browserbase_session_close · Browserbase MCP Server MCP

WHAT IT DOES

What browserbase_session_close does on Browserbase MCP Server

AI agents use browserbase_session_close to create or update resources in Browserbase MCP Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Browserbase MCP Server environment.

WHY IT NEEDS A POLICY

Why browserbase_session_close needs a policy

This tool performs session termination and cleanup. While it stops an active resource, it is reversible (a new session can be created) and does not irreversibly delete data or cause destructive effects. It does not execute arbitrary commands, move money, or retrieve data.

From the tool's definition Closes and shuts down a browser session by terminating the Stagehand instance and session recording. This is a reversible cleanup operation that stops an active resource but does not delete persisted data or have lasting side effects beyond ending the current…

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

browserbase_session_close Rate-limited

browserbase_session_close stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "browserbase_session_close": {
      "limits": [
        {
          "counter": "browserbase_session_close_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Browserbase MCP Server, so you can run agents against it safely.

FAQ

Questions about browserbase_session_close

What does the browserbase_session_close tool do? +

Closes the current Browserbase session by properly shutting down the Stagehand instance, which handles browser cleanup and terminates the session recording. It is categorised as a Write tool in the Browserbase MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on browserbase_session_close? +

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

What risk level is browserbase_session_close? +

browserbase_session_close is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit browserbase_session_close? +

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

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

browserbase_session_close is provided by the Browserbase MCP Server MCP server (vaibhavatlys/mcp-server-browserbase). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.