diff --git a/src/model/humanoid_map.gd b/src/model/humanoid_map.gd
new file mode 100644
index 0000000..891460c
--- /dev/null
+++ b/src/model/humanoid_map.gd
@@ -0,0 +1,163 @@
+class_name HumanoidMap
+extends RefCounted
+
+## VRM humanoid 骨骼名映射
+##
+## VRM 规范定义了 20+ 根 humanoid 骨骼，但**不要求**节点名固定，
+## 因此需要按名字猜测。本表覆盖三类常见命名：
+##   1. VRoid Studio：J_Bip_C_Hips / J_Bip_L_UpperArm / J_Bip_L_LowerLeg …
+##   2. VRM 0.x 通用：Hips / LeftArm / LeftForeArm / LeftUpLeg / LeftLeg …
+##   3. Mixamo 重定向：mixamorig:LeftArm / mixamorig:LeftForeArm …
+##
+## 匹配策略：归一化（小写 + 去分隔符）→ 剥掉已知前缀 → 与候选集**精确**比较。
+## 注意 VRoid 的 J_Bip_C_* 中 C 表示「中心骨」，归一化后残留前导 c
+## （如 J_Bip_C_Hips → "chips"），因此中心骨候选里额外列出 c 开头的写法。
+## 只剥离 J_Bip / mixamorig / Bip01 —— 故意不剥离 J_Aim_ / J_Roll_ / J_Sec_，
+## 因为 VRoid 用这些前缀标记扭转辅助骨（如 J_Aim_L_UpperLeg），
+## 若一并剥离会与真正的 J_Bip_L_UpperLeg 撞名，导致驱动到错误的骨骼上。
+
+## 需要驱动的人形骨骼（顺序即层级，父在前）
+const HUMANOID_BONES: Array[String] = [
+	"hips",
+	"spine",
+	"chest",
+	"upperChest",
+	"neck",
+	"head",
+	"leftShoulder",
+	"leftUpperArm",
+	"leftLowerArm",
+	"leftHand",
+	"rightShoulder",
+	"rightUpperArm",
+	"rightLowerArm",
+	"rightHand",
+	"leftUpperLeg",
+	"leftLowerLeg",
+	"leftFoot",
+	"leftToes",
+	"rightUpperLeg",
+	"rightLowerLeg",
+	"rightFoot",
+	"rightToes",
+]
+
+## 归一化时剥离的前缀。
+## 必须是**归一化之后**的形态（小写、无下划线/冒号）——
+## 早期版本写成 "j_bip" 而 normalize() 已经去掉了下划线，
+## 导致 begins_with 永远不成立，VRoid 模型全覆盖率为 0。
+const STRIPPABLE_PREFIXES: Array[String] = [
+	"jbip",
+	"mixamorig",
+	"bip001",
+	"bip01",
+]
+
+## 规范化骨骼名的小写形态（去掉分隔符，但保留前缀以便判断）
+## 例如 "J_Bip_L_UpperArm" → "jbiplupperarm"
+static func normalize(node_name: String) -> String:
+	var lower := node_name.to_lower()
+	var out := ""
+	for i in lower.length():
+		var c := lower[i]
+		if (c >= "a" and c <= "z") or (c >= "0" and c <= "9"):
+			out += c
+	return out
+
+
+## 去掉可剥离前缀后的形态
+static func strip_prefix(normalized: String) -> String:
+	for prefix in STRIPPABLE_PREFIXES:
+		if normalized.begins_with(prefix):
+			return normalized.substr(prefix.length())
+	return normalized
+
+
+## 生成用于比较的形态集合：
+##   compact  —— left/right 缩写为 l/r："leftupperarm" → "lupperarm"
+##   expanded —— 首字母 l/r 展开为 left/right："lupperarm" → "leftupperarm"
+static func variants(node_name: String) -> PackedStringArray:
+	var base := strip_prefix(normalize(node_name))
+	var out := PackedStringArray()
+	out.append(base)
+
+	var compact := base
+	if base.begins_with("left"):
+		compact = "l" + base.substr(4)
+	elif base.begins_with("right"):
+		compact = "r" + base.substr(5)
+	out.append(compact)
+
+	var expanded := base
+	if base.begins_with("l") and not base.begins_with("left"):
+		expanded = "left" + base.substr(1)
