execute_code_async · FreeCAD MCP: Risk & Policy

WHAT IT DOES

What execute_code_async does on FreeCAD MCP

AI agents invoke execute_code_async to trigger actions in FreeCAD MCP. 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 execute_code_async needs a policy

This tool permits execution of arbitrary Python code in the FreeCAD environment. Python code in FreeCAD can perform any operation the application supports, including creating/modifying/deleting objects, running analyses, and accessing the file system.

From the tool's definition Tool is named 'execute_code_async' and the server description states the tool enables 'executing Python code'.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

execute_code_async Rate-limited

execute_code_async 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": {
    "execute_code_async": {
      "limits": [
        {
          "counter": "execute_code_async_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 FreeCAD MCP, so you can run agents against it safely.

FAQ

Questions about execute_code_async

What does the execute_code_async tool do? +

execute_code_async. It is categorised as a Execute tool in the FreeCAD MCP MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on execute_code_async? +

Register the FreeCAD MCP server in PolicyLayer and add a rule for execute_code_async: 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 execute_code_async? +

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

Can I rate-limit execute_code_async? +

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

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

execute_code_async 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.