diff --git a/extensions/discord/src/internal/gateway.test.ts b/extensions/discord/src/internal/gateway.test.ts
index ba37791f6d8..206bafccfbb 100644
--- a/extensions/discord/src/internal/gateway.test.ts
+++ b/extensions/discord/src/internal/gateway.test.ts
@@ -484,15 +484,15 @@ describe("GatewayPlugin", () => {
     expect(gateway.ws).toBeNull();
     expect(gateway.firstHeartbeatTimeout).toBeUndefined();
     expect(gateway.heartbeatInterval).toBeUndefined();
-    expect(() => vi.advanceTimersByTime(20)).not.toThrow();
+    vi.advanceTimersByTime(20);
     expect(send).not.toHaveBeenCalled();
-    expect(() =>
+    expect(
       (
         gateway as unknown as {
           sendHeartbeat(): void;
         }
       ).sendHeartbeat(),
-    ).not.toThrow();
+    ).toBeUndefined();
   });
 
   it("clears stale heartbeat timers before early reconnect exits", () => {
diff --git a/extensions/discord/src/monitor/provider.test.ts b/extensions/discord/src/monitor/provider.test.ts
index de5b6479562..c6390da5ccc 100644
--- a/extensions/discord/src/monitor/provider.test.ts
+++ b/extensions/discord/src/monitor/provider.test.ts
@@ -327,9 +327,9 @@ describe("monitorDiscordProvider", () => {
 
     expect(monitorLifecycleMock).not.toHaveBeenCalled();
     expect(disconnect).toHaveBeenCalledTimes(1);
-    expect(() =>
+    expect(
       emitter.emit("error", new Error("Max reconnect attempts (0) reached after code 1005")),
-    ).not.toThrow();
+    ).toBe(true);
     expect(runtime.error).toHaveBeenCalledWith(
       expect.stringContaining("suppressed late gateway reconnect-exhausted error after dispose"),
     );
diff --git a/extensions/discord/src/voice/manager.e2e.test.ts b/extensions/discord/src/voice/manager.e2e.test.ts
index 59d178e238b..9e074017c70 100644
--- a/extensions/discord/src/voice/manager.e2e.test.ts
+++ b/extensions/discord/src/voice/manager.e2e.test.ts
@@ -412,7 +412,7 @@ describe("DiscordVoiceManager", () => {
     expectConnectedStatus(manager, "1002");
   });
 
-  it("does not throw when stale tracked voice connections are already destroyed", async () => {
+  it("skips destroying stale tracked voice connections that are already destroyed", async () => {
     const staleConnection = createConnectionMock();
     staleConnection.state.status = "destroyed";
     staleConnection.destroy.mockImplementation(() => {
@@ -429,7 +429,7 @@ describe("DiscordVoiceManager", () => {
     expect(staleConnection.destroy).not.toHaveBeenCalled();
   });
 
-  it("does not throw when leaving an already destroyed voice connection", async () => {
+  it("skips destroying an already destroyed voice connection on leave", async () => {
     const connection = createConnectionMock();
     connection.destroy.mockImplementation(() => {
       throw new Error("Cannot destroy VoiceConnection - it has already been destroyed");
@@ -1095,7 +1095,7 @@ describe("DiscordVoiceManager", () => {
     expect(agentCommandMock).toHaveBeenCalledTimes(1);
   });
 
-  it("DiscordVoiceReadyListener: propagates autoJoin errors fire-and-forget without throwing", async () => {
+  it("DiscordVoiceReadyListener: starts autoJoin fire-and-forget on ready", async () => {
     const manager = createManager();
     const autoJoinSpy = vi
       .spyOn(manager, "autoJoin")
@@ -1104,7 +1104,7 @@ describe("DiscordVoiceManager", () => {
     const { DiscordVoiceReadyListener } = managerModule;
     const listener = new DiscordVoiceReadyListener(manager);
 
-    await expect(listener.handle(undefined, undefined as never)).resolves.not.toThrow();
+    await expect(listener.handle(undefined, undefined as never)).resolves.toBeUndefined();
     expect(autoJoinSpy).toHaveBeenCalledTimes(1);
   });
 
@@ -1115,7 +1115,7 @@ describe("DiscordVoiceManager", () => {
     const { DiscordVoiceResumedListener } = managerModule;
     const listener = new DiscordVoiceResumedListener(manager);
 
-    await expect(listener.handle(undefined, undefined as never)).resolves.not.toThrow();
+    await expect(listener.handle(undefined, undefined as never)).resolves.toBeUndefined();
     expect(autoJoinSpy).toHaveBeenCalledTimes(1);
   });
 });
diff --git a/extensions/matrix/src/matrix/monitor/mentions.test.ts b/extensions/matrix/src/matrix/monitor/mentions.test.ts
index 14aae68654e..3c18a690858 100644
--- a/extensions/matrix/src/matrix/monitor/mentions.test.ts
+++ b/extensions/matrix/src/matrix/monitor/mentions.test.ts
@@ -228,7 +228,7 @@ describe("resolveMentions", () => {
     });
 
     it("ignores out-of-range hexadecimal HTML entities in visible labels", () => {
-      expect(() =>
+      expect(
         resolveMentions({
           content: {
             msgtype: "m.text",
@@ -239,11 +239,11 @@ describe("resolveMentions", () => {
           text: "hello",
           mentionRegexes: [],
         }),
-      ).not.toThrow();
+      ).toEqual({ hasExplicitMention: false, wasMentioned: false });
     });
 
     it("ignores oversized decimal HTML entities in visible labels", () => {
-      expect(() =>
+      expect(
         resolveMentions({
           content: {
             msgtype: "m.text",
@@ -255,7 +255,7 @@ describe("resolveMentions", () => {
           text: "hello",
           mentionRegexes: [],
         }),
-      ).not.toThrow();
+      ).toEqual({ hasExplicitMention: false, wasMentioned: false });
     });
 
     it("does not detect mention when displayName is spoofed", () => {
diff --git a/extensions/matrix/src/matrix/sdk.test.ts b/extensions/matrix/src/matrix/sdk.test.ts
index 693e638e2ad..8026f7ffc82 100644
--- a/extensions/matrix/src/matrix/sdk.test.ts
+++ b/extensions/matrix/src/matrix/sdk.test.ts
@@ -1573,8 +1573,7 @@ describe("MatrixClient crypto bootstrapping", () => {
       }
     ).cryptoBootstrapper.bootstrap = bootstrapSpy;
 
-    // start() must NOT throw even when the repair bootstrap fails
-    await expect(client.start()).resolves.not.toThrow();
+    await expect(client.start()).resolves.toBeUndefined();
 
     // repair was attempted
     expect(bootstrapSpy).toHaveBeenCalledTimes(2);