+	elif base.begins_with("r") and not base.begins_with("right"):
+		expanded = "right" + base.substr(1)
+	out.append(expanded)
+
+	return out
+
+
+## 每个 canonical 骨骼的候选名（全部为归一化后的形态，含 compact 与 expanded 写法）
+const CANDIDATES := {
+	"hips": ["chips", "hips", "hip", "pelvis", "root"],
+	"spine": ["cspine", "spine", "spine1", "spinemid"],
+	"chest": ["cchest", "chest", "spine2", "spineupper"],
+	"upperChest": ["cupperchest", "upperchest", "chest2", "spine3"],
+	"neck": ["cneck", "neck", "neck1"],
+	"head": ["chead", "head"],
+	"leftShoulder": ["lshoulder", "leftshoulder", "shoulderl", "shoulderleft", "claviclel", "lclavicle"],
+	"leftUpperArm": ["lupperarm", "leftupperarm", "larm", "leftarm", "luparm"],
+	"leftLowerArm": ["llowerarm", "leftlowerarm", "lforearm", "leftforearm", "lelbow"],
+	"leftHand": ["lhand", "lefthand", "lwrist", "leftwrist"],
+	"rightShoulder": ["rshoulder", "rightshoulder", "shoulderr", "shoulderright", "clavicler", "rclavicle"],
+	"rightUpperArm": ["rupperarm", "rightupperarm", "rarm", "rightarm", "ruparm"],
+	"rightLowerArm": ["rlowerarm", "rightlowerarm", "rforearm", "rightforearm", "relbow"],
+	"rightHand": ["rhand", "righthand", "rwrist", "rightwrist"],
+	"leftUpperLeg": ["lupperleg", "leftupperleg", "lthigh", "leftthigh", "lupleg", "lhip", "lefthip"],
+	"leftLowerLeg": ["llowerleg", "leftlowerleg", "lleg", "leftleg", "lshin", "leftshin", "lknee", "leftknee"],
+	"leftFoot": ["lfoot", "leftfoot", "lankle", "leftankle"],
+	"leftToes": ["ltoes", "lefttoes", "ltoe", "lefttoe", "ltoebase", "lefttoebase"],
+	"rightUpperLeg": ["rupperleg", "rightupperleg", "rthigh", "rightthigh", "rupleg", "rhip", "righthip"],
+	"rightLowerLeg": ["rlowerleg", "rightlowerleg", "rleg", "rightleg", "rshin", "rightshin", "rknee", "rightknee"],
+	"rightFoot": ["rfoot", "rightfoot", "rankle", "rightankle"],
+	"rightToes": ["rtoes", "righttoes", "rtoe", "righttoe", "rtoebase", "righttoebase"],
+}
+
+
+## 在骨骼名列表中查找 humanoid 骨骼
+## 返回 { canonical_name: bone_index }；未找到的键不存在
+static func match_bones(bone_names: PackedStringArray) -> Dictionary:
+	# 先建立 normalized-variant → bone_index 的索引
+	var index := {}
+	for i in bone_names.size():
+		var variants := variants(bone_names[i])
+		for v in variants:
+			# 先出现的优先（骨骼树按前序排列，真正的 humanoid 骨通常更靠前）
+			if not index.has(v):
+				index[v] = i
+
+	var result := {}
+	for canonical in HUMANOID_BONES:
+		var candidates: Array = CANDIDATES.get(canonical, [])
+		for candidate in candidates:
+			if index.has(candidate):
+				result[canonical] = index[candidate]
+				break
+	return result
+
+
+## 映射覆盖率，用于日志与 UI 提示
+static func coverage(matched: Dictionary) -> float:
