tmux

name	tmux
description	Use tmux for background tasks, TUI testing, and debugging layouts. Philosophy: No background bash - use tmux for full observability and direct interaction.

tmux - No Background Bash Philosophy

Core Philosophy

No background bash. Use tmux. Full observability, direct interaction.

Instead of implementing complex background task management in your application:

❌ 应用内实现	✅ 用 tmux
& 后台运行，丢失输出	tmux session 保持运行，随时查看
需要实现 job control	tmux 已有完整的 session 管理
输出不可见	tmux attach 随时重连
进程难以管理	tmux ls / tmux kill-session

tmux gives you:

• Full observability - always see what's happening
• Direct interaction - attach and type commands
• Persistence - detach and reattach later
• Isolation - each task in its own session

⛔ Safety Rules — READ FIRST

Agent 误操作 tmux kill-server 曾导致用户丢失全部 tmux session。 以下规则是硬约束，违反即可能造成不可恢复的数据丢失。

绝对禁止

禁令	原因
禁止 tmux kill-server	销毁整个 tmux 服务器，所有用户 session 全部消失
禁止遍历所有 session 并批量 kill	通配符可能命中用户的 session，最后一个 session 被杀后 server 也会退出
禁止 kill 不是你创建的 session	你不知道其他 session 的用途
禁止向唯一 pane 发送 exit / C-d	pane 关闭 → window 关闭 → session 关闭，连锁退出

正确做法

# ✅ 只 kill 你自己创建的、有明确名称的 session
tmux kill-session -t "my-agent-task" 2>/dev/null

# ✅ 需要隔离时，用 -L 创建独立 tmux 服务器（不影响默认服务器）
tmux -L agent-$$ new-session -d -s "my-task" "..."
tmux -L agent-$$ kill-session -t "my-task"

# ✅ 清理前先检查 session 是否是你创建的
tmux list-sessions  # 确认目标名称再操作

如果需要"干净环境"

# ❌ 错误：kill-server 毁掉一切
tmux kill-server

# ✅ 正确：只清理你自己的 session，用明确的命名前缀
for s in $(tmux list-sessions -F '#{session_name}' 2>/dev/null | grep '^my-prefix-'); do
  tmux kill-session -t "$s" 2>/dev/null
done

# ✅ 更好：用隔离 socket，完全不影响用户
TMUX_SOCK="tmux -L agent-$$"
$TMUX_SOCK new-session -d -s "task" "..."
# 清理时 kill-session 也不会影响用户
$TMUX_SOCK kill-session -t "task"

Quick Reference

Session Management

tmux new -s <name>              # Create named session
tmux new -s build -d            # Create detached (background)
tmux attach -t <name>           # Attach to session
tmux detach (Ctrl-b d)          # Detach from session
tmux ls                         # List sessions
tmux kill-session -t <name>     # Kill specific session
# ⛔ NEVER: tmux kill-server     # 会销毁所有 session，绝对禁止

Window & Pane Operations

# Panes
Ctrl-b %                        # Split vertical (left/right)
Ctrl-b "                        # Split horizontal (top/bottom)
Ctrl-b <arrow>                  # Navigate panes
Ctrl-b x                        # Kill pane
Ctrl-b z                        # Toggle pane zoom (fullscreen)
Ctrl-b Ctrl-<arrow>             # Resize pane
Ctrl-b { / }                    # Swap panes

# Windows
Ctrl-b c                        # New window
Ctrl-b n / p                    # Next / Previous window
Ctrl-b <number>                 # Go to window number
Ctrl-b ,                        # Rename window
Ctrl-b &                        # Kill window

Sending Commands (for scripting)

tmux send-keys -t <session> "command" Enter
tmux send-keys -t <session> Escape           # Escape key
tmux send-keys -t <session> C-c              # Ctrl+C
tmux send-keys -t <session> C-o              # Ctrl+O
tmux send-keys -t <session> M-x              # Alt+X
tmux send-keys -t <session> Space            # Space
tmux send-keys -t <session> Up               # Arrow up
tmux capture-pane -t <session> -p            # Capture screen output
tmux capture-pane -t <session> -p > out.txt  # Save to file

Common Workflows

Long-Running Build / Test

# Start build in tmux (can detach and go do other things)
tmux new -s build
go build ./...  # or make, npm build, etc.

# Detach: Ctrl-b d
# Go do other work...

# Reattach later to check progress
tmux attach -t build

Debugging Layout (Go + Delve)

┌─────────────────────────────────────────────────────┐
│  Pane 0: Program                                    │
│  $ go run ./cmd/ai                                  │
└─────────────────────────────────────────────────────┘
┌─────────────────────────────────────────────────────┐
│  Pane 1: Delve Debugger                             │
│  (dlv) break main.main                              │
│  (dlv) continue                                     │
└─────────────────────────────────────────────────────┘

# Create debug session
tmux new -s debug -d
tmux split-window -v -t debug

# Top: run program
tmux send-keys -t debug:0.0 "go run ./cmd/ai" Enter

# Bottom: attach debugger
tmux send-keys -t debug:0.1 "dlv attach \$(pgrep ai)" Enter

tmux attach -t debug

TDD Layout (Code + Test Watch)

┌──────────────────────────────┬──────────────────────────────┐
│  Pane 0: Program             │  Pane 1: Test Watch          │
│  $ go run ./cmd/ai           │  $ go test -v ./...          │
├──────────────────────────────┴──────────────────────────────┤
│  Pane 2: Logs / Shell                                       │
│  $ tail -f /var/log/ai.log                                  │
└─────────────────────────────────────────────────────────────┘

