Fastmail

Drive the product through a documented public API G

Agent access

Connect an agent via an official MCP server G

Agent access

Delegate tasks to a built-in AI assistant inside the product G

Agentic features

Plug MCP servers into this product so it can use their tools G

Agent access

Issue scoped/least-privilege API credentials for an agent G

Agent access

Run the product headlessly / in CI for automation G

Agent access

Set up automations that run autonomously in the background G

Agentic features

Subscribe to events via webhooks G

Agent access

Download a machine-readable API spec (OpenAPI or equivalent) G

Api quality

Build against official SDKs G

Agent access

Explore an interactive API reference with runnable examples G

Api quality

Operate the product with natural-language commands G

Agentic features

Point an agent at llms.txt or agent-oriented docs G

Agent access

Rely on versioned APIs with a documented deprecation policy G

Api quality

Get AI-generated insights and suggestions from my data inside the product G

Agentic features

Use an official CLI G

Agent access

Test against a sandbox environment without touching production data G

Api quality

Connect several accounts across providers — Gmail, Microsoft 365, IMAP — and work them from one place C

Multi account

Define rules that trigger actions automatically on events G

Do everything from the keyboard — comprehensive shortcuts and a command palette — in an interface fast enough to never make me wait C

Shortcuts

Split my inbox into focused streams — important, team, newsletters, calendar invites — so triage happens in priority order, not arrival order C

Inbox structure

Export all of my data in open formats and leave G

AI triages my inbox for me — auto-labeling, categorizing, and surfacing what needs attention — with behavior I can steer and audit C

Ai triage

My team works shared inboxes together — shared accounts or team channels where everyone sees the same conversation state C

Shared inbox

AI drafts replies in my own voice and tone — ready to review and send, not generic boilerplate C

Ai drafting

Prevent my data from being used to train AI models G

Self-host the core product G

My mail stays reachable over open protocols and standard formats — IMAP/JMAP/SMTP access and standards-based export — so no client can lock me in C

Portability

Schedule an email to send later and undo a send within a grace window C

Sending

See my calendar, respond to invites, and create events without leaving the email client C

Calendar

Read, search, and write email offline, with changes syncing when I reconnect C

Offline

An external agent — Claude, ChatGPT, or my own — can read, triage, draft, and send my email end to end through a documented connection C

Agent workflows

Do everything through the API that I can do in the UI G

Perform bulk operations across many items at once G

Snooze conversations and set follow-up reminders that resurface a thread if nobody replies C

Followups

Insert saved snippets or templates — with variables and attachments — instead of retyping the same reply C

Templates

Assign conversations to teammates and route incoming mail with rules so ownership is explicit C

Routing

Search is fast and precise — operators, filters, and ranked results across my full mail history C

Search

Ask an assistant questions across my whole inbox and calendar — who said what, what's outstanding — and get grounded answers C

Ai assistant

Read the product's source under an open license G

Schedule recurring jobs or workflows G

Choose where my data is stored (region/residency) G

Control data retention and deletion G

Opt out of telemetry and usage tracking G

The client protects me from senders' tracking — blocking read pixels by default — and is transparent about what it does with my mail data C

Protection

We can discuss an email in an internal side-thread — comments and @mentions beside the message — instead of forwarding copies around C

Shared inbox

Use aliases or masked addresses so sign-ups and strangers never learn my real address C

Protection

Import my complete mail history and contacts from my old provider or client C

Migration

Select many conversations at once and archive, label, or mark them done in one stroke C

Inbox structure

Share my availability or insert bookable meeting times directly into an email C

Calendar

Version, review, and roll back my automations G

See whether and when recipients opened my email C

Sending

Self-host the email app and keep the mail pipeline under my own control C

Portability

The same inbox also handles adjacent customer channels — SMS, WhatsApp, social, or live chat — beside email C

Channels