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execute_3p_developer_tool

Executes a tool exposed by the page.

How to control execute_3p_developer_tool ↓

What execute_3p_developer_tool does on Chrome DevTools

AI agents invoke execute_3p_developer_tool to trigger actions in Chrome DevTools. 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 execute_3p_developer_tool needs a policy

This tool triggers execution of third-party developer tools exposed within a web page. The actual effect is unpredictable and depends entirely on what tool the agent selects and what arguments it passes. This carries significant risk: a malicious or confused agent could invoke tools that modify page state, extract sensitive data, trigger network requests, or perform other side effects.

From the tool's definition Tool name contains 'execute' and description states 'Executes a tool exposed by the page' — this runs external code/tools whose effects depend on arguments provided by the agent.

Documented attack patterns abuse exactly the kind of access execute_3p_developer_tool gives an agent:

How to control execute_3p_developer_tool

PolicyLayer is an MCP gateway — it sits between your AI agents and Chrome DevTools, and nothing reaches the server without passing your rules. This is the rule we recommend for execute_3p_developer_tool:

policy.json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "execute_3p_developer_tool": {
      "limits": [
        {
          "counter": "execute_3p_developer_tool_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

execute_3p_developer_tool 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 Chrome DevTools — 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.
RATE-LIMIT THIS TOOL →

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Related tools and policies

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Questions about execute_3p_developer_tool

What does the execute_3p_developer_tool tool do? +

Executes a tool exposed by the page. It is categorised as a Execute tool in the Chrome DevTools 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_3p_developer_tool? +

Register the Chrome DevTools MCP server in PolicyLayer and add a rule for execute_3p_developer_tool: 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 Chrome DevTools. Nothing to install.

What risk level is execute_3p_developer_tool? +

execute_3p_developer_tool is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit execute_3p_developer_tool? +

Yes. Add a rate_limit block to the execute_3p_developer_tool 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_3p_developer_tool completely? +

Set action: deny in the PolicyLayer policy for execute_3p_developer_tool. 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_3p_developer_tool? +

execute_3p_developer_tool is provided by the Chrome DevTools MCP server (ChromeDevTools/chrome-devtools-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Chrome DevTools tool call.

Start from Chrome DevTools, 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.

50 Chrome DevTools tools catalogued and risk-classified — across an index of 43,000+ MCP servers.

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