diff --git a/docs/plans/2025-12-29-pa-tmux-theme-design.md b/docs/plans/2025-12-29-pa-tmux-theme-design.md
new file mode 100644
index 0000000..f16282c
--- /dev/null
+++ b/docs/plans/2025-12-29-pa-tmux-theme-design.md
@@ -0,0 +1,91 @@
+# PA Tmux Session Visual Theme Design
+
+**Date:** 2025-12-29
+**Status:** Approved
+
+## Problem
+
+The PA agent tmux session runs with `--dangerously-skip-permissions`, giving it elevated privileges. There's no visual indicator distinguishing it from normal tmux sessions, making it easy to forget you're in a privileged context.
+
+## Solution
+
+Create a separate tmux config file (`~/.tmux-pa.conf`) that applies a distinct "power mode" purple theme to the PA session only, while keeping Rose Pine Moon as the default for all other sessions.
+
+## Design Decisions
+
+| Decision | Choice | Rationale |
+|----------|--------|-----------|
+| Visual approach | Status bar color change | Immediate, unmistakable feedback |
+| Color tone | Purple/magenta "power mode" | Conveys capability, not danger |
+| Theme style | Dracula-ish purple | Distinct from Rose Pine Moon |
+| Mode indicator | `⚡ PA` badge | Explicit, clean, punchy |
+| Implementation | Separate config file | Clean separation, easy to maintain |
+
+## Color Palette
+
+| Element | Color | Hex |
+|---------|-------|-----|
+| Background | Deep purple | `#282a36` |
+| Foreground | Light gray | `#f8f8f2` |
+| Accent (active) | Bright purple | `#bd93f9` |
+| Accent (secondary) | Cyan | `#8be9fd` |
+| Accent (highlight) | Pink | `#ff79c6` |
+| Muted text | Comment gray | `#6272a4` |
+
+## Files to Create/Modify
+
+### New: `~/.tmux-pa.conf`
+
+```bash
+# Source base config (inherits keybindings, plugins, settings)
+source-file ~/.tmux.conf
+
+# === Dracula Purple "Power Mode" Theme ===
+
+# Status bar base
+set -g status-style "bg=#282a36,fg=#f8f8f2"
+
+# Left: PA badge
+set -g status-left "#[bg=#ff79c6,fg=#282a36,bold] ⚡ PA #[bg=#282a36,fg=#ff79c6] "
+set -g status-left-length 20
+
+# Window status
+set -g window-status-format "#[fg=#6272a4] #I:#W "
+set -g window-status-current-format "#[fg=#bd93f9,bold] #I:#W "
+
+# Right: host, directory, time
+set -g status-right "#[fg=#8be9fd]#h #[fg=#6272a4]| #[fg=#bd93f9]#{pane_current_path} #[fg=#6272a4]| #[fg=#ff79c6]%Y-%m-%d %H:%M "
+set -g status-right-length 80
+
+# Pane borders
+set -g pane-border-style "fg=#6272a4"
+set -g pane-active-border-style "fg=#bd93f9"
+
+# Message styling
+set -g message-style "bg=#282a36,fg=#ff79c6"
+```
+
+### Modify: `~/.claude/automation/pa-mode`
+
+Change the tmux invocation to use the PA-specific config:
+
+```bash
+# Before
+exec tmux new-session -A -s "$SESSION_NAME" ...
+
+# After
+exec tmux -f ~/.tmux-pa.conf new-session -A -s "$SESSION_NAME" ...
+```
+
+## What Stays Unchanged
+
+- `~/.tmux.conf` - Rose Pine Moon default, untouched
+- All other tmux sessions - Continue using default config
+- All keybindings, plugins, history settings - Inherited via `source-file`
+
+## Testing
+
+1. Start a normal tmux session - should show Rose Pine Moon theme
+2. Run `pa-mode` - should show Dracula purple theme with `⚡ PA` badge
+3. Verify keybindings work in PA session (inherited from base config)
+4. Verify plugins load correctly in PA session