create_object · FreeCAD MCP: Risk & Policy

WHAT IT DOES

What create_object does on FreeCAD MCP

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

WHY IT NEEDS A POLICY

Why create_object needs a policy

Creating CAD objects is a reversible write operation. It modifies the CAD document state but does not execute arbitrary code (that's handled by execute_code) or permanently destroy data. The blast radius is medium because malicious object creation could produce misleading designs or consume resources, but changes can be undone.

From the tool's definition Tool name 'create_object' indicates data creation. Server description confirms tools for 'creating, editing, and deleting objects' in FreeCAD CAD modeling context.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

create_object Rate-limited

create_object 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_object": {
      "limits": [
        {
          "counter": "create_object_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 FreeCAD MCP, so you can run agents against it safely.

FAQ

Questions about create_object

What does the create_object tool do? +

create_object. It is categorised as a Write tool in the FreeCAD 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 create_object? +

Register the FreeCAD MCP server in PolicyLayer and add a rule for create_object: 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 FreeCAD MCP. Nothing to install.

What risk level is create_object? +

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

Can I rate-limit create_object? +

Yes. Add a rate_limit block to the create_object 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_object completely? +

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

create_object is provided by the FreeCAD MCP server (yaeshio/freecad-mcp-for-ydga). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.