# pop3_check

Check POP3 server connectivity. Reads server greeting and tests STARTTLS capability for port 110; uses implicit TLS for port 995. Does not authenticate.

Agent View of the PolicyLayer registry record for `pop3_check`. HTML page: https://policylayer.com/tools/aaronckj-mcp-nettools/pop3-check

## Facts

- Tool: `pop3_check`
- Server: Mcp Nettools (`aaronckj/mcp-nettools`) — https://policylayer.com/tools/aaronckj-mcp-nettools.md
- Homepage: https://github.com/aaronckj/mcp-nettools
- 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": "pop3_check",
    "arguments": {}
  }
}
```

## Why pop3_check is rated Low

This tool performs network diagnostics (consistent with server purpose) to verify POP3 server availability and TLS support. It reads responses from a remote server without modifying state, executing code, deleting data, or moving money. The lack of authentication means it cannot access mailbox contents.

From the tool's own definition: "Tool checks POP3 server connectivity by reading server greeting and testing STARTTLS capability without authentication. The description explicitly states 'reads server greeting' and 'does not authenticate', indicating it performs passive reconnaissance only."

## Use case

AI agents call pop3_check to retrieve information from Mcp Nettools 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 Mcp Nettools:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "pop3_check": {}
  }
}
```

## Other tools on Mcp Nettools (234)

- `http_delete` — Destructive — https://policylayer.com/tools/aaronckj-mcp-nettools/http-delete.md
- `check_mqtt` — Execute — https://policylayer.com/tools/aaronckj-mcp-nettools/check-mqtt.md
- `check_rdp` — Execute — https://policylayer.com/tools/aaronckj-mcp-nettools/check-rdp.md
- `http_post` — Execute — https://policylayer.com/tools/aaronckj-mcp-nettools/http-post.md
- `ping` — Execute — https://policylayer.com/tools/aaronckj-mcp-nettools/ping.md
- `port_scan` — Execute — https://policylayer.com/tools/aaronckj-mcp-nettools/port-scan.md
- `speedtest` — Execute — https://policylayer.com/tools/aaronckj-mcp-nettools/speedtest.md
- `traceroute` — Execute — https://policylayer.com/tools/aaronckj-mcp-nettools/traceroute.md
- `wake_on_lan` — Execute — https://policylayer.com/tools/aaronckj-mcp-nettools/wake-on-lan.md
- `arp_table` — Read — https://policylayer.com/tools/aaronckj-mcp-nettools/arp-table.md
- `bgp_lookup` — Read — https://policylayer.com/tools/aaronckj-mcp-nettools/bgp-lookup.md
- `cert_check` — Read — https://policylayer.com/tools/aaronckj-mcp-nettools/cert-check.md
- `cert_check_bulk` — Read — https://policylayer.com/tools/aaronckj-mcp-nettools/cert-check-bulk.md
- `check_actual_budget` — Read — https://policylayer.com/tools/aaronckj-mcp-nettools/check-actual-budget.md
- `check_adguard` — Read — https://policylayer.com/tools/aaronckj-mcp-nettools/check-adguard.md
- `check_alertmanager` — Read — https://policylayer.com/tools/aaronckj-mcp-nettools/check-alertmanager.md
- `check_anythingllm` — Read — https://policylayer.com/tools/aaronckj-mcp-nettools/check-anythingllm.md
- `check_appwrite` — Read — https://policylayer.com/tools/aaronckj-mcp-nettools/check-appwrite.md
- `check_archivebox` — Read — https://policylayer.com/tools/aaronckj-mcp-nettools/check-archivebox.md
- `check_audiobookshelf` — Read — https://policylayer.com/tools/aaronckj-mcp-nettools/check-audiobookshelf.md
- `check_authelia` — Read — https://policylayer.com/tools/aaronckj-mcp-nettools/check-authelia.md
- `check_authentik` — Read — https://policylayer.com/tools/aaronckj-mcp-nettools/check-authentik.md
- `check_baikal` — Read — https://policylayer.com/tools/aaronckj-mcp-nettools/check-baikal.md
- `check_bazarr` — Read — https://policylayer.com/tools/aaronckj-mcp-nettools/check-bazarr.md
- `check_beszel` — Read — https://policylayer.com/tools/aaronckj-mcp-nettools/check-beszel.md
- `check_bitwarden` — Read — https://policylayer.com/tools/aaronckj-mcp-nettools/check-bitwarden.md
- `check_bookstack` — Read — https://policylayer.com/tools/aaronckj-mcp-nettools/check-bookstack.md
- `check_calibre_web` — Read — https://policylayer.com/tools/aaronckj-mcp-nettools/check-calibre-web.md
- `check_cassandra` — Read — https://policylayer.com/tools/aaronckj-mcp-nettools/check-cassandra.md
- `check_changedetection` — Read — https://policylayer.com/tools/aaronckj-mcp-nettools/check-changedetection.md
- …and 204 more: https://policylayer.com/tools/aaronckj-mcp-nettools.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=aaronckj-mcp-nettools · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/aaronckj-mcp-nettools