+	if HUMANOID_BONES.is_empty():
+		return 0.0
+	return float(matched.size()) / float(HUMANOID_BONES.size())
+
+
+## 缺失的骨骼名（用于诊断「模型不受支持」）
+static func missing_bones(matched: Dictionary) -> PackedStringArray:
+	var out := PackedStringArray()
+	for canonical in HUMANOID_BONES:
+		if not matched.has(canonical):
+			out.append(canonical)
+	return out
diff --git a/src/model/humanoid_map.gd.uid b/src/model/humanoid_map.gd.uid
new file mode 100644
index 0000000..b4ddb6a
--- /dev/null
+++ b/src/model/humanoid_map.gd.uid
@@ -0,0 +1 @@
+uid://b538smw833qym
diff --git a/src/model/vrm_loader.gd b/src/model/vrm_loader.gd
new file mode 100644
index 0000000..e84135e
--- /dev/null
+++ b/src/model/vrm_loader.gd
@@ -0,0 +1,153 @@
+class_name VrmLoader
+extends RefCounted
+
+## T-WIN-005：VRM 模型加载
+##
+## 实现选型说明（与文档 §5.1 的差异，已在 README 与任务文档中记录）：
+## 文档选型为 godot-vrm（V-Sekai）GDExtension，但该仓库**不发布任何预编译产物**
+## （无 GitHub Release，仅源码，需用 godot-cpp 本地编译原生库）。
+## 这会同时破坏「Linux 上导出 Windows exe」的 T-WIN-011 验收路径。
+##
+## 因此本实现改用 **Godot 内置 GLTFDocument** —— VRM 本身就是 glTF 2.0 二进制容器：
+##   - 网格 / 蒙皮 / Skeleton3D 由内置导入器完整解析（实测 154 骨骼 VRoid 模型 OK）
+##   - VRM 扩展（extensions.VRM / extensions.VRMC_vrm）可直接从 GLTFState.json 读取
+##   - humanoid 骨骼按名字映射（见 HumanoidMap），不依赖 VRM 扩展
+## 好处：零原生依赖、可无头测试、跨平台导出不受限。
+## 若日后接入 godot-vrm，只需替换本文件的 load_from_file 实现，接口不变。
+
+const HumanoidMap = preload("res://src/model/humanoid_map.gd")
+
+
+class VrmModel extends RefCounted:
+	## 生成出来的场景根节点（未加入树，调用方负责 add_child）
+	var root: Node3D = null
+	var skeleton: Skeleton3D = null
+	## canonical humanoid 名 → 骨骼下标
+	var bones: Dictionary = {}
+	## 原始 VRM 版本字符串，如 "1.0" / "0.0"；非 VRM 为 ""
+	var vrm_version: String = ""
+	## 是否识别为 VRM（含 VRM 扩展）
+	var is_vrm: bool = false
+	var mesh_count: int = 0
+	var bone_count: int = 0
+	var available: bool = false
+	var error: String = ""
+
+	func coverage() -> float:
+		return HumanoidMap.coverage(bones)
+
+	func missing_bones() -> PackedStringArray:
+		return HumanoidMap.missing_bones(bones)
+
+	## 是否具备驱动 33 点所需的最小骨骼集合
+	func is_drivable() -> bool:
+		var required := [
+			"hips", "spine", "neck", "head",
+			"leftUpperArm", "leftLowerArm", "leftHand",
+			"rightUpperArm", "rightLowerArm", "rightHand",
+			"leftUpperLeg", "leftLowerLeg", "leftFoot",
+			"rightUpperLeg", "rightLowerLeg", "rightFoot",
+		]
+		for name in required:
+			if not bones.has(name):
+				return false
+		return true
+
+	func bone_index(canonical: String) -> int:
+		return int(bones.get(canonical, -1))
+
+	## 释放生成的场景（切换模型时必须调用，否则会泄漏）
+	func dispose() -> void:
+		if root != null and is_instance_valid(root):
+			root.free()
+		root = null
+		skeleton = null
