Fallback for existing sandbox and name collision

install.sh

@@ -22,7 +22,27 @@ mkdir -p "$BIN_DIR"
 
 cat > "$SHIM" <<'EOF'
 #!/bin/sh
-exec sbx run -t localhost/opencode-v2:local "$@" opencode
+# sbx run accepts -t/--template only at sandbox creation time; re-running
+# against an existing sandbox with a template fails. So pass the template
+# only when the named sandbox doesn't exist yet.
+TEMPLATE=localhost/opencode-v2:local
+
+# Extract --name VALUE / --name=VALUE from the arguments, if given.
+name=
+prev=
+for arg in "$@"; do
+  [ "$prev" = --name ] && name=$arg
+  case "$arg" in
+    --name=*) name=${arg#--name=} ;;
+  esac
+  prev=$arg
+done
+
+if [ -n "$name" ] && sbx ls -q 2>/dev/null | grep -Fxq -- "$name"; then
+  exec sbx run "$@" opencode
+fi
+
+exec sbx run -t "$TEMPLATE" "$@" opencode
 EOF
 chmod +x "$SHIM"
 echo "==> Installed shim: $SHIM"