Indicium Mail TUI is a keyboard-driven email client built in Rust. It communicates with mail servers using standard IMAP and SMTP protocols, with support for implicit TLS, STARTTLS and unencrypted connections.
The application presents a three-pane interface containing the account and folder sidebar, message list and reading pane. Messages are cached locally in SQLite, enabling fast access and full-text search. RFC 2177 IDLE support delivers new messages without periodic polling.
HTML messages are converted to readable text and displayed directly within the interface. Indicium Mail TUI can also preview images, text files, source code, Markdown, PDF documents and Word documents. It supports multiple accounts, OAuth2 authentication and conventional password-based login.
Optional AI integration can draft replies through locally installed Claude, Gemini or Codex command-line clients. An integrated Model Context Protocol server can expose mail-management tools to compatible AI agents.
This is free and open source software.
Key Features
- Keyboard-driven three-pane interface.
- Read and send email using IMAP and SMTP.
- Implicit TLS, STARTTLS and plain connection modes.
- RFC 2177 IDLE support for real-time mail delivery.
- Compose, reply, reply-all and forward messages.
- Preserves email threading through Message-ID, In-Reply-To and References headers.
- Conversation view spanning messages in different folders.
- Multiple email account support.
- Interactive account setup with presets for popular providers.
- Password and OAuth2 PKCE authentication.
- OAuth2 support for Gmail, Microsoft 365, Yahoo Mail and custom providers.
- SQLite local message cache using WAL mode.
- Full-text message search using SQLite FTS5.
- Move, delete, flag and mark messages as read or unread.
- Inline rendering of HTML messages without opening a web browser.
- Attachment viewer for images, documents, text and source code.
- Displays images using terminal truecolour half-block graphics.
- File picker for adding attachments to outgoing messages.
- Resizable panes and a movable compose window.
- Mouse support throughout the interface.
- Configurable automatic mark-as-read delay.
- Optional message preview snippets.
- Customisable themes.
- Optional AI-assisted reply drafting.
- Model Context Protocol server for integration with compatible AI agents.
- Distributed as a single binary without runtime dependencies.
Website: github.com/a2-stuff/Indicium-Mail-TUI
Support:
Developer: a2-stuff
License: MIT License
Indicium Mail TUI is written in Rust. Learn Rust with our recommended free books and free tutorials.
Related Software
| Console Email Clients | |
|---|---|
| NeoMutt | Brings together many patches to extend Mutt |
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| Sup | Curses threads-with tags style email client |
| Mutt | Small but very powerful text based program |
| Alpine | Alternatively Licensed Program for Internet News and Email |
| meli | Configurable and extensible e-mail client with sane defaults |
| nmail | User interface similar to alpine / pine |
| alot | Lets notmuch handle your mailindex and uses a toolkit to render its display |
| Wanderlust | Mail/news management system with IMAP4rev1 support for Emacs |
| aerc | Billed as a "pretty good email client" |
| Cone | COnsole Newsreader And Emailer |
| matcha | Powerful, feature-rich email client for your terminal |
| bower | Curses frontend for the Notmuch email system |
| Vmail | Vim interface to Gmail |
| neatmail | Non-interactive email client |
Read our verdict in the software roundup.
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