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executeJs

executeJs

How to control executeJs ↓

What executeJs does on MCP Server Generator

AI agents invoke executeJs to trigger actions in MCP Server Generator. 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.

High Risk

Why executeJs needs a policy

JavaScript execution is a quintessential Execute category action—it runs code whose side effects depend entirely on the argument (the JavaScript code itself). Without constraints documented in an empty description, an AI agent could execute arbitrary JavaScript with broad impact on system state, browser automation, or data manipulation.

From the tool's definition Tool name 'executeJs' indicates execution of JavaScript code. The empty description prevents confirmation of scope constraints, but the name unambiguously signals dynamic code execution capability.

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

How to control executeJs

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

policy.json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "executeJs": {
      "limits": [
        {
          "counter": "executejs_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

executeJs 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.

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

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Questions about executeJs

What does the executeJs tool do? +

executeJs. It is categorised as a Execute tool in the MCP Server Generator MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on executeJs? +

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

What risk level is executeJs? +

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

Can I rate-limit executeJs? +

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

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

executeJs is provided by the MCP Server Generator MCP server (serhatuzbas/mcp-server-generator). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every MCP Server Generator tool call.

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

Free to start. No card required.

79 MCP Server Generator tools catalogued and risk-classified — across an index of 43,000+ MCP servers.

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