+		bones.clear()
+		available = false
+
+
+## 从文件加载 VRM / glTF
+static func load_from_file(path: String) -> VrmModel:
+	var model := VrmModel.new()
+
+	if not FileAccess.file_exists(path):
+		model.error = "文件不存在：%s" % path
+		return model
+
+	var document := GLTFDocument.new()
+	var state := GLTFState.new()
+	var err := document.append_from_file(path, state)
+	if err != OK:
+		model.error = "glTF/VRM 解析失败：%s（%s）" % [error_string(err), path]
+		return model
+
+	var scene: Node = document.generate_scene(state)
+	if scene == null:
+		model.error = "无法从 %s 生成场景" % path
+		return model
+
+	if not (scene is Node3D):
+		scene.free()
+		model.error = "模型根节点不是 Node3D"
+		return model
+
+	model.root = scene as Node3D
+	model.skeleton = find_skeleton(model.root)
+	model.mesh_count = count_meshes(model.root)
+
+	var extension_info := detect_vrm_version(state.json)
+	model.is_vrm = extension_info["is_vrm"]
+	model.vrm_version = extension_info["version"]
+
+	if model.skeleton == null:
+		model.error = "模型中不含 Skeleton3D，无法驱动"
+		model.available = true
+		return model
+
+	model.bone_count = model.skeleton.get_bone_count()
+	var names := PackedStringArray()
+	for i in model.bone_count:
+		names.append(model.skeleton.get_bone_name(i))
+	model.bones = HumanoidMap.match_bones(names)
+
+	model.available = true
+	return model
+
+
+## 从 glTF JSON 读取 VRM 版本
+## 契约 model-formats.md §1：extensions.VRMC_vrm → 1.0；extensions.VRM → 0.x
+static func detect_vrm_version(json: Dictionary) -> Dictionary:
+	var extensions: Dictionary = json.get("extensions", {})
+	if extensions.has("VRMC_vrm"):
+		var spec: Dictionary = extensions["VRMC_vrm"]
+		return {"is_vrm": true, "version": str(spec.get("specVersion", "1.0"))}
+	if extensions.has("VRM"):
+		var spec0: Dictionary = extensions["VRM"]
+		var version := str(spec0.get("specVersion", spec0.get("exporterVersion", "0.x")))
+		return {"is_vrm": true, "version": version}
+	return {"is_vrm": false, "version": ""}
+
+
+static func find_skeleton(node: Node) -> Skeleton3D:
+	if node is Skeleton3D:
+		return node as Skeleton3D
+	for child in node.get_children():
+		var found := find_skeleton(child)
+		if found != null:
+			return found
+	return null
+
+
+static func count_meshes(node: Node) -> int:
+	var total := 1 if node is MeshInstance3D else 0
+	for child in node.get_children():
+		total += count_meshes(child)
+	return total
+
+
+## 从服务端下载的模型文件落到 user:// 缓存后的本地路径
+static func cache_path_for(model_id: int, file_url: String) -> String:
+	var extension := file_url.get_extension()
+	if extension == "":
+		extension = "vrm"
+	return "user://models/%d.%s" % [model_id, extension]
