draw_hatch · CAD- MCP: Risk & Policy

WHAT IT DOES

What draw_hatch does on CAD-MCP

AI agents use draw_hatch 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_hatch needs a policy

This tool draws a hatch fill pattern in a CAD drawing. It creates new graphical content (a fill pattern) within the document, which is a Write operation. It is reversible (the hatch can be deleted or undone). The blast radius is low as misuse would only add unwanted fill patterns to a CAD drawing, which can be corrected.

From the tool's definition 绘制填充图案 — 'draw' prefix and 'hatch fill pattern' operation creates/modifies drawing content reversibly

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

draw_hatch Rate-limited

draw_hatch 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_hatch": {
      "limits": [
        {
          "counter": "draw_hatch_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_hatch

What does the draw_hatch tool do? +

绘制填充图案。参数: points, pattern_name?, scale?, layer?, color?. 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_hatch? +

Register the CAD- MCP server in PolicyLayer and add a rule for draw_hatch: 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_hatch? +

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

Can I rate-limit draw_hatch? +

Yes. Add a rate_limit block to the draw_hatch 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_hatch completely? +

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

draw_hatch 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.