feat: add npc decision inspector

main.tscn

@@ -101,3 +101,26 @@ theme_override_constants/margin_bottom = 4
 [node name="VillageStatsLabel" type="Label" parent="UI/VillagePanel/MarginContainer" unique_id=1554319259]
 layout_mode = 2
 theme_override_font_sizes/font_size = 10
+
+[node name="NpcInspectorPanel" type="PanelContainer" parent="UI"]
+anchors_preset = 1
+anchor_left = 1.0
+anchor_right = 1.0
+offset_left = -370.0
+offset_top = 20.0
+offset_right = -20.0
+offset_bottom = 330.0
+grow_horizontal = 0
+
+[node name="MarginContainer" type="MarginContainer" parent="UI/NpcInspectorPanel"]
+layout_mode = 2
+theme_override_constants/margin_left = 16
+theme_override_constants/margin_top = 12
+theme_override_constants/margin_right = 16
+theme_override_constants/margin_bottom = 12
+
+[node name="NpcInspectorLabel" type="Label" parent="UI/NpcInspectorPanel/MarginContainer"]
+layout_mode = 2
+theme_override_colors/font_color = Color(0.96, 0.91, 0.78, 1)
+theme_override_font_sizes/font_size = 15
+text = "Villager inspector"

player/npc/NpcVisual.gd

@@ -12,6 +12,9 @@ const DEBUG_LOGS := true
 @export var stuck_timeout := 1.5
 
 @onready var nav_agent: NavigationAgent3D = $NavigationAgent3D
+@onready var body_mesh: MeshInstance3D = $MeshInstance3D
+@onready var profession_prop: MeshInstance3D = $ProfessionProp
+@onready var profession_label: Label3D = $ProfessionLabel
 @onready var carried_food_visual: MeshInstance3D = $CarriedFood
 
 var has_reported_arrival := false
@@ -45,9 +48,66 @@ func setup_from_sim(npc: SimNPC) -> void:
 	npc_name = npc.npc_name
 	profession = npc.profession
 	name = "NPC_%s_%s" % [sim_id, npc_name]
+	_apply_profession_presentation()
 	set_carried_food_visible(npc.get_inventory_amount(SimulationIds.RESOURCE_FOOD) > 0.0)
 
 
+func _apply_profession_presentation() -> void:
+	var definition := SimulationDefinitions.get_profession(profession)
+	if definition == null:
+		profession_label.text = npc_name
+		profession_prop.visible = false
+		return
+
+	var body_material := StandardMaterial3D.new()
+	body_material.albedo_color = definition.visual_color
+	body_material.roughness = 0.82
+	body_mesh.material_override = body_material
+
+	var prop_material := StandardMaterial3D.new()
+	prop_material.albedo_color = definition.prop_color
+	prop_material.roughness = 0.78
+	profession_prop.material_override = prop_material
+	profession_prop.mesh = _create_profession_prop_mesh()
+	profession_prop.visible = profession_prop.mesh != null
+	profession_label.text = "%s\n%s" % [npc_name, definition.display_name]
+
+
+func _create_profession_prop_mesh() -> PrimitiveMesh:
+	profession_prop.position = Vector3(0.48, 0.85, 0.0)
+	profession_prop.rotation_degrees = Vector3.ZERO
+	match profession:
+		SimulationIds.PROFESSION_FARMER:
+			var basket := SphereMesh.new()
+			basket.radius = 0.24
+			basket.height = 0.34
+			return basket
+		SimulationIds.PROFESSION_WOODCUTTER:
+			var tool := BoxMesh.new()
+			tool.size = Vector3(0.12, 0.72, 0.16)
+			profession_prop.position = Vector3(0.48, 0.92, 0.0)
+			profession_prop.rotation_degrees.z = -18.0
+			return tool
+		SimulationIds.PROFESSION_GUARD:
+			var shield := CylinderMesh.new()
+			shield.top_radius = 0.3
+			shield.bottom_radius = 0.3
+			shield.height = 0.12
+			profession_prop.rotation_degrees.x = 90.0
+			return shield
+		SimulationIds.PROFESSION_SCHOLAR:
+			var book := BoxMesh.new()
+			book.size = Vector3(0.42, 0.1, 0.3)
+			return book
+		SimulationIds.PROFESSION_WANDERER:
+			var pack := SphereMesh.new()
+			pack.radius = 0.28
+			pack.height = 0.5
+			profession_prop.position = Vector3(-0.42, 0.86, 0.0)
+			return pack
+	return null
+
+
 func set_carried_food_visible(is_visible: bool) -> void:
 	carried_food_visual.visible = is_visible and not is_dead_visual
 