diff --git a/src/model/vrm_loader.gd.uid b/src/model/vrm_loader.gd.uid
new file mode 100644
index 0000000..422f1a1
--- /dev/null
+++ b/src/model/vrm_loader.gd.uid
@@ -0,0 +1 @@
+uid://cv6yuyhh6k5s6
diff --git a/tests/test_vrm_loader.gd b/tests/test_vrm_loader.gd
new file mode 100644
index 0000000..23bc7ff
--- /dev/null
+++ b/tests/test_vrm_loader.gd
@@ -0,0 +1,183 @@
+extends TestCase
+
+## T-WIN-005：VRM 加载与 humanoid 骨骼映射
+##
+## 分两部分：
+##   1. 纯逻辑：HumanoidMap 对三类命名规范的识别（总是运行）
+##   2. 真实模型：加载真实 .vrm 并检查绑定结果（找不到模型文件时跳过）
+##
+## 真实模型不入库（许可证原因），由开发者放在 _scratch/sample.vrm，
+## 或通过 --vrm=<路径> 命令行参数指定。
+
+const HumanoidMap = preload("res://src/model/humanoid_map.gd")
+const VrmLoader = preload("res://src/model/vrm_loader.gd")
+
+const CANDIDATE_PATHS := [
+	"res://_scratch/sample.vrm",
+	"user://models/sample.vrm",
+]
+
+
+func _find_model_path() -> String:
+	for path in CANDIDATE_PATHS:
+		if FileAccess.file_exists(path):
+			return path
+	for arg in OS.get_cmdline_user_args():
+		if arg.begins_with("--vrm="):
+			var path := arg.substr(6)
+			if FileAccess.file_exists(path):
+				return path
+	return ""
+
+
+# ---------------- 纯逻辑：命名规范识别 ----------------
+
+func test_vroid_naming_is_recognized() -> void:
+	var names := PackedStringArray([
+		"J_Bip_C_Hips", "J_Bip_C_Spine", "J_Bip_C_Chest", "J_Bip_C_UpperChest",
+		"J_Bip_C_Neck", "J_Bip_C_Head",
+		"J_Bip_L_Shoulder", "J_Bip_L_UpperArm", "J_Bip_L_LowerArm", "J_Bip_L_Hand",
+		"J_Bip_R_Shoulder", "J_Bip_R_UpperArm", "J_Bip_R_LowerArm", "J_Bip_R_Hand",
+		"J_Bip_L_UpperLeg", "J_Bip_L_LowerLeg", "J_Bip_L_Foot", "J_Bip_L_ToeBase",
+		"J_Bip_R_UpperLeg", "J_Bip_R_LowerLeg", "J_Bip_R_Foot", "J_Bip_R_ToeBase",
+	])
+	var matched := HumanoidMap.match_bones(names)
+	eq(matched.size(), HumanoidMap.HUMANOID_BONES.size(), "VRoid 命名全部 22 根骨骼均被识别")
+	eq(int(matched.get("hips", -1)), 0, "hips 命中 J_Bip_C_Hips")
+	eq(int(matched.get("leftUpperArm", -1)), 7, "leftUpperArm 命中 J_Bip_L_UpperArm")
+	eq(int(matched.get("leftLowerLeg", -1)), 15, "leftLowerLeg 命中 J_Bip_L_LowerLeg")
+	eq(int(matched.get("rightToes", -1)), 21, "rightToes 命中 J_Bip_R_ToeBase")
+	almost(HumanoidMap.coverage(matched), 1.0, 1e-6, "覆盖率 100%")
+
+
+func test_vrm_0x_generic_naming_is_recognized() -> void:
+	var names := PackedStringArray([
+		"Hips", "Spine", "Chest", "Neck", "Head",
+		"LeftShoulder", "LeftArm", "LeftForeArm", "LeftHand",
+		"RightShoulder", "RightArm", "RightForeArm", "RightHand",
+		"LeftUpLeg", "LeftLeg", "LeftFoot", "LeftToeBase",
+		"RightUpLeg", "RightLeg", "RightFoot", "RightToeBase",
+	])
+	var matched := HumanoidMap.match_bones(names)
+	eq(int(matched.get("hips", -1)), 0, "hips 命中 Hips")
