fix(pinned): restore latest context usage

src/bot/pinned/pinned-message-manager.ts

@@ -174,9 +174,10 @@ class PinnedMessageManager {
         return;
       }
 
-      // Get the maximum context size and total cost from session history
+      // Get the latest measured context size and total cost from session history
       // Context = input + cache.read (cache.read contains previously cached context)
-      let maxContextSize = 0;
+      let latestContextSize = 0;
+      let latestContextCreated = Number.NEGATIVE_INFINITY;
       let totalCost = 0;
       logger.debug(`[PinnedManager] Processing ${messagesData.length} messages from history`);
 
@@ -188,6 +189,7 @@ class PinnedMessageManager {
               input: number;
               cache?: { read: number };
             };
+            time?: { created?: number };
             cost?: number;
           };
 
@@ -206,17 +208,18 @@ class PinnedMessageManager {
             `[PinnedManager] Assistant message: input=${input}, cache.read=${cacheRead}, total=${contextSize}, cost=$${cost.toFixed(2)}`,
           );
 
-          // Keep track of maximum context size (peak usage in session)
-          if (contextSize > maxContextSize) {
-            maxContextSize = contextSize;
+          const created = assistantInfo.time?.created ?? 0;
+          if (contextSize > 0 && created >= latestContextCreated) {
+            latestContextSize = contextSize;
+            latestContextCreated = created;
           }
 
           // Accumulate total session cost
           totalCost += cost;
         }
       });
 
-      this.state.tokensUsed = maxContextSize;
+      this.state.tokensUsed = latestContextSize;
       this.state.cost = totalCost;
       this.state.sessionId = sessionId;
 

tests/bot/pinned/pinned-message-manager.test.ts

@@ -2,7 +2,10 @@ import { beforeEach, describe, expect, it, vi } from "vitest";
 
 const mocked = vi.hoisted(() => ({
   opencodeClient: {
-    session: { list: vi.fn().mockResolvedValue({ data: [] }) },
+    session: {
+      list: vi.fn().mockResolvedValue({ data: [] }),
+      messages: vi.fn().mockResolvedValue({ data: [] }),
+    },
     config: { get: vi.fn().mockResolvedValue({ data: {} }) },
   },
   getCurrentSession: vi.fn(),
@@ -83,6 +86,7 @@ describe("pinned/manager", () => {
     mocked.getStoredModel.mockReturnValue({ providerID: "openai", modelID: "gpt-5" });
     mocked.getModelContextLimit.mockResolvedValue(204800);
     mocked.getPinnedMessageId.mockReturnValue(null);
+    mocked.opencodeClient.session.messages.mockResolvedValue({ data: [] });
     mocked.getGitWorktreeContext.mockResolvedValue({
       mainProjectPath: "D:/repo",
       activeWorktreePath: "D:/repo",
@@ -92,6 +96,59 @@ describe("pinned/manager", () => {
     });
   });
 
+  describe("loadContextFromHistory", () => {
+    it("restores the latest non-summary non-zero context instead of the historical peak", async () => {
+      await pinnedMessageManager.onSessionChange("ses-1", "Test Session");
+      mocked.opencodeClient.session.messages.mockResolvedValue({
+        data: [
+          {
+            info: {
+              role: "assistant",
+              time: { created: 200 },
+              tokens: { input: 300, cache: { read: 100 } },
+              cost: 0.5,
+            },
+            parts: [],
+          },
+          {
+            info: {
+              role: "assistant",
+              time: { created: 100 },
+              tokens: { input: 900, cache: { read: 100 } },
+              cost: 0.25,
+            },
+            parts: [],
+          },
+          {
+            info: {
+              role: "assistant",
+              time: { created: 300 },
+              tokens: { input: 0, cache: { read: 0 } },
+              cost: 0.1,
+            },
+            parts: [],
+          },
+          {
+            info: {
+              role: "assistant",
+              summary: true,
+              time: { created: 400 },
+              tokens: { input: 1500, cache: { read: 0 } },
+              cost: 4,
+            },
+            parts: [],
+          },
+        ],
+      });
+
+      await pinnedMessageManager.loadContextFromHistory("ses-1", "D:/repo");
+
+      const state = pinnedMessageManager.getState();
+      expect(state.tokensUsed).toBe(400);
+      expect(state.cost).toBeCloseTo(0.85);
+    });
+  });
+
   describe("updateTokensSilent", () => {
     it("updates tokensUsed in memory without triggering API call", () => {
       pinnedMessageManager.updateTokensSilent({