model_scale · Open Brush MCP Server MCP: Risk & Policy

WHAT IT DOES

What model_scale does on Open Brush MCP Server

AI agents invoke model_scale to trigger actions in Open Brush MCP Server. 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 model_scale needs a policy

This tool executes a transformation command in Open Brush that changes the visual/geometric state of a 3D model. While the effect is reversible (scale can be changed again), it is an action triggered on external software whose outcome depends on the scale argument provided.

From the tool's definition Tool operates on 3D model state within Open Brush via HTTP API; 'Sets a 3D model's scale' indicates modification of rendering/transformation properties that affects the 3D scene.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

model_scale Rate-limited

model_scale 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": {
    "model_scale": {
      "limits": [
        {
          "counter": "model_scale_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 Open Brush MCP Server, so you can run agents against it safely.

FAQ

Questions about model_scale

What does the model_scale tool do? +

Sets a 3D model's scale. It is categorised as a Execute tool in the Open Brush MCP Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on model_scale? +

Register the Open Brush MCP Server MCP server in PolicyLayer and add a rule for model_scale: 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 Open Brush MCP Server. Nothing to install.

What risk level is model_scale? +

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

Can I rate-limit model_scale? +

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

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

model_scale is provided by the Open Brush MCP Server MCP server (moz411/openbrush-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.