Calendar workspace
Calendar is now a first-class Herald surface with Week Time-Grid, Day Agenda, 3-Day Command, Agenda List, Calendar Search, Event Detail, RSVP actions, and source rail filtering.
Public beta · v0.5.0-beta.1
Email and calendar in your terminal, without turning setup into a project.
Herald is a keyboard-first and mouse-friendly workspace you can try
safely with a fake inbox and demo calendar before trusting it with
real accounts. Read, search, clean up, compose, plan your week, and
manage mail from the terminal, then add optional semantic search, rules, AI helpers, and trusted local agent surfaces when you want more help.
Built-in themes let Herald feel at home in your terminal.
Press ? anywhere Herald owns keyboard input to open
context-sensitive shortcut help.
brew tap herald-email/herald
brew install herald
herald --demoRecommended for macOS. Demo mode requires no email account, calendar account, API key, or Ollama install. For source installation on Linux, read the docs.
New in v0.5
Calendar, multi-account scope, and safer automation move Herald into daily-workspace territory.
The What's New in v0.5 docs page is the best product tour for v0.5.0-beta.1. Calendar is now a first-class Herald surface, Timeline absorbed cleanup browsing, and source-scoped refs make multi-account reads and mutations more explicit.
Multi-source identity
Mail and calendar data now carry source/account scope through reads, search, compose, sync, and mutations.
Timeline cleanup
Cleanup browsing moved into Timeline grouping: press `G` to cycle thread, sender, and domain modes while the old top-level Cleanup tab retires.
Account-aware mail
Multi-account mail adds source badges, Mail.app-style account sections, account-aware Compose routing, and account-scoped signatures.
calendar-aware MCP
MCP and daemon APIs gained scoped read and mutation refs, calendar read tools, and guardrails for safer multi-account automation.
Three daily surfaces
Timeline, Calendar, Automation.
Herald now has a clearer daily rhythm: scan the inbox, plan around the calendar, then let rules and trusted local agent tools handle the repeat work with account scope in view.
Timeline
Read chronologically, open split or full-screen previews, search cached mail, reply, forward, save attachments, and review cleanup groups by thread, sender, or domain.
Calendar
Plan from Week Time-Grid, Day Agenda, 3-Day Command, Agenda, Search, and Event Detail views with colored source filtering and keyboard or mouse navigation.
Automation
Use rules, cleanup managers, MCP, daemon reads, and scoped mutation guardrails when you want Herald to help without guessing which account you meant.
Calendar
A schedule view built for terminal speed.
Press 3 to open Calendar in demo mode. Try Week
Time-Grid, Day Agenda, 3-Day Command, Agenda List, Calendar Search,
Event Detail, source rail filtering, and mouse interactions.
Open Calendar guide
HERALD_THEME=sonokai-signal herald --demoWhy Herald
Try first, configure later.
Try it before you connect mail
Open demo mode with synthetic mail and calendar data, learn the workflow, then connect your real account when you are ready.
Work from one terminal workspace
Move between Timeline, Contacts, and Calendar with number keys. Read, reply, plan, search, and clean up without changing tools.
Search before you add AI
Sender, subject, body, and calendar search work from the local cache. If you add embeddings later, prefix a query with ? to search by meaning.
Automate with guardrails
Rules, cleanup grouping, MCP, and daemon APIs carry source scope so multi-account reads and mutations can target the right account.
Trust model
Runs locally. No mystery cloud layer.
Herald runs on your machine and connects to mail through accounts you configure. It keeps a local SQLite cache for fast search and navigation. AI is optional: normal email, cleanup, compose, and keyword search work without Ollama or cloud model keys.
- Local SQLite cache
- IMAP/SMTP and calendar sources configured by you
- Demo mode uses synthetic mail and calendar data
- Keyword/body/calendar search works without AI
- Semantic search requires embeddings
- Cloud AI providers are opt-in
- Bulk actions require confirmation
- MCP clients can receive mail and calendar data, so configure only clients you trust
Try without email
Start with a fake inbox, then connect your real account when you are ready.
