create_activity · CiviCRM MCP Server MCP: Risk & Policy

WHAT IT DOES

What create_activity does on CiviCRM MCP Server

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

WHY IT NEEDS A POLICY

Why create_activity needs a policy

This tool creates a new activity record in CiviCRM, which is a standard Write operation—it adds data to the system that can be modified or deleted later. While activities might trigger workflows or notifications, the core function is record creation.

From the tool's definition Tool name 'create_activity' and description 'Create a new activity in CiviCRM' indicate data creation. The sibling tools on this server include both Write operations (create_*) and Destructive operations (delete_*), confirming this server manages CiviCRM…

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

create_activity Rate-limited

create_activity 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_activity": {
      "limits": [
        {
          "counter": "create_activity_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 CiviCRM MCP Server, so you can run agents against it safely.

FAQ

Questions about create_activity

What does the create_activity tool do? +

Create a new activity in CiviCRM with custom fields. It is categorised as a Write tool in the CiviCRM 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 create_activity? +

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

What risk level is create_activity? +

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

Can I rate-limit create_activity? +

Yes. Add a rate_limit block to the create_activity 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_activity completely? +

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

create_activity is provided by the CiviCRM MCP Server MCP server (johncallhub/civicrm-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.