diff --git a/docs/feat/admin-panel-dashboard-feat.md b/docs/feat/admin-panel-dashboard-feat.md
index 1afd8d2..ae9951d 100644
--- a/docs/feat/admin-panel-dashboard-feat.md
+++ b/docs/feat/admin-panel-dashboard-feat.md
@@ -1,4 +1,4 @@
-# EZ-API 控制平面仪表盘 (Dashboard) 前后端对接功能文档
+# EZ-API admin-panel Dashboard 功能文档
 
 ## 1. 文档概述
 
@@ -253,9 +253,8 @@
 |--------|------|
 | Mock 数据 | 前端可利用 Mock 数据先行开发 UI |
 | Swagger 验证 | 复杂聚合接口建议先在 Swagger 中验证 |
-| 自动化测试 | 利用 Mock Server 进行前端组件测试 |
 | 性能监控 | 关注 traffic-chart 接口在大数据量下的响应时间 |
 
 ---
 
-*注：本对接文档基于现有端点整理，Billing 模块后端尚未实现。*
+*注：本对接文档基于现有端点整理*
diff --git a/internal/api/dashboard_handler.go b/internal/api/dashboard_handler.go
index 3284afc..da8ac6e 100644
--- a/internal/api/dashboard_handler.go
+++ b/internal/api/dashboard_handler.go
@@ -89,6 +89,31 @@ func CalculateTrendFloat(current, previous float64) TrendInfo {
 	return TrendInfo{Delta: &delta, Direction: direction}
 }
 
+// CalculateTrendFloatWithBaseline calculates trend when baseline existence is explicit.
+func CalculateTrendFloatWithBaseline(current, previous float64, hasBaseline bool) TrendInfo {
+	if !hasBaseline {
+		if current == 0 {
+			return TrendInfo{Direction: "stable"}
+		}
+		return TrendInfo{Direction: "new"}
+	}
+	if previous == 0 {
+		if current == 0 {
+			return TrendInfo{Direction: "stable"}
+		}
+		return TrendInfo{Direction: "up"}
+	}
+	delta := (current - previous) / previous * 100
+	delta = math.Round(delta*10) / 10
+	direction := "stable"
+	if delta > 0.5 {
+		direction = "up"
+	} else if delta < -0.5 {
+		direction = "down"
+	}
+	return TrendInfo{Delta: &delta, Direction: direction}
+}
+
 // RequestStats contains request-related statistics
 type RequestStats struct {
 	Total     int64   `json:"total"`
@@ -302,20 +327,21 @@ func (h *DashboardHandler) GetSummary(c *gin.Context) {
 		if !prevStart.IsZero() && !prevEnd.IsZero() {
 			prevStats, err := h.aggregateFromLogRecords(prevStart, prevEnd)
 			if err == nil {
+				hasBaseline := prevStats.Requests > 0
 				prevErrorRate := 0.0
-				if prevStats.Requests > 0 {
+				if hasBaseline {
 					prevErrorRate = float64(prevStats.Failed) / float64(prevStats.Requests)
 				}
 				prevAvgLatency := 0.0
-				if prevStats.Requests > 0 {
+				if hasBaseline {
 					prevAvgLatency = float64(prevStats.LatencySumMs) / float64(prevStats.Requests)
 				}
 
 				trends = &DashboardTrends{
 					Requests:  CalculateTrend(totalRequests, prevStats.Requests),
 					Tokens:    CalculateTrend(ts.TokensIn+ts.TokensOut, prevStats.TokensIn+prevStats.TokensOut),
-					ErrorRate: CalculateTrendFloat(errorRate, prevErrorRate),
-					Latency:   CalculateTrendFloat(ts.AvgLatency, prevAvgLatency),
+					ErrorRate: CalculateTrendFloatWithBaseline(errorRate, prevErrorRate, hasBaseline),
+					Latency:   CalculateTrendFloatWithBaseline(ts.AvgLatency, prevAvgLatency, hasBaseline),
 				}
 			}
 		}
diff --git a/internal/api/dashboard_handler_test.go b/internal/api/dashboard_handler_test.go
index ee8dd93..52baf12 100644
--- a/internal/api/dashboard_handler_test.go
+++ b/internal/api/dashboard_handler_test.go
@@ -162,6 +162,88 @@ func TestCalculateTrendFloat(t *testing.T) {
 	}
 }
 
+func TestCalculateTrendFloatWithBaseline(t *testing.T) {
+	tests := []struct {
+		name          string
+		current       float64
+		previous      float64
+		hasBaseline   bool
+		wantDelta     *float64
+		wantDirection string
+	}{
+		{
+			name:          "no baseline, zero current",
+			current:       0,
+			previous:      0,
+			hasBaseline:   false,
+			wantDelta:     nil,
+			wantDirection: "stable",
+		},
+		{
+			name:          "no baseline, positive current",
+			current:       0.2,
+			previous:      0,
+			hasBaseline:   false,
+			wantDelta:     nil,
+			wantDirection: "new",
+		},
+		{
+			name:          "baseline present, zero previous and current",
+			current:       0,
+			previous:      0,
+			hasBaseline:   true,
+			wantDelta:     nil,
+			wantDirection: "stable",
+		},
+		{
+			name:          "baseline present, zero previous to positive",
+			current:       0.2,
+			previous:      0,
+			hasBaseline:   true,
+			wantDelta:     nil,
+			wantDirection: "up",
+		},
+		{
+			name:          "baseline present, increase",
+			current:       0.15,
+			previous:      0.10,
+			hasBaseline:   true,
+			wantDelta:     ptr(50.0),
+			wantDirection: "up",
+		},
+		{
+			name:          "baseline present, no change",
+			current:       0.10,
+			previous:      0.10,
+			hasBaseline:   true,
+			wantDelta:     ptr(0.0),
+			wantDirection: "stable",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := CalculateTrendFloatWithBaseline(tt.current, tt.previous, tt.hasBaseline)
+
+			if tt.wantDelta == nil {
+				if got.Delta != nil {
+					t.Errorf("expected nil delta, got %v", *got.Delta)
+				}
+			} else {
+				if got.Delta == nil {
+					t.Errorf("expected delta %v, got nil", *tt.wantDelta)
+				} else if *got.Delta != *tt.wantDelta {
+					t.Errorf("expected delta %v, got %v", *tt.wantDelta, *got.Delta)
+				}
+			}
+
+			if got.Direction != tt.wantDirection {
+				t.Errorf("expected direction %q, got %q", tt.wantDirection, got.Direction)
+			}
+		})
+	}
+}
+
 func TestPreviousPeriodWindow(t *testing.T) {
 	// These tests verify the structure of the period calculation
 	// Not testing exact timestamps since they depend on current time