feat(gui): make the Behavior Input node placeable and configurable

src/glider/core/live_signals.py

@@ -59,6 +59,7 @@ class LiveSignalBus:
     def __init__(self) -> None:
         self._lock = threading.RLock()
         self._behavior_subs: list[Callable[[BehaviorEvent], None]] = []
+        self._behaviors: list[str] = []
 
     # -- behavior ---------------------------------------------------------
     def subscribe_behavior(self, callback: Callable[[BehaviorEvent], None]) -> None:
@@ -79,6 +80,23 @@ def unsubscribe_behavior(self, callback: Callable[[BehaviorEvent], None]) -> Non
                     "live bus: behavior subscriber removed (%d left)", len(self._behavior_subs)
                 )
 
+    @property
+    def behaviors(self) -> list[str]:
+        """The loaded model's ordered class vocabulary, or empty if none.
+
+        The bus is already the boundary between vision and the flow, and the
+        label vocabulary is the one piece of vision metadata the flow *editor*
+        needs: a Behavior Input node has to offer the behaviors the model can
+        actually emit. Routing it here keeps the properties panel from reaching
+        into the camera panel to find a worker thread's attribute.
+        """
+        return list(self._behaviors)
+
+    def set_behaviors(self, names: list[str] | None) -> None:
+        """Publish the vocabulary of whatever model is now loaded."""
+        self._behaviors = [str(n) for n in (names or [])]
+        logger.debug("LiveSignalBus: behavior vocabulary set to %s", self._behaviors)
+
     def publish_behavior(self, event: BehaviorEvent) -> int:
         """Deliver *event* to every subscriber. Returns how many were called.
 

src/glider/gui/panels/camera_panel.py

@@ -1602,6 +1602,11 @@ def _on_behavior_ready(self) -> None:
         if worker is None:
             return
         self._preview.set_behavior_vocab(worker.classes)
+        # Also hand the vocabulary to the flow side, so a Behavior Input node's
+        # properties can offer the behaviors this model actually emits instead
+        # of a free-text box where a typo means "never fires".
+        if self._live_signals is not None:
+            self._live_signals.set_behaviors(worker.classes)
         self._behavior_running = True
         self._live_behavior_btn.setText("Stop")
         self._live_behavior_btn.setEnabled(True)

src/glider/gui/panels/node_editor_controller.py

@@ -58,7 +58,7 @@ def node_category_for_type(node_type: str) -> str:
             "StartFunction",
             "EndFunction",
         },
-        "interface": {"Loop", "WaitForInput", "ZoneInput"},
+        "interface": {"Loop", "WaitForInput", "ZoneInput", "BehaviorInput"},
         "hardware": {"Output", "Input", "MotorGovernor", "Maimu"},
     }
 
@@ -161,6 +161,8 @@ def setup_node_ports(self, node_item, node_type: str) -> None:
             "EndFunction": ([">exec"], []),
             "FunctionCall": ([">exec"], [">next"]),
             "ZoneInput": ([], ["Occupied", "Object Count", ">On Enter", ">On Exit"]),
+            "BehaviorInput": ([], ["Active", "Behavior", ">On Enter", ">On Exit"]),
+            "Maimu": ([">exec"], [">exec"]),
         }
 
         inputs, outputs = port_configs.get(nt, ([">in"], [">out"]))
@@ -585,6 +587,53 @@ def _sync_pulse_fields(_=None, combo=mode_combo):
                 note.setWordWrap(True)
                 props_layout.addRow(note)
 
