browser_storage_state

A read tool on the Playwright MCP server.

SERVERPlaywright MCP SOURCEalialobidm/playwright-mcp

Low RISK CLASS

Category Read

Parameters 00 required

Recommended Allowedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/alialobidm-playwright-mcp/browser-storage-state.md

WHAT IT DOES

What browser_storage_state does on Playwright MCP

AI agents call browser_storage_state to retrieve information from Playwright MCP without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

RISK

Why browser_storage_state is rated Low

The tool name 'browser_storage_state' strongly implies retrieving the current browser storage state, which typically includes cookies, localStorage, sessionStorage, and authentication tokens. This is a Read operation but carries high severity because storage state often contains sensitive authentication credentials and session tokens that could be exfiltrated.

From the tool's definition Tool name 'browser_storage_state' with empty description. Name suggests reading browser storage state (localStorage, sessionStorage, cookies, etc.).

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs browser_storage_state safely

PolicyLayer is an MCP gateway: it sits between your AI agents and Playwright MCP, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For browser_storage_state, this is the rule to start with:

browser_storage_state Allowed

browser_storage_state is read-only, so it stays allowed. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "browser_storage_state": {}
  }
}

ALLOW ONLY THIS TOOL → Instant setup, no code required.

The button opens the PolicyLayer dashboard: create your workspace, connect Playwright MCP, apply this rule, and every browser_storage_state call is checked against it from then on.

FAQ

Questions about browser_storage_state

What does the browser_storage_state tool do? +

browser_storage_state is a read tool on the Playwright MCP server. It is categorised as a Read tool in the Playwright MCP MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on browser_storage_state? +

Register the Playwright MCP server in PolicyLayer and add a rule for browser_storage_state: 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 Playwright MCP. Nothing to install.

What risk level is browser_storage_state? +

browser_storage_state is a Read tool with low risk. Read-only tools are generally safe to allow by default.

Can I rate-limit browser_storage_state? +

Yes. Add a rate_limit block to the browser_storage_state 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_storage_state completely? +

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

browser_storage_state is provided by the Playwright MCP server (alialobidm/playwright-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

KEEP EXPLORING

More on Playwright, and thousands of servers like it.

This server

All 59 Playwright tools →

Across the catalogue

browser_extract_text on Percepta MCP Server → The MCP Attack Database →

Guides

Roll out MCP under one policy →Data exfiltration →MCP token cost →