custom_send_sample_email · Marketo MCP Server MCP

WHAT IT DOES

What custom_send_sample_email does on Marketo MCP Server

AI agents invoke custom_send_sample_email to trigger actions in Marketo MCP Server. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why custom_send_sample_email needs a policy

This tool executes an external operation (sending a sample email) by calling the Marketo REST API directly. Sending emails is an external side effect that cannot be trivially undone, and misuse could result in unintended emails being sent to leads or contacts.

From the tool's definition 'custom_send_sample_email' and description 'Calls the Marketo REST API directly' — triggers an external email-sending operation via the Marketo REST API

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

custom_send_sample_email Rate-limited

custom_send_sample_email stays usable, but rate-capped — a runaway agent can't fire it dozens of times 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_send_sample_email": {
      "limits": [
        {
          "counter": "custom_send_sample_email_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-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_send_sample_email

What does the custom_send_sample_email tool do? +

[CUSTOM] Calls the Marketo REST API directly (not Adobe's native MCP). It is categorised as a Execute tool in the Marketo MCP Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on custom_send_sample_email? +

Register the Marketo MCP Server MCP server in PolicyLayer and add a rule for custom_send_sample_email: 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_send_sample_email? +

custom_send_sample_email is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit custom_send_sample_email? +

Yes. Add a rate_limit block to the custom_send_sample_email 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_send_sample_email completely? +

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

custom_send_sample_email 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.