+	eq(int(matched.get("leftUpperArm", -1)), 6, "leftUpperArm 命中 LeftArm")
+	eq(int(matched.get("leftLowerArm", -1)), 7, "leftLowerArm 命中 LeftForeArm")
+	eq(int(matched.get("leftUpperLeg", -1)), 13, "leftUpperLeg 命中 LeftUpLeg")
+	eq(int(matched.get("leftLowerLeg", -1)), 14, "leftLowerLeg 命中 LeftLeg")
+	eq(int(matched.get("leftToes", -1)), 16, "leftToes 命中 LeftToeBase")
+
+
+func test_mixamo_naming_is_recognized() -> void:
+	var names := PackedStringArray([
+		"mixamorig:Hips", "mixamorig:Spine", "mixamorig:Spine1", "mixamorig:Neck", "mixamorig:Head",
+		"mixamorig:LeftShoulder", "mixamorig:LeftArm", "mixamorig:LeftForeArm", "mixamorig:LeftHand",
+		"mixamorig:RightShoulder", "mixamorig:RightArm", "mixamorig:RightForeArm", "mixamorig:RightHand",
+		"mixamorig:LeftUpLeg", "mixamorig:LeftLeg", "mixamorig:LeftFoot", "mixamorig:LeftToeBase",
+		"mixamorig:RightUpLeg", "mixamorig:RightLeg", "mixamorig:RightFoot", "mixamorig:RightToeBase",
+	])
+	var matched := HumanoidMap.match_bones(names)
+	eq(int(matched.get("leftUpperArm", -1)), 6, "Mixamo 前缀被剥离，leftUpperArm 命中 LeftArm")
+	eq(int(matched.get("rightUpperLeg", -1)), 17, "rightUpperLeg 命中 RightUpLeg")
+
+
+func test_vroid_helper_bones_do_not_shadow_real_bones() -> void:
+	# VRoid 的扭转辅助骨：J_Aim_L_UpperLeg 等。若错误地剥离 j_aim 前缀，
+	# 它会与真正的 J_Bip_L_UpperLeg 撞名并把动作驱动到错误的骨骼上。
+	var names := PackedStringArray([
+		"J_Bip_C_Hips",
+		"J_Aim_L_UpperLeg", "J_Roll_L_UpperLeg", "J_Sec_L_TopsUpperLegBack",
+		"J_Bip_L_UpperLeg",
+		"J_Aim_R_UpperLeg", "J_Bip_R_UpperLeg",
+	])
+	var matched := HumanoidMap.match_bones(names)
+	eq(int(matched.get("leftUpperLeg", -1)), 4, "leftUpperLeg 命中真正的 J_Bip_L_UpperLeg，而非 J_Aim/J_Roll")
+	eq(int(matched.get("rightUpperLeg", -1)), 6, "rightUpperLeg 命中 J_Bip_R_UpperLeg")
+
+
+func test_unmapped_bones_are_reported() -> void:
+	var names := PackedStringArray(["Hips", "Neck"])
+	var matched := HumanoidMap.match_bones(names)
+	var missing := HumanoidMap.missing_bones(matched)
+	ok(missing.size() > 0, "缺失骨骼被列出", "缺失 %d 根" % missing.size())
+	ok(missing.has("leftHand"), "leftHand 被列为缺失")
+	is_false(missing.has("hips"), "已命中的 hips 不出现在缺失列表")
+
+
+func test_coverage_reflects_match_ratio() -> void:
+	var full := HumanoidMap.match_bones(PackedStringArray(HumanoidMap.HUMANOID_BONES))
+	var partial := HumanoidMap.match_bones(PackedStringArray(["Hips", "Neck", "Head"]))
+	almost(HumanoidMap.coverage(full), 1.0, 1e-6, "全命中覆盖率 1.0")
+	ok(HumanoidMap.coverage(partial) < 1.0, "部分命中覆盖率小于 1")
+	ok(HumanoidMap.coverage(partial) > 0.0, "部分命中覆盖率大于 0")
+
+
+# ---------------- 真实模型 ----------------
+
+func test_real_vrm_loads_with_skeleton_and_bones() -> void:
