diff --git a/internal/app/hostcaps_test.go b/internal/app/hostcaps_test.go
index ee94b3f..04ed066 100644
--- a/internal/app/hostcaps_test.go
+++ b/internal/app/hostcaps_test.go
@@ -26,11 +26,15 @@ func TestCapabilityExplainProviderExplainsBoundActorOnly(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	if _, err := st.ReplaceRolePermissions("admin", role.RoleID, role.RoleVersion, []store.RolePermissionChange{
-		{ActionID: "project.create", Allowed: true, CapAllowed: true},
-		{ActionID: "document.read", Allowed: true, CapAllowed: true},
-		{ActionID: "document.review", Allowed: false, CapAllowed: true},
-	}, "explain-provider"); err != nil {
+	// 收窄模型（R2）：职位角色只携带单一 project.create 行；document.* /
+	// project.* 等其他动作由系统授权或项目成员关系承担，写到角色行被
+	// ReplaceRolePermissions 拒绝（ErrInvalidRolePolicy）。fixture 只设
+	// project.create，断言围绕这条窄权限：CreateAuthority 投影到四个
+	// ProjectCreateLinkedActions、MemberBasicCollaborate 全 action-unconfigured、
+	// DocumentQualify 三职责都 action-unconfigured。
+	if _, err := st.ReplaceRolePermissions("admin", role.RoleID, role.RoleVersion,
+		[]store.RolePermissionChange{{ActionID: "project.create", Allowed: true, CapAllowed: true}},
+		"explain-provider"); err != nil {
 		t.Fatal(err)
 	}
 	if _, err := st.AssignUserRole("admin", alice.ID, role.RoleID, alice.StateVersion, "explain-provider-assign"); err != nil {
@@ -59,8 +63,11 @@ func TestCapabilityExplainProviderExplainsBoundActorOnly(t *testing.T) {
 	if err != nil || member.UserID != alice.ID || len(member.Actions) == 0 {
 		t.Fatalf("member=%+v err=%v", member, err)
 	}
+	// 角色权限投影：document.read 不在职位权限（只有 project.create），因此不能
+	// 被 Source=CapabilitySourceRole 标记为允许；来源必须是空、Reason 必须是
+	// "action-unconfigured"——这条边界保护正是窄模型的保护意图。
 	for _, action := range member.Actions {
-		if action.ActionID == "document.read" && (!action.Allowed || action.Source != extension.CapabilitySourceRole) {
+		if action.ActionID == "document.read" && (action.Allowed || action.Source == extension.CapabilitySourceRole || action.Reason != "action-unconfigured") {
 			t.Fatalf("document.read=%+v", action)
 		}
 	}
@@ -68,8 +75,13 @@ func TestCapabilityExplainProviderExplainsBoundActorOnly(t *testing.T) {
 	if err != nil || document.UserID != alice.ID || len(document.Duties) != 3 {
 		t.Fatalf("document=%+v err=%v", document, err)
 	}
+	// 三职责不被职位权限（project.create）直接资格化，因此 Qualified=false、
+	// DefaultAllowed=false、Source 空、Reason 为 action-unconfigured；这与
+	// 历史上「Allowed=false CapAllowed=true 单独写入」的职责资格语义不同——
+	// 那条路径已被 ReplaceRolePermissions 拒绝，本测试在不依赖该历史路径的
+	// 前提下保留职责资格投影的边界验证。
 	for _, duty := range document.Duties {
-		if duty.ActionID == "document.review" && (!duty.Qualified || duty.DefaultAllowed) {
+		if duty.ActionID == "document.review" && (duty.Qualified || duty.DefaultAllowed || duty.Source == extension.CapabilitySourceRole || duty.Reason != "action-unconfigured") {
 			t.Fatalf("document.review=%+v", duty)
 		}
 	}