browser_reset · Selenium MCP: Risk & Policy

WHAT IT DOES

What browser_reset does on SeleniumMCP

AI agents invoke browser_reset to trigger actions in SeleniumMCP. 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 browser_reset needs a policy

Restarting a browser session is an operational action that terminates the current session and starts a new one. This is an Execute-level action as it triggers an external operation (browser session management). While it discards the current session state (cookies, open tabs, etc.), it is not truly irreversible data destruction in the Destructive sense — the browser itself is restarted, not data permanently deleted.

From the tool's definition Restart the Selenium browser session

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

browser_reset Rate-limited

browser_reset 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": {
    "browser_reset": {
      "limits": [
        {
          "counter": "browser_reset_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 SeleniumMCP, so you can run agents against it safely.

FAQ

Questions about browser_reset

What does the browser_reset tool do? +

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

How do I enforce a policy on browser_reset? +

Register the Selenium MCP server in PolicyLayer and add a rule for browser_reset: 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 SeleniumMCP. Nothing to install.

What risk level is browser_reset? +

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

Can I rate-limit browser_reset? +

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

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

browser_reset is provided by the Selenium MCP server (lokii0911/seleniummcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.