# list_watchers

Lists all active global variable watchers.

Agent View of the PolicyLayer registry record for `list_watchers`. HTML page: https://policylayer.com/tools/1600822305-js-reverse-mcp/list-watchers

## Facts

- Tool: `list_watchers`
- Server: Js Reverse (`1600822305/js-reverse-mcp`) — https://policylayer.com/tools/1600822305-js-reverse-mcp.md
- Homepage: https://github.com/1600822305/js-reverse-mcp
- Risk category: Read (Low risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Allowed

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

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

## Why list_watchers is rated Low

This tool only reads and returns information about currently active watchers in the debugging session. It has no side effects, cannot modify data, and cannot execute code or trigger external operations. It is purely informational, making it a Read category tool with low severity since even if misused by an AI agent, the worst outcome is seeing what variables are being watched—harmless information disclosure.

From the tool's own definition: "Tool description states it 'Lists all active global variable watchers' — a query operation that retrieves and reports existing debugger state without modifying or executing anything."

## Use case

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

## Recommended policy (PolicyLayer)

Verdict: **Allowed**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Js Reverse:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "list_watchers": {}
  }
}
```

## Other tools on Js Reverse (92)

- `clear_browser_cache` — Destructive — https://policylayer.com/tools/1600822305-js-reverse-mcp/clear-browser-cache.md
- `clear_cookies` — Destructive — https://policylayer.com/tools/1600822305-js-reverse-mcp/clear-cookies.md
- `clear_network_conditions` — Destructive — https://policylayer.com/tools/1600822305-js-reverse-mcp/clear-network-conditions.md
- `delete_cookie` — Destructive — https://policylayer.com/tools/1600822305-js-reverse-mcp/delete-cookie.md
- `delete_token` — Destructive — https://policylayer.com/tools/1600822305-js-reverse-mcp/delete-token.md
- `remove_breakpoint` — Destructive — https://policylayer.com/tools/1600822305-js-reverse-mcp/remove-breakpoint.md
- `remove_dom_breakpoint` — Destructive — https://policylayer.com/tools/1600822305-js-reverse-mcp/remove-dom-breakpoint.md
- `remove_network_rule` — Destructive — https://policylayer.com/tools/1600822305-js-reverse-mcp/remove-network-rule.md
- `remove_xhr_breakpoint` — Destructive — https://policylayer.com/tools/1600822305-js-reverse-mcp/remove-xhr-breakpoint.md
- `add_network_rule` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/add-network-rule.md
- `api_request` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/api-request.md
- `batch_replay` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/batch-replay.md
- `break_on_attribute_modified` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/break-on-attribute-modified.md
- `break_on_node_removed` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/break-on-node-removed.md
- `break_on_subtree_modified` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/break-on-subtree-modified.md
- `break_on_xhr` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/break-on-xhr.md
- `encode_protobuf` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/encode-protobuf.md
- `evaluate_on_callframe` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/evaluate-on-callframe.md
- `evaluate_script` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/evaluate-script.md
- `hook_crypto_functions` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/hook-crypto-functions.md
- `hook_function` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/hook-function.md
- `monitor_events` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/monitor-events.md
- `monitor_eventsource` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/monitor-eventsource.md
- `monitor_form_submit` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/monitor-form-submit.md
- `monitor_input_changes` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/monitor-input-changes.md
- `navigate_page` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/navigate-page.md
- `new_page` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/new-page.md
- `pause` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/pause.md
- `replay_request` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/replay-request.md
- `resume` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/resume.md
- …and 62 more: https://policylayer.com/tools/1600822305-js-reverse-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=1600822305-js-reverse-mcp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/1600822305-js-reverse-mcp