@@ -179,6 +239,7 @@ func _report_navigation_failure_once() -> void:
 func apply_dead_visual_state() -> void:
 	is_dead_visual = true
 	carried_food_visual.visible = false
+	profession_prop.visible = false
 	path_request_id += 1
 	velocity = Vector3.ZERO
 	current_path = PackedVector3Array()

player/npc/NpcVisual.tscn

@@ -38,6 +38,18 @@ mesh = SubResource("CapsuleMesh_d844k")
 transform = Transform3D(0.15, 0, 0, 0, 0.15, 0, 0, 0, 0.35, 0, 1.2, 0.59052056)
 mesh = SubResource("BoxMesh_d844k")
 
+[node name="ProfessionProp" type="MeshInstance3D" parent="."]
+
+[node name="ProfessionLabel" type="Label3D" parent="."]
+position = Vector3(0, 2.05, 0)
+billboard = 1
+no_depth_test = true
+text = "Villager"
+font_size = 24
+outline_size = 6
+modulate = Color(1, 0.96, 0.82, 1)
+pixel_size = 0.007
+
 [node name="CarriedFood" type="MeshInstance3D" parent="."]
 visible = false
 transform = Transform3D(0.75, 0, 0, 0, 0.75, 0, 0, 0, 0.75, 0.48, 0.7, 0)

simulation/SimulationManager.gd

@@ -8,6 +8,7 @@ signal npc_travel_requested(npc: SimNPC, target_position: Vector3)
 signal npc_inventory_changed(npc: SimNPC, item_id: StringName, amount: float)
 signal economic_event_recorded(event: EconomicEventRecord)
 signal state_restored
+signal npc_decision_recorded(npc: SimNPC, decision: ActionSelectionResult)
 
 var village := SimVillage.new()
 
@@ -24,6 +25,7 @@ var resource_states: Dictionary = {}
 var storage_states: Dictionary = {}
 var economic_events: Array[EconomicEventRecord] = []
 var next_event_id := 0
+var latest_decisions: Dictionary = {}
 var action_selector := ActionSelectionSystem.new()
 var action_executor := ActionExecutionSystem.new()
 var target_resolver := ActionTargetResolver.new()
@@ -111,6 +113,8 @@ func simulate_tick() -> void:
 		):
 			var selection := action_selector.select_action(npc, village)
 			if selection != null:
+				latest_decisions[npc.id] = selection
+				npc_decision_recorded.emit(npc, selection)
 				npc.set_task(selection.action_id, selection.duration_override)
 
 		if old_task != npc.current_task and old_target != &"":
@@ -679,6 +683,10 @@ func get_state_checksum() -> String:
 	return create_state_record().to_json().sha256_text()
 
 
+func get_latest_decision(npc_id: int) -> ActionSelectionResult:
+	return latest_decisions.get(npc_id)
+
+
 func create_state_record() -> SimulationStateRecord:
 	var record := SimulationStateRecord.new()
 	var wander_streams: Array[Dictionary] = []
@@ -747,6 +755,7 @@ func restore_state(record: SimulationStateRecord) -> bool:
 		storage_states[storage_record.get_storage_id()] = storage_record
 	_sync_village_food()
 	economic_events = record.economic_events.duplicate()
+	latest_decisions.clear()
 
 	npcs.clear()
 	for npc_record in record.npcs:

simulation/actions/ActionSelectionResult.gd

@@ -3,8 +3,17 @@ extends RefCounted
 
 var action_id: StringName
 var duration_override := -1.0
+var reason: String
+var scores: Dictionary
 
 
-func _init(selected_action_id: StringName, selected_duration_override: float = -1.0) -> void:
+func _init(
+	selected_action_id: StringName,
+	selected_duration_override: float = -1.0,
+	decision_reason: String = "",
+	decision_scores: Dictionary = {}
+) -> void:
 	action_id = selected_action_id
 	duration_override = selected_duration_override
+	reason = decision_reason
+	scores = decision_scores.duplicate(true)

