outlook-cli

Microsoft Outlook from your terminal—for humans and agents.

outlook-cli is an early Rust CLI for Outlook mail and calendars through the supported Microsoft Graph API. It aims to provide calm terminal workflows for people and a deterministic, introspectable command contract for automation.

Current milestone

• Work/school and personal Microsoft accounts through delegated OAuth
• Tokens protected by the operating system credential store
• Inbox listing, message reading, sending, replying, and moving
• Calendar agenda and event creation
• Text output on a terminal and JSON when piped
• Read-only profiles, bounded collections, stable errors, and CLI Spec v0.3

Build

cargo build
cargo test

Install

cargo install outlook-cli --locked
# or, without a Rust toolchain
uv tool install outlook-cli-rs

Both packages install the outlook executable.

Configure

outlook-cli includes a maintained multitenant Microsoft Entra public-client registration, so the normal setup is simply:

outlook init

The registration requests delegated Microsoft Graph permissions only: User.Read, Mail.ReadWrite, Mail.Send, and Calendars.ReadWrite. A read-only profile requests Mail.Read and Calendars.Read instead.

For a staged or headless setup:

outlook init --no-login
outlook auth login

Read-only profiles also block remote writes locally:

outlook init --read-only

Organizations with restrictive consent policies can use their own public-client registration. Enable public client flows and supply its Application (client) ID:

outlook init --client-id YOUR_APPLICATION_ID

The same override is available through OUTLOOK_CLIENT_ID. Tenant policy can still require administrator approval, and the maintained registration is not yet publisher verified while the project is in its early development phase.

For short-lived automation, OUTLOOK_ACCESS_TOKEN overrides stored credentials.

Commands

outlook inbox --limit 20
outlook mail read MESSAGE_ID
printf 'All set.' | outlook mail reply MESSAGE_ID --body -
outlook mail send --to person@example.com --subject 'Hello' --body 'Hi'
outlook mail move MESSAGE_ID --destination archive
outlook calendar agenda --start 2026-09-03T00:00:00Z --end 2026-09-10T00:00:00Z
outlook calendar create --subject 'Project sync' \
  --start 2026-09-04T09:00:00 --end 2026-09-04T09:30:00 \
  --timezone Europe/Amsterdam --attendee person@example.com
outlook doctor --offline
outlook schema --command 'mail send'

Message and event requests opt into Graph's immutable Outlook IDs. Remote writes are blocked when the active profile is read-only. Stdout contains data; diagnostics and sign-in instructions go to stderr.

Status

The command surface is under active development. A keyboard-first TUI, drafts, attachments, search, meeting responses, contacts, and delta synchronization are planned after the core Graph and authentication contracts settle.