Demo mode uses synthetic messages so you can try the terminal workflow, reading, search, compose, Calendar, cleanup grouping, and rules without sharing credentials or changing your mail.
herald --demoBuilt-in themes
A terminal mailbox can be beautiful.
Herald can inherit your terminal colors, launch with a one-off
-theme flag, or save a built-in app theme from Settings.
The built-in catalog includes warm, green, blue, violet, paper, and
terminal-inspired palettes, with local YAML themes when you want to
make your own.
Open all themes
herald --demo -theme jade-signalInstall Herald
Homebrew first on macOS, source when you need it.
The shortest macOS path is Homebrew. If you are on Linux, packaging your own build, or changing the source, follow the docs so provider setup and platform dependencies stay clear.
AI
Optional AI, only where it earns its place.
Herald does not need AI to be useful. The core client works without
Ollama or API keys. When you enable AI, the most useful parts are
semantic search, classification-assisted rules, and the Compose AI
styler: translate a draft, fix typos, make it compact, expand it with
more context, or try different moods before you accept anything.
Open search with /, then type ? query
inside search when embeddings are available.
- Search by meaning when embeddings are available
- Classify repeated mail into categories
- Use the Compose AI styler to translate, fix typos, compact, expand, and switch moods
- Use rules to route or clean up future mail
- Draft replies, but never send without explicit user action
Provider support
Mail providers and Calendar sources have different readiness levels.
Herald's v0.5 release improves the source model for mail and calendar, but OAuth is still under construction in test mode. The stable beta path remains app-password mail and CalDAV-style calendar setup where the provider supports it.
Mail providers
| Provider | Beta status |
|---|---|
| Personal Gmail | Beta, via Google App Password |
| Fastmail | IMAP/app password |
| iCloud | App-specific password |
| Proton Mail | Via Proton Mail Bridge |
| Custom IMAP/SMTP | Supported |
| Outlook | IMAP support varies by account policy |
| Gmail OAuth | Under construction in test mode; expected later, likely v0.6.0 |
Calendar sources
| Source | Beta status |
|---|---|
| Google Calendar OAuth | Under construction in test mode; expected later, likely v0.6.0 |
| Fastmail Calendar | CalDAV with app password |
| iCloud Calendar | CalDAV with app-specific password |
| Yahoo Calendar | CalDAV with app-generated password |
| Custom CalDAV | Provider-specific URL and credentials |
For v0.5, personal Gmail still uses a Google App Password. Do not paste your main Google password. Gmail OAuth and Google Calendar OAuth are test-mode work in progress, and the public OAuth path is expected in a later beta, likely v0.6.0. See the provider setup docs for current mail and calendar paths.
MCP
For agents and automation, if you want them.
Herald includes an MCP server for trusted local clients through
herald mcp. Use it to search, summarize, classify,
draft, and read calendar context from your local Herald cache. The
normal command reads your Herald config, while the demo command
serves synthetic data so you can try MCP without connecting a
mailbox or calendar account. Scoped refs and mutation guardrails
keep multi-account automation from guessing which source you meant.
Try MCP demo
claude mcp add herald-demo -- herald mcp --demoUse with real data
claude mcp add herald -- herald mcpBeta limitations
Sharp edges, named up front.
- Public beta, not finished email software.
- Source-available under FSL-1.1-ALv2.
- Clickable message links require an OSC8-compatible terminal, such as iTerm2, Kitty, WezTerm, Ghostty, Alacritty, Windows Terminal, VS Code, or many VTE-based terminals.
- Personal Gmail app-password setup is the stable Gmail path for beta.
- Gmail OAuth and Google Calendar OAuth are under construction in test mode; the public OAuth path is expected in a later beta, likely v0.6.0.
- Some AI features require Ollama or configured model providers.
- Homebrew is the default macOS install path; Linux and source setup live in the docs.