simulation/actions/ActionSelectionSystem.gd

@@ -7,24 +7,40 @@ func select_action(npc: SimNPC, village: SimVillage) -> ActionSelectionResult:
 		return null
 	if npc.is_starving:
 		if npc.get_inventory_amount(SimulationIds.RESOURCE_FOOD) >= 1.0:
-			return ActionSelectionResult.new(SimulationIds.ACTION_EAT, 1.0)
+			return ActionSelectionResult.new(
+				SimulationIds.ACTION_EAT, 1.0, "Starving and carrying food"
+			)
 		if village.food > 0:
-			return ActionSelectionResult.new(SimulationIds.ACTION_WITHDRAW_FOOD, 1.0)
-		return ActionSelectionResult.new(SimulationIds.ACTION_GATHER_FOOD, 4.0)
+			return ActionSelectionResult.new(
+				SimulationIds.ACTION_WITHDRAW_FOOD, 1.0, "Starving; pantry has food"
+			)
+		return ActionSelectionResult.new(
+			SimulationIds.ACTION_GATHER_FOOD, 4.0, "Starving; pantry is empty"
+		)
 	if npc.hunger > 75.0:
 		if npc.get_inventory_amount(SimulationIds.RESOURCE_FOOD) >= 1.0:
-			return ActionSelectionResult.new(SimulationIds.ACTION_EAT)
+			return ActionSelectionResult.new(
+				SimulationIds.ACTION_EAT, -1.0, "Hungry and carrying food"
+			)
 		if village.food > 0:
-			return ActionSelectionResult.new(SimulationIds.ACTION_WITHDRAW_FOOD)
-		return ActionSelectionResult.new(SimulationIds.ACTION_GATHER_FOOD)
+			return ActionSelectionResult.new(
+				SimulationIds.ACTION_WITHDRAW_FOOD, -1.0, "Hungry; pantry has food"
+			)
+		return ActionSelectionResult.new(
+			SimulationIds.ACTION_GATHER_FOOD, -1.0, "Hungry; pantry is empty"
+		)
 	if npc.get_inventory_amount(SimulationIds.RESOURCE_FOOD) > 0.0:
-		return ActionSelectionResult.new(SimulationIds.ACTION_DEPOSIT_FOOD)
+		return ActionSelectionResult.new(
+			SimulationIds.ACTION_DEPOSIT_FOOD, -1.0, "Carrying food for storage"
+		)
 	if npc.energy < 25.0:
-		return ActionSelectionResult.new(SimulationIds.ACTION_REST)
-	return ActionSelectionResult.new(_choose_best_work_action(npc, village))
+		return ActionSelectionResult.new(
+			SimulationIds.ACTION_REST, -1.0, "Energy is below the rest threshold"
+		)
+	return _choose_best_work_action(npc, village)
 
 
-func _choose_best_work_action(npc: SimNPC, village: SimVillage) -> StringName:
+func _choose_best_work_action(npc: SimNPC, village: SimVillage) -> ActionSelectionResult:
 	var scores := {
 		SimulationIds.ACTION_GATHER_FOOD:
 		_calculate_score(
@@ -80,7 +96,9 @@ func _choose_best_work_action(npc: SimNPC, village: SimVillage) -> StringName:
 		if score > best_score:
 			best_action = action_id
 			best_score = score
-	return best_action
+	return ActionSelectionResult.new(
+		best_action, -1.0, "Highest current work utility", scores
+	)
 
 
 func _calculate_score(

simulation/definitions/ProfessionDefinition.gd

@@ -3,6 +3,8 @@ extends Resource
 
 @export var profession_id: StringName
 @export var display_name: String
+@export var visual_color := Color.WHITE
+@export var prop_color := Color(0.35, 0.25, 0.15, 1.0)
 
 
 func validate() -> Array[String]:
@@ -11,4 +13,6 @@ func validate() -> Array[String]:
 		errors.append("profession_id is empty")
 	if display_name.is_empty():
 		errors.append("display_name is empty for '%s'" % profession_id)
+	if visual_color.a <= 0.0:
+		errors.append("visual_color is transparent for '%s'" % profession_id)
 	return errors

simulation/definitions/professions/farmer.tres

@@ -6,3 +6,5 @@
 script = ExtResource("1")
 profession_id = &"farmer"
 display_name = "Farmer"
+visual_color = Color(0.36, 0.62, 0.28, 1)
+prop_color = Color(0.65, 0.45, 0.2, 1)

simulation/definitions/professions/guard.tres

@@ -6,3 +6,5 @@
 script = ExtResource("1")
 profession_id = &"guard"
 display_name = "Guard"
+visual_color = Color(0.25, 0.42, 0.68, 1)
+prop_color = Color(0.72, 0.75, 0.78, 1)

simulation/definitions/professions/scholar.tres

@@ -6,3 +6,5 @@
 script = ExtResource("1")
 profession_id = &"scholar"
 display_name = "Scholar"
+visual_color = Color(0.52, 0.34, 0.68, 1)
+prop_color = Color(0.78, 0.66, 0.28, 1)

