diff --git a/src/telegram/bot-message-context.dm-topic-threadid.test.ts b/src/telegram/bot-message-context.dm-topic-threadid.test.ts
index ffef2f592cb..f83d66082ea 100644
--- a/src/telegram/bot-message-context.dm-topic-threadid.test.ts
+++ b/src/telegram/bot-message-context.dm-topic-threadid.test.ts
@@ -14,26 +14,25 @@ describe("buildTelegramMessageContext DM topic threadId in deliveryContext (#889
     messages: { groupChat: { mentionPatterns: [] } },
   } as never;
 
-  beforeEach(() => {
-    recordInboundSessionMock.mockClear();
-  });
-
-  it("passes threadId to updateLastRoute for DM topics", async () => {
-    const ctx = await buildTelegramMessageContext({
+  async function buildCtx(params: {
+    message: Record<string, unknown>;
+    options?: Record<string, unknown>;
+    resolveGroupActivation?: () => unknown;
+  }): Promise<Awaited<ReturnType<typeof buildTelegramMessageContext>>> {
+    return await buildTelegramMessageContext({
       primaryCtx: {
         message: {
           message_id: 1,
-          chat: { id: 1234, type: "private" },
           date: 1700000000,
           text: "hello",
-          message_thread_id: 42, // DM Topic ID
           from: { id: 42, first_name: "Alice" },
+          ...params.message,
         },
         me: { id: 7, username: "bot" },
       } as never,
       allMedia: [],
       storeAllowFrom: [],
-      options: {},
+      options: params.options ?? {},
       bot: {
         api: {
           sendChatAction: vi.fn(),
@@ -49,121 +48,72 @@ describe("buildTelegramMessageContext DM topic threadId in deliveryContext (#889
       groupAllowFrom: [],
       ackReactionScope: "off",
       logger: { info: vi.fn() },
-      resolveGroupActivation: () => undefined,
+      resolveGroupActivation: params.resolveGroupActivation ?? (() => undefined),
       resolveGroupRequireMention: () => false,
       resolveTelegramGroupConfig: () => ({
         groupConfig: { requireMention: false },
         topicConfig: undefined,
       }),
     });
+  }
+
+  function getUpdateLastRoute(): unknown {
+    const callArgs = recordInboundSessionMock.mock.calls[0]?.[0] as { updateLastRoute?: unknown };
+    return callArgs?.updateLastRoute;
+  }
+
+  beforeEach(() => {
+    recordInboundSessionMock.mockClear();
+  });
+
+  it("passes threadId to updateLastRoute for DM topics", async () => {
+    const ctx = await buildCtx({
+      message: {
+        chat: { id: 1234, type: "private" },
+        message_thread_id: 42, // DM Topic ID
+      },
+    });
 
     expect(ctx).not.toBeNull();
     expect(recordInboundSessionMock).toHaveBeenCalled();
 
     // Check that updateLastRoute includes threadId
-    const callArgs = recordInboundSessionMock.mock.calls[0]?.[0] as {
-      updateLastRoute?: { threadId?: string };
-    };
-    expect(callArgs?.updateLastRoute).toBeDefined();
-    expect(callArgs?.updateLastRoute?.threadId).toBe("42");
+    const updateLastRoute = getUpdateLastRoute() as { threadId?: string } | undefined;
+    expect(updateLastRoute).toBeDefined();
+    expect(updateLastRoute?.threadId).toBe("42");
   });
 
   it("does not pass threadId for regular DM without topic", async () => {
-    const ctx = await buildTelegramMessageContext({
-      primaryCtx: {
-        message: {
-          message_id: 1,
-          chat: { id: 1234, type: "private" },
-          date: 1700000000,
-          text: "hello",
-          // No message_thread_id
-          from: { id: 42, first_name: "Alice" },
-        },
-        me: { id: 7, username: "bot" },
-      } as never,
-      allMedia: [],
-      storeAllowFrom: [],
-      options: {},
-      bot: {
-        api: {
-          sendChatAction: vi.fn(),
-          setMessageReaction: vi.fn(),
-        },
-      } as never,
-      cfg: baseConfig,
-      account: { accountId: "default" } as never,
-      historyLimit: 0,
-      groupHistories: new Map(),
-      dmPolicy: "open",
-      allowFrom: [],
-      groupAllowFrom: [],
-      ackReactionScope: "off",
-      logger: { info: vi.fn() },
-      resolveGroupActivation: () => undefined,
-      resolveGroupRequireMention: () => false,
-      resolveTelegramGroupConfig: () => ({
-        groupConfig: { requireMention: false },
-        topicConfig: undefined,
-      }),
+    const ctx = await buildCtx({
+      message: {
+        chat: { id: 1234, type: "private" },
+      },
     });
 
     expect(ctx).not.toBeNull();
     expect(recordInboundSessionMock).toHaveBeenCalled();
 
     // Check that updateLastRoute does NOT include threadId
-    const callArgs = recordInboundSessionMock.mock.calls[0]?.[0] as {
-      updateLastRoute?: { threadId?: string };
-    };
-    expect(callArgs?.updateLastRoute).toBeDefined();
-    expect(callArgs?.updateLastRoute?.threadId).toBeUndefined();
+    const updateLastRoute = getUpdateLastRoute() as { threadId?: string } | undefined;
+    expect(updateLastRoute).toBeDefined();
+    expect(updateLastRoute?.threadId).toBeUndefined();
   });
 
   it("does not set updateLastRoute for group messages", async () => {
-    const ctx = await buildTelegramMessageContext({
-      primaryCtx: {
-        message: {
-          message_id: 1,
-          chat: { id: -1001234567890, type: "supergroup", title: "Test Group" },
-          date: 1700000000,
-          text: "@bot hello",
-          message_thread_id: 99,
-          from: { id: 42, first_name: "Alice" },
-        },
-        me: { id: 7, username: "bot" },
-      } as never,
-      allMedia: [],
-      storeAllowFrom: [],
+    const ctx = await buildCtx({
+      message: {
+        chat: { id: -1001234567890, type: "supergroup", title: "Test Group" },
+        text: "@bot hello",
+        message_thread_id: 99,
+      },
       options: { forceWasMentioned: true },
-      bot: {
-        api: {
-          sendChatAction: vi.fn(),
-          setMessageReaction: vi.fn(),
-        },
-      } as never,
-      cfg: baseConfig,
-      account: { accountId: "default" } as never,
-      historyLimit: 0,
-      groupHistories: new Map(),
-      dmPolicy: "open",
-      allowFrom: [],
-      groupAllowFrom: [],
-      ackReactionScope: "off",
-      logger: { info: vi.fn() },
       resolveGroupActivation: () => true,
-      resolveGroupRequireMention: () => false,
-      resolveTelegramGroupConfig: () => ({
-        groupConfig: { requireMention: false },
-        topicConfig: undefined,
-      }),
     });
 
     expect(ctx).not.toBeNull();
     expect(recordInboundSessionMock).toHaveBeenCalled();
 
     // Check that updateLastRoute is undefined for groups
-    const callArgs = recordInboundSessionMock.mock.calls[0]?.[0] as {
-      updateLastRoute?: unknown;
-    };
-    expect(callArgs?.updateLastRoute).toBeUndefined();
+    expect(getUpdateLastRoute()).toBeUndefined();
   });
 });