Email Validator

Validate email addresses with syntax checks (RFC 5322), MX record verification, disposable/temporary email detection, and common typo suggestions. Use when v...

Security Scan

The skill's code and runtime instructions match its claimed purpose (syntax checks, MX/DNS checks, disposable-domain detection, typo suggestions); it requires no credentials or unusual installs and contains no obvious exfiltration or unrelated behavior.

Purpose & Capability

Name/description describe RFC-like syntax validation, MX (DNS) checks, disposable-domain detection, and typo suggestions — the included Python script implements those features. There are no unrelated required env vars, binaries, or config paths that would be disproportionate to an email validator.

Instruction Scope

SKILL.md instructs running the provided script with optional flags (file input, --no-dns, --no-disposable, --json). The script only reads user-supplied files, performs local checks, and runs DNS lookups (via dig/nslookup subprocess or socket.getaddrinfo) — all consistent with described functionality. It does not read other system files or transmit data to third-party HTTP endpoints.

Install Mechanism

No install spec (instruction-only plus bundled Python script). No archives or remote downloads. The script may call system tools (dig/nslookup) if present, but that is an expected method for MX lookups and not an install-time risk.

Credentials

No environment variables, credentials, or config paths are requested. The script does not attempt to access secrets or unrelated services; DNS queries are the only network-relevant activity and are intrinsic to MX checks.

Persistence & Privilege

Skill is not forced-always, does not request persistent system changes, and contains no code to modify agent config or other skills. It runs as a one-time script when invoked.

Assessment

This skill appears coherent and implements what it claims. Before installing, note: (1) MX checks invoke dig or nslookup if available and otherwise use local DNS resolution — DNS queries will reveal looked-up domains to your resolver; (2) the script reads any file path you pass it (so only validate files you trust); (3) its RFC 5322 check is a pragmatic/simplified regex (not a perfect formal parser) and disposable-domain and typo lists are finite, so expect occasional false positives/negatives. If you plan to run batch validation on large lists in a production environment, review and test the script for performance and rate-limiting behavior and consider running it in an environment where DNS queries are acceptable.

Multi-layer email validation: syntax, DNS, disposable detection, typo correction.

Quick Start

# Validate a single email
python3 scripts/email_validate.py [e-mail]

# Validate multiple emails
python3 scripts/email_validate.py [e-mail] [e-mail] [e-mail]

# JSON output
python3 scripts/email_validate.py [e-mail] --json

# Batch validate from file
python3 scripts/email_validate.py --file emails.txt

# Skip DNS checks (syntax + disposable only)
python3 scripts/email_validate.py [e-mail] --no-dns

Validation Checks

1. Syntax — RFC 5322 compliance (local part, domain, length limits)
2. MX Records — DNS lookup to verify the domain accepts email
3. Disposable Detection — Flags 80+ known throwaway email providers
4. Typo Suggestion — Catches common misspellings (gmial.com → gmail.com)

Flags

• --json — Machine-readable JSON output
• --file, -f <path> — Read emails from file (one per line)
• --no-dns — Skip MX record checks
• --no-disposable — Skip disposable email check

Exit Codes

• 0 — All emails valid
• 1 — One or more emails invalid