Verify email
Skill gooseworks-ai/goose-skills/skills/lead-generation/capabilities/verify-email
Library of Growth & GTM skills + data APIs for Claude Code, Codex, Cursor to run ads, social, content, lead gen, seo and data scraping
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What its author says it does
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Verify if an email address is valid and deliverable
SKILL.md
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Email Verification
Setup
Read your credentials from ~/.gooseworks/credentials.json:
export GOOSEWORKS_API_KEY=$(python3 -c "import json;print(json.load(open('$HOME/.gooseworks/credentials.json'))['api_key'])")
export GOOSEWORKS_API_BASE=$(python3 -c "import json;print(json.load(open('$HOME/.gooseworks/credentials.json')).get('api_base','https://api.gooseworks.ai'))")
If ~/.gooseworks/credentials.json does not exist, tell the user to run: npx gooseworks login
All endpoints use Bearer auth: -H "Authorization: Bearer $GOOSEWORKS_API_KEY"
Check if an email address is valid, exists, and can receive mail. Prevent bounces before sending.
When to Use
- User wants to verify an email before sending
- User asks "is this email address real?"
- Cleaning an email list
- Before cold outreach to avoid bounces
- Validating user-provided email addresses
How It Works
Uses Hunter or Tomba APIs to verify email deliverability through multiple checks including syntax, domain, and mailbox verification.
Usage
Verify with Hunter
curl -s -X POST $GOOSEWORKS_API_BASE/v1/proxy/orthogonal/run \
-H "Authorization: Bearer $GOOSEWORKS_API_KEY" \
-H "Content-Type: application/json" \
-d '{"api":"hunter","path":"/v2/email-verifier","query":{"email":"[email protected]"}}'
Verify with Tomba
curl -s -X POST $GOOSEWORKS_API_BASE/v1/proxy/orthogonal/run \
-H "Authorization: Bearer $GOOSEWORKS_API_KEY" \
-H "Content-Type: application/json" \
-d '{"api":"tomba","path":"/v1/email-verifier","query":{"email":"[email protected]"}}'
Parameters
- email (required) - The email address to verify
Response
Hunter Response
Returns data object:
- status (string) -
valid,invalid,accept_all, orunknown - score (integer) - Confidence score 0-100
- result (string) -
deliverable,undeliverable, orrisky(deprecated — usestatus) - regexp (boolean) - Syntax is valid
- gibberish (boolean) - Address looks random
- disposable (boolean) - Temporary email service
- webmail (boolean) - Free webmail provider (Gmail, Yahoo, etc.)
- mx_records (boolean) - Domain has MX records
- smtp_server (boolean) - SMTP server responds
- smtp_check (boolean) - Mailbox exists on server
- accept_all (boolean) - Server accepts all addresses
- block (boolean) - Email is blocked
- sources (array) - Web pages where this email was found
Tomba Response
Returns data.email object:
- status (string) -
valid,invalid, oraccept_all - result (string) -
deliverable,undeliverable, orrisky - score (integer) - Confidence score 0-100
- smtp_provider (string) - Email provider name (e.g., "Google Workspace")
- mx (object) -
recordsarray of MX hostnames - mx_check, smtp_server, smtp_check (boolean) - Verification checks
- accept_all, greylisted, block (boolean) - Server behavior flags
- gibberish, disposable, webmail, regex (boolean) - Address quality checks
- whois (object) - Domain registration:
registrar_name,referral_url,created_date
Also returns data.sources array with uri, website_url, extracted_on, last_seen_on, still_on_page.
Result Types
| Status | Meaning | Action |
|---|---|---|
| valid | Mailbox exists and accepts mail | Safe to send |
| invalid | Mailbox doesn't exist or domain has no MX | Don't send |
| accept_all | Server accepts any address — can't confirm mailbox | Send with caution |
| unknown | Couldn't verify (timeout, greylisting) | Verify manually |
Examples
User: "Check if [email protected] is a real email"
curl -s -X POST $GOOSEWORKS_API_BASE/v1/proxy/orthogonal/run \
-H "Authorization: Bearer $GOOSEWORKS_API_KEY" \
-H "Content-Type: application/json" \
-d '{"api":"hunter","path":"/v2/email-verifier","query":{"email":"[email protected]"}}'
User: "Verify [email protected] before I send my pitch"
curl -s -X POST $GOOSEWORKS_API_BASE/v1/proxy/orthogonal/run \
-H "Authorization: Bearer $GOOSEWORKS_API_KEY" \
-H "Content-Type: application/json" \
-d '{"api":"tomba","path":"/v1/email-verifier","query":{"email":"[email protected]"}}'
Error Handling
- 400 - Missing or malformed
emailparameter - 401 - Invalid API key — check
orth auth - 429 - Rate limit exceeded — wait and retry
- If both APIs return
unknown, the mail server is likely blocking verification — try later - Tomba may return
greylisted: true— means the server deferred; retry after a few minutes
Tips
- Always verify emails before bulk sending to protect sender reputation
- "Valid" doesn't guarantee delivery - content still matters
- Role-based emails (info@, sales@) may be valid but less effective for outreach
- Disposable emails (tempmail, etc.) are detected and flagged
- Some corporate domains block verification - "unknown" doesn't mean invalid