diff --git a/start-agent.sh b/start-agent.sh
index fda36c0..170756d 100755
--- a/start-agent.sh
+++ b/start-agent.sh
@@ -1,9 +1,79 @@
 #!/usr/bin/env bash
-# Start or attach to tmux agent session (Claude on-demand)
+# Start, attach, kill, detach, or list tmux agent sessions
+#
+# Usage:
+#   ./start-agent.sh              # attach/create session 1 (default)
+#   ./start-agent.sh 1|2|3        # attach/create session by number
+#   ./start-agent.sh kill [1|2|3] # kill a session
+#   ./start-agent.sh detach [1|2|3] # detach all clients from a session
+#   ./start-agent.sh list         # list all tmux sessions
 
-SESSION_NAME="agent"
 WORKDIR="/workspace"
 
+# ---- Helper: map number to session name ----
+session_name() {
+    case "${1:-1}" in
+        1) echo "agent" ;;
+        2) echo "agent2" ;;
+        3) echo "agent3" ;;
+        *) return 1 ;;
+    esac
+}
+
+# ---- Parse arguments ----
+ACTION="start"
+SESSION_NUM="1"
+
+case "$1" in
+    kill|detach|list)
+        ACTION="$1"
+        SESSION_NUM="${2:-1}"
+        ;;
+    1|2|3|"")
+        ACTION="start"
+        SESSION_NUM="${1:-1}"
+        ;;
+    *)
+        echo "Usage: $0 [1|2|3|kill|detach|list] [1|2|3]"
+        exit 1
+        ;;
+esac
+
+# ---- Handle 'list' early (no session needed) ----
+if [ "$ACTION" = "list" ]; then
+    tmux ls 2>/dev/null || echo "No tmux sessions running."
+    exit 0
+fi
+
+# ---- Resolve session name ----
+SESSION_NAME=$(session_name "$SESSION_NUM")
+if [ -z "$SESSION_NAME" ]; then
+    echo "Invalid session number: $SESSION_NUM (use 1, 2, or 3)"
+    exit 1
+fi
+
+# ---- Handle kill ----
+if [ "$ACTION" = "kill" ]; then
+    if tmux has-session -t "$SESSION_NAME" 2>/dev/null; then
+        tmux kill-session -t "$SESSION_NAME"
+        echo "Killed session: $SESSION_NAME"
+    else
+        echo "Session not found: $SESSION_NAME"
+    fi
+    exit 0
+fi
+
+# ---- Handle detach ----
+if [ "$ACTION" = "detach" ]; then
+    if tmux has-session -t "$SESSION_NAME" 2>/dev/null; then
+        tmux detach-client -s "$SESSION_NAME"
+        echo "Detached all clients from: $SESSION_NAME"
+    else
+        echo "Session not found: $SESSION_NAME"
+    fi
+    exit 0
+fi
+
 # ---- NVM bootstrap (available, not forced) ----
 export NVM_DIR="$HOME/.nvm"
 [ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh"
@@ -39,4 +109,4 @@ tmux split-window -h -t "$SESSION_NAME:1" -c "$WORKDIR"
 
 # ---- Focus left pane & attach ----
 tmux select-pane -t "$SESSION_NAME:1.1"
-tmux attach-session -t "$SESSION_NAME"
\ No newline at end of file
+tmux attach-session -t "$SESSION_NAME"