mailhog

Set up a MailHog SMTP testing server to capture and inspect test emails.

3|2|Updated Nov 12, 2025
One-click install
npx skills add https://github.com/Whamp/whamp-claude-tools --skill mailhog
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: mailhog
Source: https://github.com/Whamp/whamp-claude-tools/tree/main/mailhog-plugin/skills/mailhog
Command: npx skills add https://github.com/Whamp/whamp-claude-tools --skill mailhog

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes scripts (resource) and references (resource) components.

What problem does it solve?

This Skill provides a comprehensive MailHog-based workflow for developing and testing email functionality, capturing messages, and validating content in local development or CI pipelines.

Core Features & Use Cases

  • Email capture & inspection: Start MailHog and capture all outgoing emails via SMTP and UI/API.
  • Message verification: Query messages, search content, and verify subject/sender/recipients.
  • Flexible storage & integration: Supports memory, MongoDB, or Maildir storage; easily integrate with various languages.

Quick Start

Start MailHog with default settings: mailhog Then configure your app to use SMTP 1025 and UI/API 8025 and verify via UI at http://localhost:8025

Frequently Asked Questions about mailhog

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I set up email testing with SMTP in my development environment?

Email testing with SMTP is accomplished by running MailHog to capture outgoing messages. Configure your application to send to SMTP port 1025, then access the UI at http://localhost:8025 to inspect captured emails, verify subjects, senders, and recipients, and validate message content.

Can I use MailHog to test emails in CI pipelines?

Yes, MailHog works in CI environments for automated email testing. Start the server in your pipeline, route SMTP traffic to port 1025, and query the API at port 8025 to verify messages programmatically without manual UI inspection.

What storage options does MailHog support for captured emails?

MailHog supports three storage backends for captured emails: memory for temporary testing, MongoDB for persistent storage across sessions, and Maildir for file-based storage. Choose based on your retention and integration requirements.

How do I verify email content and search messages in MailHog?

Message verification in MailHog is performed via the web UI or REST API at port 8025. Query stored emails to search content, filter by subject or sender, and validate recipients and message body to confirm test email behavior.

Does MailHog support authentication and outgoing SMTP configuration?

Yes, MailHog provides configurable authentication and outgoing SMTP settings. You can enable authentication for SMTP connections and configure outgoing SMTP parameters alongside optional Jim network simulation for advanced testing scenarios.