ChangemakerStudios/Papercut-SMTP
Papercut SMTP -- The Simple Desktop Email Server observed · 2026-08-28
Health v2 · maintenance only
99/100
- Activity 99
- Release rhythm 98
- Longevity 100
How is this computed?
round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10) — computed 2026-09-03. Adoption (stars, forks) is never an input.
- gap_med: 20
- age_days: 4025
- days_rel: 18
- days_push: 10
- n_releases_24m: 8
Adoption not part of the score
3325 stars · 306 forks observed · 2026-08-28
What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-29, confidence not recorded
Papercut SMTP is a desktop application that runs a local SMTP server and displays every email your application sends, so nothing is ever delivered to real recipients. It offers a Windows desktop UI, a Dockerized web UI, and an optional MCP server for AI agents to inspect sent emails.
Use cases
- catch emails sent during local development
- test email sending without delivering to real users
- inspect email HTML bodies, headers, and attachments
- run a fake SMTP server in Docker for CI tests
- let AI agents verify emails my app sends
- view emails from localhost:25 in a desktop app
When to choose
- you need a zero-config local SMTP catcher for development or testing
- you want a desktop GUI or Docker web UI to view captured emails
- you want AI agents to assert on sent email content via MCP
When to avoid
- you need to actually deliver email to real recipients
- you need a production SMTP relay with authentication and TLS
- you need a Linux-native desktop GUI (the desktop app is Windows-only)
Facets
application · maturity active
email http-server testing mcp developer-tools email testing windows cross-platform smtp-server email-testing desktop-application wpf fake-smtp email-viewer ai-agents docker
1 source
- readme: https://github.com/ChangemakerStudios/Papercut-SMTP · fetched 2026-08-28 · d4d4ce88cb56
Member repositories
| Repository | Role | Health v2 |
|---|---|---|
| ChangemakerStudios/Papercut-SMTP | main | 99 |
For agents
markdown · JSON · MCP: product_card(name="ChangemakerStudios/Papercut-SMTP")
Data as of 2026-08-30T08:39:29.467469+00:00 · Report a problem