fix: address analytics review follow-ups

src/web-server/usage/aggregator.ts

@@ -99,6 +99,10 @@ async function loadInstanceData(instancePath: string): Promise<{
   }
 }
 
+function getHourlyRequestCount(hour: HourlyUsage): number {
+  return hour.requestCount ?? hour.modelBreakdowns.length;
+}
+
 /**
  * Merge daily usage data from multiple sources
  * Combines entries with same date by aggregating tokens
@@ -208,7 +212,7 @@ export function mergeHourlyData(sources: HourlyUsage[][]): HourlyUsage[] {
         existing.cacheCreationTokens += hour.cacheCreationTokens;
         existing.cacheReadTokens += hour.cacheReadTokens;
         existing.totalCost += hour.totalCost;
-        existing.requestCount = (existing.requestCount ?? 0) + (hour.requestCount ?? 0);
+        existing.requestCount = getHourlyRequestCount(existing) + getHourlyRequestCount(hour);
         const modelSet = new Set([...existing.modelsUsed, ...hour.modelsUsed]);
         existing.modelsUsed = Array.from(modelSet);
         // Merge model breakdowns
@@ -231,7 +235,7 @@ export function mergeHourlyData(sources: HourlyUsage[][]): HourlyUsage[] {
           ...hour,
           modelsUsed: [...hour.modelsUsed],
           modelBreakdowns: hour.modelBreakdowns.map((b) => ({ ...b })),
-          requestCount: hour.requestCount ?? 0,
+          requestCount: getHourlyRequestCount(hour),
         });
       }
     }

src/web-server/usage/handlers.ts

@@ -694,6 +694,7 @@ export async function handleMonthly(
       cacheReadTokens: number;
       totalCost: number;
       modelsUsed: string[];
+      modelBreakdowns: DailyUsage['modelBreakdowns'];
     }>;
 
     if (since || until) {
@@ -708,6 +709,17 @@ export async function handleMonthly(
           cacheReadTokens: number;
           totalCost: number;
           modelsUsed: Set<string>;
+          modelBreakdowns: Map<
+            string,
+            {
+              modelName: string;
+              inputTokens: number;
+              outputTokens: number;
+              cacheCreationTokens: number;
+              cacheReadTokens: number;
+              cost: number;
+            }
+          >;
         }
       >();
 
@@ -721,6 +733,7 @@ export async function handleMonthly(
           cacheReadTokens: 0,
           totalCost: 0,
           modelsUsed: new Set<string>(),
+          modelBreakdowns: new Map(),
         };
 
         existing.inputTokens += day.inputTokens;
@@ -731,6 +744,22 @@ export async function handleMonthly(
         for (const model of day.modelsUsed) {
           existing.modelsUsed.add(model);
         }
+        for (const breakdown of day.modelBreakdowns) {
+          const existingBreakdown = existing.modelBreakdowns.get(breakdown.modelName) ?? {
+            modelName: breakdown.modelName,
+            inputTokens: 0,
+            outputTokens: 0,
+            cacheCreationTokens: 0,
+            cacheReadTokens: 0,
+            cost: 0,
+          };
+          existingBreakdown.inputTokens += breakdown.inputTokens;
+          existingBreakdown.outputTokens += breakdown.outputTokens;
+          existingBreakdown.cacheCreationTokens += breakdown.cacheCreationTokens;
+          existingBreakdown.cacheReadTokens += breakdown.cacheReadTokens;
+          existingBreakdown.cost += breakdown.cost;
+          existing.modelBreakdowns.set(breakdown.modelName, existingBreakdown);
+        }
 
         monthMap.set(month, existing);
       }
@@ -744,6 +773,7 @@ export async function handleMonthly(
           cacheReadTokens: month.cacheReadTokens,
           totalCost: month.totalCost,
           modelsUsed: Array.from(month.modelsUsed),
+          modelBreakdowns: Array.from(month.modelBreakdowns.values()),
         }))
         .sort((a, b) => a.month.localeCompare(b.month));
     } else {

tests/unit/web-server/usage-aggregator-cliproxy-integration.test.ts

@@ -306,4 +306,58 @@ describe('usage aggregator cliproxy integration', () => {
     expect(result[0].totalCost).toBe(3);
     expect(result[0].modelBreakdowns).toHaveLength(2);
   });
+
+  it('falls back to model cardinality when merging legacy hourly buckets without requestCount', () => {
+    const result = aggregator.mergeHourlyData([
+      [
+        {
+          hour: '2026-03-02 10:00',
+          source: 'legacy-a',
+          inputTokens: 10,
+          outputTokens: 1,
+          cacheCreationTokens: 0,
+          cacheReadTokens: 0,
+          cost: 1,
+          totalCost: 1,
+          modelsUsed: ['claude-sonnet-4-5'],
+          modelBreakdowns: [
+            {
+              modelName: 'claude-sonnet-4-5',
+              inputTokens: 10,
+              outputTokens: 1,
+              cacheCreationTokens: 0,
+              cacheReadTokens: 0,
+              cost: 1,
+            },
+          ],
+        },
+      ],
+      [
+        {
+          hour: '2026-03-02 10:00',
+          source: 'legacy-b',
+          inputTokens: 20,
+          outputTokens: 2,
+          cacheCreationTokens: 0,
+          cacheReadTokens: 0,
+          cost: 2,
+          totalCost: 2,
+          modelsUsed: ['gemini-2.5-pro'],
+          modelBreakdowns: [
+            {
+              modelName: 'gemini-2.5-pro',
+              inputTokens: 20,
+              outputTokens: 2,
+              cacheCreationTokens: 0,
+              cacheReadTokens: 0,
+              cost: 2,
+            },
+          ],
+        },
+      ],
+    ]);
+
+    expect(result).toHaveLength(1);
+    expect(result[0].requestCount).toBe(2);
+  });
 });