+	var path := _find_model_path()
+	if path == "":
+		skip("真实 VRM 加载", "未找到模型文件（放置于 _scratch/sample.vrm 或传 --vrm=<路径>）")
+		return
+
+	var model: VrmLoader.VrmModel = VrmLoader.load_from_file(path)
+	not_null(model, "加载返回结果")
+
+	if not model.available:
+		ok(false, "模型加载失败", model.error)
+		return
+
+	is_true(model.available, "模型可用")
+	eq(model.error, "", "无错误信息")
+	not_null(model.root, "生成场景根节点")
+	not_null(model.skeleton, "找到 Skeleton3D")
+	ok(model.bone_count > 20, "骨骼数量合理", "实际 %d" % model.bone_count)
+	ok(model.mesh_count > 0, "含网格", "实际 %d" % model.mesh_count)
+	is_true(model.is_vrm, "识别为 VRM（含 VRM 扩展）")
+	ne(model.vrm_version, "", "读到 VRM 版本")
+	print("      → 模型：%s，VRM 版本 %s，%d 骨骼 / %d 网格，humanoid 覆盖率 %.0f%%" % [
+		path, model.vrm_version, model.bone_count, model.mesh_count, model.coverage() * 100.0,
+	])
+
+	ok(model.coverage() >= 0.8, "humanoid 骨骼覆盖率 ≥ 80%", "实际 %.0f%%，缺失：%s" % [
+		model.coverage() * 100.0, ", ".join(model.missing_bones()),
+	])
+	is_true(model.is_drivable(), "具备驱动所需的最小骨骼集合", "缺失：%s" % ", ".join(model.missing_bones()))
+
+	# 抽查若干关键骨骼确实指向名字匹配的骨骼
+	var checks := {
+		"hips": "Hips",
+		"leftHand": "Hand",
+		"rightUpperLeg": "UpperLeg",
+	}
+	for canonical in checks:
+		var index := model.bone_index(canonical)
+		ok(index >= 0, "%s 已映射" % canonical)
+		if index >= 0:
+			var bone_name := model.skeleton.get_bone_name(index)
+			contains(bone_name.to_lower(), str(checks[canonical]).to_lower(), "%s 映射到 %s" % [canonical, bone_name])
+			# 辅助骨不得被选用
+			is_false(bone_name.begins_with("J_Aim"), "%s 未误映射到 J_Aim 辅助骨（实际 %s）" % [canonical, bone_name])
+			is_false(bone_name.begins_with("J_Roll"), "%s 未误映射到 J_Roll 辅助骨（实际 %s）" % [canonical, bone_name])
+
+	model.dispose()
+	is_null(model.root, "dispose 后释放场景")
+
+
+func test_missing_file_reports_clear_error() -> void:
+	var model: VrmLoader.VrmModel = VrmLoader.load_from_file("res://_scratch/definitely-not-here.vrm")
+	is_false(model.available, "不存在的文件标记为不可用")
+	contains(model.error, "不存在", "错误信息说明文件不存在")
+
+
+func test_vrm_version_detection_from_json() -> void:
+	var v1 := VrmLoader.detect_vrm_version({"extensions": {"VRMC_vrm": {"specVersion": "1.0"}}})
+	is_true(bool(v1["is_vrm"]), "VRMC_vrm 识别为 VRM")
+	eq(str(v1["version"]), "1.0", "VRM 1.0 版本号正确")
+
+	var v0 := VrmLoader.detect_vrm_version({"extensions": {"VRM": {"specVersion": "0.0", "exporterVersion": "0.79"}}})
+	is_true(bool(v0["is_vrm"]), "VRM 识别为 VRM")
+	eq(str(v0["version"]), "0.0", "VRM 0.x 版本号正确")
+
+	var plain := VrmLoader.detect_vrm_version({"extensions": {}})
+	is_false(bool(plain["is_vrm"]), "无 VRM 扩展的普通 glTF 不识别为 VRM")
+	eq(str(plain["version"]), "", "普通 glTF 版本号为空")