biff
Team communication for engineers who never leave the terminal.
Named after the Berkeley dog whose 1980 mail notification program was part of the same BSD family as talk, wall, finger, who, and mesg. Biff resurrects the Unix communication vocabulary as MCP-native slash commands inside Claude Code.
Platforms: macOS, Linux
Quick Start
curl -fsSL https://raw.githubusercontent.com/punt-labs/biff/8064d32/install.sh | sh
Restart Claude Code twice. Type /who to see your team.
Manual install (if you already have uv)
uv tool install punt-biff
biff install
biff doctor
Verify before running
curl -fsSL https://raw.githubusercontent.com/punt-labs/biff/8064d32/install.sh -o install.sh
shasum -a 256 install.sh
cat install.sh
sh install.sh
Features
- MCP-native --- runs inside Claude Code as slash commands, no separate app
- Interactive REPL ---
biff launches a terminal client with readline, real-time notifications, and modal talk
- BSD vocabulary ---
/who, /write, /talk, /wall --- commands engineers already know
- NATS relay --- cross-machine presence and messaging over encrypted connections
- Agent-first --- agents show up in
/who alongside humans, coordinate via /plan and /write
- Status bar --- live unread count, wall broadcasts, talk messages --- wraps your existing status line
- Zero config --- installs in one command, activates per-repo with
/biff y
What It Looks Like
See who's online
> /who
▶ NAME TTY IDLE S HOST DIR PLAN
@kai tty1 0:03 + m2-mb-air /Users/kai/code/myapp refactoring auth module
@eric tty2 1:22 + m2-mb-air /Users/eric/code/myapp reviewing PR #47
@priya tty1 0:00 + priya-mbp /Users/priya/code/myapp writing integration tests
S is message status: + means accepting messages, - means do not disturb.
Send a message
> /write @kai "auth module looks good, just one nit on the error handling"
Message sent to @kai.
Check your inbox
> /read
▶ FROM DATE MESSAGE
kai Sat Feb 15 14:01 hey, ready for review?
eric Sat Feb 15 13:45 pushed the fix for the flaky test
priya Sat Feb 15 12:30 can you look at the migration script?
More examples: /finger, /plan, /last, /wall, /talk, /mesg
Check what someone is working on
> /finger @kai
▶ Login: kai Messages: on
On since Sat Feb 15 14:01 (UTC) on tty1, idle 0:03
Host: m2-mb-air Dir: /Users/kai/code/myapp
Plan:
refactoring auth module
Set your status
> /plan "debugging the websocket reconnect logic"
Plan: debugging the websocket reconnect logic
Bead IDs auto-expand:
> /plan biff-ka4
Plan: biff-ka4: post-checkout hook: update plan from branch
Session history
> /last
▶ NAME TTY HOST LOGIN LOGOUT DURATION
@kai tty3 m2-mb-air Sat Feb 22 14:01 still logged in -
@kai tty2 m2-mb-air Sat Feb 22 11:30 Sat Feb 22 13:58 2:28
@eric tty1 m2-mb-air Sat Feb 22 09:15 Sat Feb 22 12:45 3:30
Broadcast to the team
> /wall "release freeze --- do not push to main" 2h
Wall posted (2h): release freeze --- do not push to main
Every teammate's status bar shows WALL: release freeze in bold red. Expires automatically.
Talk in real time
> /talk @kai "can you review PR #42?"
Waiting for @kai to respond...
Connected to @kai. Type 'end' to return.
BSD-style two-phase handshake: the inviter waits, the target accepts. Messages are ephemeral (NATS core pub/sub, no inbox). Either side types end to hang up.
Go do-not-disturb
> /mesg n
is n
Your status bar shows (n) instead of the unread count. Messages still accumulate --- /mesg y or /read reveals them.
Commands
