# browser_open

Open a URL in a stealth Chromium session.

Agent View of the PolicyLayer registry record for `browser_open`. HTML page: https://policylayer.com/tools/0xmihirk-hercules-mcp/browser-open

## Facts

- Tool: `browser_open`
- Server: Hercules MCP (`0xmihirk/hercules-mcp`) — https://policylayer.com/tools/0xmihirk-hercules-mcp.md
- Homepage: https://github.com/0xMihirK/hercules-mcp
- Risk category: Execute (High 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_open",
    "arguments": {}
  }
}
```

## Why browser_open is rated High

This tool executes a browser action (opening a URL) using a stealth Chromium session, which is an external operation with side effects. In the context of a penetration testing platform with offensive security tools, 'stealth' mode implies evasion of detection mechanisms. The tool can be used to interact with arbitrary URLs, potentially triggering malicious payloads, performing reconnaissance, or initiating attacks.

From the tool's own definition: "'Open a URL in a stealth Chromium session' — triggers an external browser action in a stealth mode within a penetration testing environment"

## Use case

AI agents invoke browser_open to trigger actions in Hercules MCP. 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.

## Recommended policy (PolicyLayer)

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

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "browser_open": {
      "limits": [
        {
          "counter": "browser_open_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}
```

## Other tools on Hercules MCP (44)

- `browser_act` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/browser-act.md
- `browser_cmd` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/browser-cmd.md
- `browser_eval` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/browser-eval.md
- `browser_session` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/browser-session.md
- `browser_wait` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/browser-wait.md
- `bruteforce_hydra` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/bruteforce-hydra.md
- `crack_john` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/crack-john.md
- `ctf_binwalk` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/ctf-binwalk.md
- `ctf_steghide` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/ctf-steghide.md
- `fuzz_dirs` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/fuzz-dirs.md
- `metasploit_generate_payload` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/metasploit-generate-payload.md
- `metasploit_manage` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/metasploit-manage.md
- `metasploit_run_module` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/metasploit-run-module.md
- `metasploit_start_listener` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/metasploit-start-listener.md
- `ncat` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/ncat.md
- `network_curl` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/network-curl.md
- `network_hping3` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/network-hping3.md
- `nmap_run_nse_script` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/nmap-run-nse-script.md
- `nmap_scan` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/nmap-scan.md
- `nmap_write_nse_script` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/nmap-write-nse-script.md
- `nuclei_run` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/nuclei-run.md
- `recon_amass` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/recon-amass.md
- `recon_dns` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/recon-dns.md
- `searchsploit` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/searchsploit.md
- `shell_exec` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/shell-exec.md
- `shell_exec_background` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/shell-exec-background.md
- `shell_kill_job` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/shell-kill-job.md
- `sqlmap_run` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/sqlmap-run.md
- `system_start_new_session` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/system-start-new-session.md
- `system_stop_container` — Execute — https://policylayer.com/tools/0xmihirk-hercules-mcp/system-stop-container.md
- …and 14 more: https://policylayer.com/tools/0xmihirk-hercules-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=0xmihirk-hercules-mcp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/0xmihirk-hercules-mcp