docs: add tmux testing instructions to AGENTS.md

AGENTS.md

@@ -50,6 +50,31 @@ When closing issues via commit:
 - GitHub CLI for issues/PRs
 - Add package labels to issues/PRs: pkg:agent, pkg:ai, pkg:coding-agent, pkg:mom, pkg:pods, pkg:tui, pkg:web-ui
 
+## Testing pi Interactive Mode with tmux
+
+To test pi's TUI in a controlled terminal environment:
+
+```bash
+# Create tmux session with specific dimensions
+tmux new-session -d -s pi-test -x 80 -y 24
+
+# Start pi from source
+tmux send-keys -t pi-test "cd /Users/badlogic/workspaces/pi-mono && ./pi-test.sh" Enter
+
+# Wait for startup, then capture output
+sleep 3 && tmux capture-pane -t pi-test -p
+
+# Send input
+tmux send-keys -t pi-test "your prompt here" Enter
+
+# Send special keys
+tmux send-keys -t pi-test Escape
+tmux send-keys -t pi-test C-o  # ctrl+o
+
+# Cleanup
+tmux kill-session -t pi-test
+```
+
 ## Style
 - Keep answers short and concise
 - No emojis in commits, issues, PR comments, or code