create-script · Mcp Dev MCP: Risk & Policy

WHAT IT DOES

What create-script does on Mcp Dev

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

WHY IT NEEDS A POLICY

Why create-script needs a policy

The tool creates a new script resource in the Umbraco CMS. While scripts could potentially be executed later, the tool itself is a creation/write operation. However, scripts that get deployed could execute server-side code, raising the severity to medium. The primary action is creating/writing a new file, not executing it.

From the tool's definition "Creates a new script"

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

create-script Rate-limited

create-script 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": {
    "create-script": {
      "limits": [
        {
          "counter": "create-script_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 Mcp Dev, so you can run agents against it safely.

FAQ

Questions about create-script

What does the create-script tool do? +

Creates a new script. It is categorised as a Write tool in the Mcp Dev MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on create-script? +

Register the Mcp Dev MCP server in PolicyLayer and add a rule for create-script: 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 Mcp Dev. Nothing to install.

What risk level is create-script? +

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

Can I rate-limit create-script? +

Yes. Add a rate_limit block to the create-script 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 create-script completely? +

Set action: deny in the PolicyLayer policy for create-script. 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 create-script? +

create-script is provided by the Mcp Dev MCP server (@umbraco-cms/mcp-dev). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.