the Marketo MCP Server MCP server (tyron-pretorius/marketo-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.