network-check

name	network-check
description	Network connectivity testing toolkit for checking host reachability, port availability, and DNS resolution. Use when diagnosing network issues, verifying service availability, testing connectivity to servers, or troubleshooting DNS problems.
license	MIT
metadata	{"author":"dspy-skills","version":"1.0"}

Network Connectivity Check

A toolkit for diagnosing network connectivity issues and verifying host/service availability.

When to Use This Skill

Activate this skill when the user needs to:

• Check if a host is reachable (ping)
• Verify if a specific port is open on a host
• Perform DNS lookups to resolve domain names
• Diagnose network connectivity problems
• Test if a service is available

Available Scripts

Always run scripts with --help first to see all available options.

Script	Purpose
ping_host.py	Ping a host to check reachability
check_port.py	Check if a TCP port is open
dns_lookup.py	Perform DNS lookups

Decision Tree

Task → What do you need to check?
    │
    ├─ Is the host reachable at all?
    │   └─ Use: ping_host.py <hostname>
    │
    ├─ Is a specific service/port available?
    │   └─ Use: check_port.py <hostname> <port>
    │
    └─ Need to resolve a domain name?
        └─ Use: dns_lookup.py <domain>

Quick Examples

Check if a host is reachable:

python scripts/ping_host.py google.com
python scripts/ping_host.py 8.8.8.8 --count 5

Check if a port is open:

python scripts/check_port.py example.com 443
python scripts/check_port.py localhost 8080 --timeout 5

DNS lookup:

python scripts/dns_lookup.py example.com
python scripts/dns_lookup.py example.com --type MX

Common Use Cases

1. Verify web server is running: check_port.py myserver.com 80
2. Test SSH access: check_port.py server.local 22
3. Check database connectivity: check_port.py db.example.com 5432
4. Diagnose DNS issues: dns_lookup.py problematic-domain.com

Notes

• Scripts use Python standard library only (no external dependencies)
• Ping may require appropriate permissions on some systems
• Port checks use TCP connections (not UDP)
• DNS lookups support A, AAAA, MX, TXT, NS, and CNAME record types