update_client_person · Campaign Monitor MCP: Risk & Policy

WHAT IT DOES

What update_client_person does on Campaign Monitor MCP

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

WHY IT NEEDS A POLICY

Why update_client_person needs a policy

This tool creates or modifies data reversibly—it updates person records (likely client contacts or team members) without deleting them. The change is reversible and does not execute arbitrary code or trigger external operations. Given the account management context, unauthorized updates could affect team permissions or contact details, warranting medium severity.

From the tool's definition Tool name 'update_client_person' and description 'Update a person' indicate modification of existing data. The server manages 'client/account settings' and subscriber/contact information through the Campaign Monitor API.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

update_client_person Rate-limited

update_client_person 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_client_person": {
      "limits": [
        {
          "counter": "update_client_person_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 Campaign Monitor MCP, so you can run agents against it safely.

FAQ

Questions about update_client_person

What does the update_client_person tool do? +

Update a person. It is categorised as a Write tool in the Campaign Monitor MCP 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_client_person? +

Register the Campaign Monitor MCP server in PolicyLayer and add a rule for update_client_person: 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 Campaign Monitor MCP. Nothing to install.

What risk level is update_client_person? +

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

Can I rate-limit update_client_person? +

Yes. Add a rate_limit block to the update_client_person 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_client_person completely? +

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

update_client_person is provided by the Campaign Monitor MCP server (pauliowest/cmon-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.