browserbase_session_close · Browserbase MCP Server MCP

WHAT IT DOES

What browserbase_session_close does on Browserbase MCP Server

AI agents invoke browserbase_session_close to trigger actions in Browserbase MCP Server. 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 browserbase_session_close needs a policy

This tool terminates an active browser session and its recording. While it cleans up resources, it's an external operation that affects a running session. It's not purely destructive (no data is deleted irreversibly) but it executes an action that triggers external operations (shutdown, cleanup, termination of recording). Misuse could disrupt ongoing automation workflows.

From the tool's definition Closes the current Browserbase session by properly shutting down the Stagehand instance, which handles browser cleanup and terminates the session recording.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

browserbase_session_close Rate-limited

browserbase_session_close 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": {
    "browserbase_session_close": {
      "limits": [
        {
          "counter": "browserbase_session_close_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 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 Execute tool in the Browserbase MCP Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

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

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 (ronsdad/mcp-server-browserbase). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.