sketch_arc · Solidworks MCP: Risk & Policy

WHAT IT DOES

What sketch_arc does on Solidworks

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

WHY IT NEEDS A POLICY

Why sketch_arc needs a policy

This tool creates geometry (an arc) within an active SolidWorks sketch. It modifies the design document by adding new sketch entities, which is a reversible write operation (the arc can be deleted). No code execution, financial transactions, or irreversible destruction is involved.

From the tool's definition Draw an arc in the active sketch

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

sketch_arc Rate-limited

sketch_arc 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": {
    "sketch_arc": {
      "limits": [
        {
          "counter": "sketch_arc_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 Solidworks, so you can run agents against it safely.

FAQ

Questions about sketch_arc

What does the sketch_arc tool do? +

Draw an arc in the active sketch. It is categorised as a Write tool in the Solidworks MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on sketch_arc? +

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

What risk level is sketch_arc? +

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

Can I rate-limit sketch_arc? +

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

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

sketch_arc is provided by the Solidworks MCP server (solidworks-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.