save_scad · 3D MCP Server MCP: Risk & Policy

WHAT IT DOES

What save_scad does on 3D MCP Server

AI agents use save_scad to create or update resources in 3D MCP Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your 3D MCP Server environment.

WHY IT NEEDS A POLICY

Why save_scad needs a policy

This tool performs a write operation that creates or modifies a .scad file in the filesystem. While it is reversible (files can be deleted or overwritten), it has medium severity because an AI agent could fill disk space, overwrite important design files, or create files with malicious OpenSCAD code that could harm downstream users who open/process them.

From the tool's definition Tool description states it 'Save[s] the scene as an OpenSCAD .scad file', which creates or writes a file to storage.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

save_scad Rate-limited

save_scad 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": {
    "save_scad": {
      "limits": [
        {
          "counter": "save_scad_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 3D MCP Server, so you can run agents against it safely.

FAQ

Questions about save_scad

What does the save_scad tool do? +

Save the scene as an OpenSCAD .scad file. It is categorised as a Write tool in the 3D MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on save_scad? +

Register the 3D MCP Server MCP server in PolicyLayer and add a rule for save_scad: 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 3D MCP Server. Nothing to install.

What risk level is save_scad? +

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

Can I rate-limit save_scad? +

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

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

save_scad is provided by the 3D MCP Server MCP server (jagjerez-org/3d-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.