diff --git a/apps/vis/server/src/lib/context-projector.ts b/apps/vis/server/src/lib/context-projector.ts
index 81569f9e3..57372bc96 100644
--- a/apps/vis/server/src/lib/context-projector.ts
+++ b/apps/vis/server/src/lib/context-projector.ts
@@ -170,8 +170,14 @@ export function projectContext(entries: ReadonlyArray<WireEntry>): ContextProjec
         }];
         break;
       case 'usage.record': {
-        const scope = (rec.usageScope ?? 'session') as 'session' | 'turn';
-        addUsage(usage.byScope[scope], rec.usage);
+        // `byScope.session` is the cumulative session total — every usage
+        // record, matching agent-core's UsageRecorder.total / byModel — while
+        // `byScope.turn` is the turn-scoped subset. The main agent loop records
+        // every step as 'turn', so partitioning records into one bucket OR the
+        // other left `byScope.session` near-empty and under-reported the Context
+        // tab token bar, which reads `byScope.session`.
+        addUsage(usage.byScope.session, rec.usage);
+        if ((rec.usageScope ?? 'session') === 'turn') addUsage(usage.byScope.turn, rec.usage);
         if (!usage.byModel[rec.model]) usage.byModel[rec.model] = { ...ZERO };
         addUsage(usage.byModel[rec.model]!, rec.usage);
         break;
diff --git a/apps/vis/server/test/lib/context-projector.test.ts b/apps/vis/server/test/lib/context-projector.test.ts
index 1d63f1d85..014dd7d75 100644
--- a/apps/vis/server/test/lib/context-projector.test.ts
+++ b/apps/vis/server/test/lib/context-projector.test.ts
@@ -25,6 +25,13 @@ describe('context-projector', () => {
     expect(proj.usage.byScope.turn).toEqual({
       inputOther: 10, output: 5, inputCacheRead: 0, inputCacheCreation: 0,
     });
+    // `byScope.session` is the cumulative session total — the sum of every
+    // usage record (matching `byModel`), not just records explicitly scoped
+    // 'session'. The main loop records every step as 'turn', so before the fix
+    // this bucket stayed {0,0,0,0} and the Context tab token bar read empty.
+    expect(proj.usage.byScope.session).toEqual({
+      inputOther: 10, output: 5, inputCacheRead: 0, inputCacheCreation: 0,
+    });
     expect(proj.usage.byModel['kimi-k2']).toEqual({
       inputOther: 10, output: 5, inputCacheRead: 0, inputCacheCreation: 0,
     });