simulation/definitions/professions/wanderer.tres

@@ -6,3 +6,5 @@
 script = ExtResource("1")
 profession_id = &"wanderer"
 display_name = "Wanderer"
+visual_color = Color(0.72, 0.57, 0.3, 1)
+prop_color = Color(0.38, 0.28, 0.19, 1)

simulation/definitions/professions/woodcutter.tres

@@ -6,3 +6,5 @@
 script = ExtResource("1")
 profession_id = &"woodcutter"
 display_name = "Woodcutter"
+visual_color = Color(0.67, 0.34, 0.2, 1)
+prop_color = Color(0.34, 0.22, 0.14, 1)

tests/action_system_boundaries_test.gd

@@ -53,6 +53,17 @@ func _test_selection_and_execution_are_separate() -> void:
 		selection.action_id == SimulationIds.ACTION_WITHDRAW_FOOD,
 		"Selection should independently choose food retrieval"
 	)
+	_check(
+		not selection.reason.is_empty(),
+		"Selection should expose the real decision branch for presentation"
+	)
+	npc.hunger = 20.0
+	npc.energy = 80.0
+	var work_selection := selector.select_action(npc, village)
+	_check(
+		work_selection.scores.size() == 4,
+		"Ordinary work selection should expose all compared utility scores"
+	)
 
 
 func _test_target_resolution_and_travel_are_separate() -> void:

tests/npc_visual_lifecycle_test.gd

@@ -16,10 +16,38 @@ func _run() -> void:
 
 	var manager: Node = main_scene.get_node("SimulationManager")
 	var view: Node = main_scene.get_node("WorldViewManager")
+	var ui: CanvasLayer = main_scene.get_node("UI")
 	manager.set_process(false)
 	var npc: SimNPC = manager.npcs[0]
 	var visual: Node3D = view.active_npc_visuals[npc.id]
 	visual.set_physics_process(false)
+	var profession_definition := SimulationDefinitions.get_profession(npc.profession)
+	var body: MeshInstance3D = visual.get_node("MeshInstance3D")
+	_check(
+		body.material_override.albedo_color == profession_definition.visual_color,
+		"NPC body color should come from its profession definition"
+	)
+	_check(
+		visual.get_node("ProfessionProp").mesh != null
+		and profession_definition.display_name in visual.get_node("ProfessionLabel").text,
+		"NPC visual should expose a profession prop and readable label"
+	)
+	var test_decision := ActionSelectionResult.new(
+		SimulationIds.ACTION_GATHER_FOOD,
+		-1.0,
+		"Test shortage reason",
+		{SimulationIds.ACTION_GATHER_FOOD: 4.5}
+	)
+	manager.latest_decisions[npc.id] = test_decision
+	manager.emit_signal("npc_decision_recorded", npc, test_decision)
+	var inspector_label: Label = ui.get_node(
+		"NpcInspectorPanel/MarginContainer/NpcInspectorLabel"
+	)
+	_check(
+		"Test shortage reason" in inspector_label.text
+		and npc.npc_name in inspector_label.text,
+		"NPC inspector should show the selected villager's real decision reason"
+	)
 	var carried_food: MeshInstance3D = visual.get_node("CarriedFood")
 	_check(not carried_food.visible, "NPC should begin without a carried-food prop")
 	npc.add_inventory(SimulationIds.RESOURCE_FOOD, 1.0)

tests/simulation_definitions_test.gd

@@ -38,11 +38,19 @@ func _test_registry_integrity() -> void:
 
 	var profession_ids := SimulationDefinitions.get_profession_ids()
 	_check(profession_ids.size() == 5, "Registry should contain all five prototype professions")
+	var profession_colors := {}
 	for profession_id in profession_ids:
+		var profession := SimulationDefinitions.get_profession(profession_id)
 		_check(
-			SimulationDefinitions.get_profession(profession_id) != null,
+			profession != null,
 			"Profession lookup should return '%s'" % profession_id
 		)
+		if profession != null:
+			profession_colors[profession.visual_color.to_html()] = true
+	_check(
+		profession_colors.size() == profession_ids.size(),
+		"Each profession should have a distinct definition-backed visual color"
+	)
 
 
 func _test_definition_backed_behavior() -> void:

world/ui/ui.gd

@@ -5,6 +5,10 @@ const DEBUG_LOGS := false
 @export var simulation_manager: Node
 
 @onready var village_stats_label: Label = $VillagePanel/MarginContainer/VillageStatsLabel
+@onready var npc_inspector_label: Label = $NpcInspectorPanel/MarginContainer/NpcInspectorLabel
+
+var selected_npc_index := 0
+var inspector_refresh_accumulator := 0.0
 
