update_token · Marketo MCP Server MCP: Risk & Policy

WHAT IT DOES

What update_token does on Marketo MCP Server

AI agents use update_token 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 update_token needs a policy

The tool modifies existing Marketo tokens reversibly. While tokens can affect program execution and email rendering, the action itself is a standard update operation without permanent deletion. This is classified as Write rather than Execute because it modifies configuration data rather than triggering campaign execution.

From the tool's definition Tool name 'update_token' with description 'Update an existing token in Marketo' indicates modification of existing data. Tokens in Marketo are used in email templates and programs to personalize content and control program behavior.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

update_token Rate-limited

update_token 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": {
    "update_token": {
      "limits": [
        {
          "counter": "update_token_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 update_token

What does the update_token tool do? +

Update an existing token in Marketo. 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 update_token? +

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

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

Can I rate-limit update_token? +

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

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

update_token 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.