# browser_sessionstorage_set

A write tool on the Playwright MCP MCP server.

Agent View of the PolicyLayer registry record for `browser_sessionstorage_set`. HTML page: https://policylayer.com/tools/alialobidm-playwright-mcp/browser-sessionstorage-set

## Facts

- Tool: `browser_sessionstorage_set`
- Server: Playwright MCP (`alialobidm/playwright-mcp`) — https://policylayer.com/tools/alialobidm-playwright-mcp.md
- Homepage: https://github.com/alialobidm/playwright-mcp
- Risk category: Write (Medium risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Rate-limited

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "browser_sessionstorage_set",
    "arguments": {}
  }
}
```

## Why browser_sessionstorage_set is rated Medium

This tool modifies browser session storage, which is a reversible write operation. It creates or updates session storage key-value pairs that applications may depend on. While this can influence web application behavior or state, it does not irreversibly destroy data (Destructive), execute arbitrary code (Execute), or move money (Financial).

From the tool's own definition: "Tool name 'browser_sessionstorage_set' indicates it sets session storage values in the browser. The 'set' suffix denotes a write/modification operation. Session storage persists data for the browser session and can affect application behavior."

## Use case

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

## Recommended policy (PolicyLayer)

Verdict: **Rate-limited**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Playwright MCP:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "browser_sessionstorage_set": {
      "limits": [
        {
          "counter": "browser_sessionstorage_set_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}
```

## Other tools on Playwright MCP (58)

- `browser_cookie_clear` — Destructive — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-cookie-clear.md
- `browser_cookie_delete` — Destructive — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-cookie-delete.md
- `browser_localstorage_clear` — Destructive — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-localstorage-clear.md
- `browser_localstorage_delete` — Destructive — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-localstorage-delete.md
- `browser_sessionstorage_clear` — Destructive — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-sessionstorage-clear.md
- `browser_sessionstorage_delete` — Destructive — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-sessionstorage-delete.md
- `browser_click` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-click.md
- `browser_close` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-close.md
- `browser_drag` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-drag.md
- `browser_evaluate` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-evaluate.md
- `browser_file_upload` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-file-upload.md
- `browser_fill_form` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-fill-form.md
- `browser_handle_dialog` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-handle-dialog.md
- `browser_hover` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-hover.md
- `browser_install` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-install.md
- `browser_mouse_click_xy` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-mouse-click-xy.md
- `browser_mouse_down` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-mouse-down.md
- `browser_mouse_drag_xy` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-mouse-drag-xy.md
- `browser_mouse_move_xy` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-mouse-move-xy.md
- `browser_mouse_up` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-mouse-up.md
- `browser_mouse_wheel` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-mouse-wheel.md
- `browser_navigate` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-navigate.md
- `browser_navigate_back` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-navigate-back.md
- `browser_press_key` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-press-key.md
- `browser_resize` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-resize.md
- `browser_route` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-route.md
- `browser_run_code` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-run-code.md
- `browser_select_option` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-select-option.md
- `browser_start_tracing` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-start-tracing.md
- `browser_start_video` — Execute — https://policylayer.com/tools/alialobidm-playwright-mcp/browser-start-video.md
- …and 28 more: https://policylayer.com/tools/alialobidm-playwright-mcp.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=alialobidm-playwright-mcp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/alialobidm-playwright-mcp
