open_file

THE RISK

High Risk

Why open_file needs a policy

Opening a file triggers an external application action (loading a file into CLO3D), which constitutes executing an operation in an external system. It is not a simple read of data, nor does it delete or modify data, but it does cause a side effect in the CLO3D environment (changing the currently loaded project/state).

From the tool's definition Open a file in CLO3D. Supports .zprj, .zpac, .avt, .obj, .fbx formats.

Documented attack patterns abuse exactly the kind of access open_file gives an agent:

POLICY

How to control open_file

PolicyLayer is an MCP gateway — it sits between your AI agents and CLO3D MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for open_file:

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "open_file": {
      "limits": [
        {
          "counter": "open_file_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

open_file 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.

Create a free account and register CLO3D MCP Server — nothing to install.
Add this policy — paste it, or build it visually.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

RATE-LIMIT THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More CLO3D MCP Server tools

Destructive delete_pattern Delete a pattern piece from the project. Destructive new_project Create a new empty CLO3D project, clearing the current scene. Execute simulate Run cloth simulation for a number of steps. Write add_fabric Add a new fabric to the project from a .zfab or .jfab file. Write assign_fabric_to_pattern Assign a fabric to a pattern piece. Write copy_pattern Duplicate a pattern piece at a given position. Write create_pattern Create a new pattern piece from vertex points. Write export_fbx Export the garment as an FBX file.

All 33 CLO3D MCP Server tools →

Execute tools on other servers

Android Forensics ADB MCP Server adb_shell_command EMBA-MCP run_emba_scan Frida Game Hacking MCP remove_breakpoint Procmon request_elevation

Go deeper

High-risk tools in CLO3D MCP Server → Every high-risk tool this server exposes, in one view.
All high-risk MCP tools → Every high-risk tool across the catalogue, and the policy pattern that contains them.
The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Agent sandbox → Bounding what an agent can execute and where the boundary should sit.
Least privilege for MCP → Granting agents the minimum tool surface the task needs.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about open_file

What does the open_file tool do? +

Open a file in CLO3D. Supports .zprj, .zpac, .avt, .obj, .fbx formats. It is categorised as a Execute tool in the CLO3D 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 open_file? +

Register the CLO3D MCP Server MCP server in PolicyLayer and add a rule for open_file: 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 CLO3D MCP Server. Nothing to install.

What risk level is open_file? +

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

Can I rate-limit open_file? +

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

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

open_file is provided by the CLO3D MCP Server MCP server (ubani-studio/clo3d-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every CLO3D MCP Server tool call.

Start from CLO3D MCP Server, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

CHECK YOUR STACK →