execute_lua · Electra One MCP: Risk & Policy

WHAT IT DOES

What execute_lua does on Electra One

AI agents invoke execute_lua to trigger actions in Electra One. 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 execute_lua needs a policy

A tool that executes code (Lua scripts) is categorized as Execute. Given the context of hardware device control (evidenced by sibling tools like device_state, device_status, get_sysex_command), arbitrary Lua execution could trigger unintended device behavior, modify presets, change MIDI mappings, or produce unexpected audio/hardware outputs. The empty description increases concern about unguarded execution.

From the tool's definition Tool name 'execute_lua' with empty description indicates capability to run Lua code. Lua is a scripting language commonly used to control hardware devices (in this context, Electra One MK2/Mini music hardware).

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

execute_lua Rate-limited

execute_lua 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": {
    "execute_lua": {
      "limits": [
        {
          "counter": "execute_lua_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 Electra One, so you can run agents against it safely.

FAQ

Questions about execute_lua

What does the execute_lua tool do? +

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

How do I enforce a policy on execute_lua? +

Register the Electra One MCP server in PolicyLayer and add a rule for execute_lua: 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 Electra One. Nothing to install.

What risk level is execute_lua? +

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

Can I rate-limit execute_lua? +

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

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

execute_lua is provided by the Electra One MCP server (roomi-fields/electra-one-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.