start_recording_and_highlight · Chrome Devtools MCP

WHAT IT DOES

What start_recording_and_highlight does on Chrome Devtools

AI agents invoke start_recording_and_highlight 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.

WHY IT NEEDS A POLICY

Why start_recording_and_highlight needs a policy

This tool executes browser operations that have observable effects but are not destructive or financial. Screen recording and DOM highlighting are execute-class actions—they trigger external operations (recording to disk, visual DOM changes) whose effects depend on arguments (the target uid). The agent can cause unintended screen captures or highlight wrong elements if misdirected.

From the tool's definition Tool performs 'start screen recording' and 'apply a deterministic highlight to a target uid', which are browser automation actions triggered through DevTools.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

start_recording_and_highlight Rate-limited

start_recording_and_highlight 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": {
    "start_recording_and_highlight": {
      "limits": [
        {
          "counter": "start_recording_and_highlight_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 Chrome Devtools, so you can run agents against it safely.

FAQ

Questions about start_recording_and_highlight

What does the start_recording_and_highlight tool do? +

Start screen recording and apply a deterministic highlight to a target uid on the selected 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 start_recording_and_highlight? +

Register the Chrome Devtools MCP server in PolicyLayer and add a rule for start_recording_and_highlight: 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 start_recording_and_highlight? +

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

Can I rate-limit start_recording_and_highlight? +

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

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

start_recording_and_highlight is provided by the Chrome Devtools MCP server (shivamprasad99/chrome-devtools-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.