diff --git a/src/gateway/managed-image-attachments.test.ts b/src/gateway/managed-image-attachments.test.ts
index c5967b6fa21..1f2f83071e9 100644
--- a/src/gateway/managed-image-attachments.test.ts
+++ b/src/gateway/managed-image-attachments.test.ts
@@ -73,7 +73,7 @@ async function createNoisyPngBuffer(width: number, height: number): Promise<Buff
 }
 
 function requireAttachmentIdFromUrl(url: unknown): string {
-  expect(url).toEqual(expect.any(String));
+  expect(url).toBeTypeOf("string");
   const attachmentId = String(url).split("/").at(-2);
   if (!attachmentId) {
     throw new Error(`expected attachment id in URL ${String(url)}`);
diff --git a/src/gateway/server.talk-config.test.ts b/src/gateway/server.talk-config.test.ts
index efcc08c8a40..f85342f74c7 100644
--- a/src/gateway/server.talk-config.test.ts
+++ b/src/gateway/server.talk-config.test.ts
@@ -85,7 +85,7 @@ async function createFreshOperatorDevice(scopes: string[], nonce: string) {
 
 async function connectOperator(ws: GatewaySocket, scopes: string[]) {
   const nonce = await readConnectChallengeNonce(ws);
-  expect(nonce).toEqual(expect.any(String));
+  expect(nonce).toBeTypeOf("string");
   expect(String(nonce).length).toBeGreaterThan(0);
   await connectOk(ws, {
     token: "secret",
diff --git a/src/logging/logger-redaction-behavior.test.ts b/src/logging/logger-redaction-behavior.test.ts
index 274bb3a63ea..8acaa74d7d3 100644
--- a/src/logging/logger-redaction-behavior.test.ts
+++ b/src/logging/logger-redaction-behavior.test.ts
@@ -149,7 +149,7 @@ describe("file log redaction", () => {
 
     const [line] = fs.readFileSync(logPath, "utf8").trim().split("\n");
     const record = JSON.parse(line ?? "{}") as Record<string, unknown>;
-    expect(record.hostname).toEqual(expect.any(String));
+    expect(record.hostname).toBeTypeOf("string");
     expect(record.hostname).not.toBe("");
     expect(record.message).toBe("request completed");
   });