# Create TDD session
tmux new -s tdd -d
tmux split-window -h -t tdd
tmux split-window -v -t tdd:0.0

# Top-left: run program
tmux send-keys -t tdd:0.0 "go run ./cmd/ai" Enter

# Top-right: watch tests
tmux send-keys -t tdd:0.1 "go test -v ./..." Enter

# Bottom: logs
tmux send-keys -t tdd:0.2 "tail -f /var/log/ai.log" Enter

tmux attach -t tdd

Multiple Worktrees in Parallel

# Each worktree gets its own window
tmux new -s worktrees -d -c $(git rev-parse --show-toplevel)
tmux rename-window -t worktrees:0 "main"

# Add windows for each worktree
for wt in $(git worktree list --porcelain | grep "^worktree" | cut -d' ' -f2); do
    name=$(basename "$wt")
    tmux new-window -t worktrees -n "$name" -c "$wt"
done

tmux attach -t worktrees

TUI Testing Pattern

Automated testing of terminal applications with controlled environment:

#!/bin/bash
# test-tui.sh - Automated TUI testing

SESSION="tui-test"
TMUX="tmux -L test"  # Use separate socket for isolation

cleanup() {
    $TMUX kill-session -t $SESSION 2>/dev/null
}
trap cleanup EXIT

# Create session with specific dimensions (deterministic testing)
$TMUX new-session -d -s $SESSION -x 120 -y 40

# Start the TUI application
$TMUX send-keys -t $SESSION "go run ./cmd/ai" Enter
sleep 2  # Wait for startup

# Capture initial state
$TMUX capture-pane -t $SESSION -p > /tmp/initial-state.txt

# Send user input
$TMUX send-keys -t $SESSION "help" Enter
sleep 1

# Capture after input
$TMUX capture-pane -t $SESSION -p > /tmp/after-help.txt

# Verify output
if grep -q "Available commands" /tmp/after-help.txt; then
    echo "✅ Test passed: Help command works"
else
    echo "❌ Test failed: Help command not working"
    cat /tmp/after-help.txt
    exit 1
fi

# Send special keys
$TMUX send-keys -t $SESSION Escape
$TMUX send-keys -t $SESSION C-c

echo "✅ All tests passed"

Special Keys Reference

Key	tmux send-keys syntax
Escape	Escape
Enter	Enter
Space	Space
Tab	Tab
Backspace	BSpace
Delete	DC
Insert	IC
Home	Home
End	End
Page Up	PPrior
Page Down	PPage
Arrow keys	Up Down Left Right
Ctrl+X	C-x (lowercase)
Alt+X	M-x (lowercase)
Shift+Tab	BTab
F1-F12	F1 F2 ... F12

Configuration

Add to ~/.tmux.conf:

# Enable mouse (scroll, click to select pane)
set -g mouse on

# Start window numbering at 1 (easier to reach)
set -g base-index 1
setw -g pane-base-index 1

# Increase scrollback buffer
set -g history-limit 50000

# Better colors
set -g default-terminal "screen-256color"

# Easier split keys (| and -)
bind | split-window -h -c "#{pane_current_path}"
bind - split-window -v -c "#{pane_current_path}"

# Quick reload config
bind r source-file ~/.tmux.conf \; display "Config reloaded!"

# Status bar with git branch
set -g status-right '#(git branch 2>/dev/null | grep -e "\*" | sed "s/* //") | %H:%M'

# Faster key repeat
set -s escape-time 0

# Don't rename windows automatically
set -g allow-rename off

Integration with ad Editor

When running ai as a plugin in ad editor:

# Dedicated session for ad + ai development
tmux new -s ad-dev -d

# Split: ad editor | ai REPL (if needed)
tmux split-window -h -t ad-dev

# Left: ad editor with ai plugin
tmux send-keys -t ad-dev:0.0 "ad ." Enter

# Right: shell for testing
tmux send-keys -t ad-dev:0.1 "# shell for go test, git, etc." Enter

tmux attach -t ad-dev

Checking Background Task Status

When you've started a long-running task in tmux, use these commands to check status:

Task	Command
List all sessions	tmux ls
Check if session exists	tmux ls | grep <name>
View current output	tmux capture-pane -t <name> -p
View last N lines	tmux capture-pane -t <name> -p -S -50
Attach to session	tmux attach -t <name>
Send interrupt (Ctrl+C)	tmux send-keys -t <name> C-c
Kill session	tmux kill-session -t <name> ⛔ 禁止 kill-server
Wait for completion	tmux_wait.sh <name> [timeout]

Example workflow:

# 1. Start long build
tmux new -s build -d "go build ./... 2>&1 | tee /tmp/build.log"

# 2. Do other work...

# 3. Check progress
tmux capture-pane -t build -p -S -20

# 4. Or attach to see full output
tmux attach -t build

# 5. Wait for completion in script
~/.ai/skills/tmux/bin/tmux_wait.sh build 600

When to Use

Scenario	tmux Pattern
Long build/test	Single session, detach
Debugging	Split pane: program + debugger
TDD workflow	Split pane: program + test watch
Multiple features	Window per worktree
TUI testing	Automated script with capture-pane

Summary

Don't implement background task management in your app. Use tmux.

• ✅ Simple - no code to write
• ✅ Observable - always see output
• ✅ Interactive - attach anytime
• ✅ Persistent - survives disconnect
• ✅ Standard - everyone knows tmux