 
 func _ready() -> void:
@@ -16,9 +20,34 @@ func _ready() -> void:
 		simulation_manager.village_changed.connect(_on_village_changed)
 	else:
 		push_error("VillageUI: SimulationManager has no village_changed signal")
+	if simulation_manager.has_signal("npc_decision_recorded"):
+		simulation_manager.npc_decision_recorded.connect(_on_npc_decision_recorded)
+	else:
+		push_error("VillageUI: SimulationManager has no npc_decision_recorded signal")
+	if simulation_manager.has_signal("state_restored"):
+		simulation_manager.state_restored.connect(_on_state_restored)
 
 	if "village" in simulation_manager:
 		_on_village_changed(simulation_manager.village)
+	_refresh_npc_inspector()
+
+
+func _process(delta: float) -> void:
+	inspector_refresh_accumulator += delta
+	if inspector_refresh_accumulator < 0.25:
+		return
+	inspector_refresh_accumulator = 0.0
+	_refresh_npc_inspector()
+
+
+func _unhandled_key_input(event: InputEvent) -> void:
+	if not event is InputEventKey or not event.pressed or event.echo:
+		return
+	if event.keycode != KEY_TAB or simulation_manager.npcs.is_empty():
+		return
+	selected_npc_index = (selected_npc_index + 1) % simulation_manager.npcs.size()
+	_refresh_npc_inspector()
+	get_viewport().set_input_as_handled()
 
 
 func _on_village_changed(village: SimVillage) -> void:
@@ -47,3 +76,73 @@ func _on_village_changed(village: SimVillage) -> void:
 			village.knowledge_modifier
 		]
 	)
+
+
+func _on_npc_decision_recorded(_npc: SimNPC, _decision: ActionSelectionResult) -> void:
+	_refresh_npc_inspector()
+
+
+func _on_state_restored() -> void:
+	selected_npc_index = 0
+	_refresh_npc_inspector()
+
+
+func _refresh_npc_inspector() -> void:
+	if simulation_manager == null or simulation_manager.npcs.is_empty():
+		npc_inspector_label.text = "No villagers available"
+		return
+	selected_npc_index = clampi(selected_npc_index, 0, simulation_manager.npcs.size() - 1)
+	var npc: SimNPC = simulation_manager.npcs[selected_npc_index]
+	var profession_definition := SimulationDefinitions.get_profession(npc.profession)
+	var profession_name := String(npc.profession)
+	if profession_definition != null:
+		profession_name = profession_definition.display_name
+	var action_name := _get_action_name(npc.current_task)
+	var destination_name := "Resolving"
+	if not npc.target_id.is_empty():
+		destination_name = String(npc.target_id)
+	var decision: ActionSelectionResult = simulation_manager.get_latest_decision(npc.id)
+	var reason_text := "Awaiting the next decision"
+	var score_text := ""
+	if decision != null:
+		reason_text = decision.reason
+		var score_keys: Array = decision.scores.keys()
+		score_keys.sort()
+		var score_rows: Array[String] = []
+		for action_id in score_keys:
+			score_rows.append(
+				"%s %.2f" % [_get_action_name(StringName(action_id)), float(decision.scores[action_id])]
+			)
+		if not score_rows.is_empty():
+			score_text = "\n\nUtility\n" + "\n".join(score_rows)
+	npc_inspector_label.text = (
+		"%s  ·  %s\n"
+		+ "Task: %s (%s)\n"
+		+ "Destination: %s\n"
+		+ "Hunger: %.0f   Energy: %.0f\n"
+		+ "Carrying food: %.0f\n\n"
+		+ "Why\n%s%s\n\n"
+		+ "[Tab] Next villager"
+	) % [
+		npc.npc_name,
+		profession_name,
+		action_name,
+		npc.task_state,
+		destination_name,
+		npc.hunger,
+		npc.energy,
+		npc.get_inventory_amount(SimulationIds.RESOURCE_FOOD),
+		reason_text,
+		score_text
+	]
+
+
+func _get_action_name(action_id: StringName) -> String:
+	if action_id == SimulationIds.ACTION_IDLE:
+		return "Idle"
+	if action_id == SimulationIds.ACTION_DEAD:
+		return "Dead"
+	var definition := SimulationDefinitions.get_action(action_id)
+	if definition != null:
+		return definition.display_name
+	return String(action_id).capitalize()