+        elif node_type == "BehaviorInput":
+            self._add_section_header(props_layout, "BEHAVIOR")
+            saved_state = (node_config.state if node_config else None) or {}
+
+            # Editable so a graph can be authored before any model is loaded,
+            # but populated from the loaded model's vocabulary when there is
+            # one -- a mistyped label silently never fires, which is the worst
+            # failure mode available to a closed-loop stimulus.
+            behavior_combo = QComboBox()
+            behavior_combo.setEditable(True)
+            known = self._known_behaviors()
+            if known:
+                behavior_combo.addItems(known)
+            behavior_combo.lineEdit().setPlaceholderText(
+                "behavior label" if known else "start live behavior to list the model's labels"
+            )
+            saved_behavior = saved_state.get("target_behavior", "")
+            behavior_combo.setCurrentText(saved_behavior)
+            behavior_combo.currentTextChanged.connect(
+                lambda txt, nid=node_id: self._on_node_property_changed(
+                    nid, "target_behavior", txt.strip()
+                )
+            )
+            props_layout.addRow("Behavior:", behavior_combo)
+
+            frames_spin = QSpinBox()
+            frames_spin.setRange(1, 300)
+            frames_spin.setSuffix(" frames")
+            frames_spin.setValue(int(saved_state.get("min_frames", 5)))
+            frames_spin.setToolTip(
+                "Consecutive frames carrying the behavior before it counts as "
+                "entered, and the same number without it before it counts as left."
+            )
+            frames_spin.valueChanged.connect(
+                lambda val, nid=node_id: self._on_node_property_changed(nid, "min_frames", val)
+            )
+            props_layout.addRow("Confirm over:", frames_spin)
+
+            note = QLabel(
+                "Per-frame classification is noisy, so a single stray frame must "
+                "not fire hardware. The confirmation delays the trigger: at 30 fps, "
+                "5 frames is about 167 ms on top of inference."
+            )
+            note.setProperty("textRole", "muted")
+            note.setWordWrap(True)
+            props_layout.addRow(note)
+
         elif node_type == "Delay":
             self._add_section_header(props_layout, "CONFIGURATION")
 
@@ -1313,6 +1362,20 @@ def _on_node_device_changed(self, node_id: str, device_id: str) -> None:
 
                 self._update_properties_panel(node_id)
 
+    def _known_behaviors(self) -> list[str]:
+        """Labels the currently loaded behavior model can emit, if any.
+
+        Empty before a model is loaded, which is a normal authoring state and
+        not an error: the combo stays editable so the graph can still be built.
+        """
+        core = getattr(self, "_core", None)
+        bus = getattr(core, "live_signals", None) if core is not None else None
+        try:
+            return list(bus.behaviors) if bus is not None else []
+        except Exception:  # noqa: BLE001 - a missing vocabulary must not break the panel
+            logger.debug("Could not read the behavior vocabulary", exc_info=True)
+            return []
+
     def _on_node_property_changed(self, node_id: str, prop_name: str, value) -> None:
         """Handle property change for a node."""
         session = self._session

src/glider/gui/panels/node_library_panel.py

@@ -173,6 +173,14 @@ def _setup_ui(self):
                 ("Input", "Input", "Read from a device (digital or analog)"),
                 ("Maimu", "Maimu", "Drive a Maimu BLE stimulator: on, off, or a timed pulse"),
             ],
+            "Behavior": [
+                (
+                    "BehaviorInput",
+                    "Behavior Input",
+                    "Trigger on live behavior classification - fires On Enter / On "
+                    "Exit as the animal starts and stops a behavior",
+                ),
+            ],
             "Audio": [
                 ("AudioPlayback", "Audio Playback", "Play an audio file (WAV/MP3)"),
             ],
@@ -186,6 +194,7 @@ def _setup_ui(self):
             "Functions": colors.LIB_FUNCTIONS,
             "Control": colors.LIB_CONTROL,
             "I/O": colors.LIB_IO,
+            "Behavior": colors.LIB_BEHAVIOR,
             "Audio": colors.LIB_AUDIO,
             "Video": colors.LIB_VIDEO,
             "default": colors.BORDER,

src/glider/gui/styles/colors.py

@@ -118,6 +118,7 @@ def qcolor_with_alpha(color: QColor, alpha: float) -> QColor:
 LIB_AUDIO = "#3d1a5f"
 LIB_VIDEO = "#1e3a5f"
 LIB_ZONES = "#4a3a1a"
+LIB_BEHAVIOR = "#5f1a3a"
 
 # === Behavior State Colors (CV-specific, not theme colors) ===
 BEHAVIOR_FREEZE = "#0000FF"