draw_polyline · CAD- MCP: Risk & Policy

WHAT IT DOES

What draw_polyline does on CAD-MCP

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

WHY IT NEEDS A POLICY

Why draw_polyline needs a policy

draw_polyline creates or modifies CAD drawing data by adding polyline objects, which is a reversible Write operation. It does not execute arbitrary code or shell commands (Execute), nor does it permanently delete data (Destructive). The severity is medium because misuse could create unwanted geometry in designs, but changes can be undone via standard CAD undo/redo or by editing the drawing file.

From the tool's definition Tool name 'draw_polyline' and description '绘制多段线' (draw polyline) with parameters for points, closed status, layer, color, and lineweight. This creates geometric data in CAD drawings.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

draw_polyline Rate-limited

draw_polyline 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": {
    "draw_polyline": {
      "limits": [
        {
          "counter": "draw_polyline_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 CAD-MCP, so you can run agents against it safely.

FAQ

Questions about draw_polyline

What does the draw_polyline tool do? +

绘制多段线。参数: points, closed?, layer?, color?, lineweight?. It is categorised as a Write tool in the CAD-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 draw_polyline? +

Register the CAD- MCP server in PolicyLayer and add a rule for draw_polyline: 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 CAD-MCP. Nothing to install.

What risk level is draw_polyline? +

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

Can I rate-limit draw_polyline? +

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

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

draw_polyline is provided by the CAD- MCP server (piexl/cad-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.