diff --git a/src/services/file-service.ts b/src/services/file-service.ts
index b246cb9a..0ffc42da 100644
--- a/src/services/file-service.ts
+++ b/src/services/file-service.ts
@@ -5,7 +5,7 @@
  * Features:
  * - File upload via GraphQL fileUpload mutation
  * - File download with automatic authentication
- * - Signed URL detection (skips Bearer token for signed URLs)
+ * - Signed URL detection (skips authentication for signed URLs)
  * - Directory creation and file existence checks
  * - Comprehensive error handling and status reporting
  */
@@ -139,7 +139,7 @@ export class FileService {
    * Downloads a file from Linear's private cloud storage.
    *
    * Automatically handles authentication for Linear URLs and creates directories
-   * as needed. Detects signed URLs to skip Bearer token authentication.
+   * as needed. Detects signed URLs to skip authentication.
    *
    * @param url - URL to Linear file (uploads.linear.app domain)
    * @param options - Download options including output path and overwrite behavior
@@ -192,10 +192,9 @@ export class FileService {
       const urlObj = new URL(url);
       const isSignedUrl = urlObj.searchParams.has("signature");
 
-      // Make HTTP request (with Bearer token only if not a signed URL)
       const headers: Record<string, string> = {};
       if (!isSignedUrl) {
-        headers["Authorization"] = `Bearer ${this.apiToken}`;
+        headers["Authorization"] = this.apiToken;
       }
 
       const response = await fetch(url, {
diff --git a/tests/unit/services/file-service.test.ts b/tests/unit/services/file-service.test.ts
index 52916ec4..ec348154 100644
--- a/tests/unit/services/file-service.test.ts
+++ b/tests/unit/services/file-service.test.ts
@@ -26,7 +26,7 @@ import {
 const mockFetch = vi.fn();
 vi.stubGlobal("fetch", mockFetch);
 
-const TEST_TOKEN = "lin_api_test_token";
+const TEST_TOKEN = "test_token";
 
 beforeEach(() => {
   vi.clearAllMocks();
@@ -50,7 +50,10 @@ describe("downloadFile", () => {
     expect(mockFetch).not.toHaveBeenCalled();
   });
 
-  it("downloads file successfully", async () => {
+  it.each([
+    ["a personal API key", "", { Authorization: TEST_TOKEN }],
+    ["no credentials on a signed URL", "?signature=test", {}],
+  ])("downloads with %s", async (_name, query, expectedHeaders) => {
     vi.mocked(isLinearUploadUrl).mockReturnValue(true);
     vi.mocked(extractFilenameFromUrl).mockReturnValue("image.png");
     vi.mocked(access).mockRejectedValue(new Error("ENOENT")); // file doesn't exist
@@ -65,19 +68,18 @@ describe("downloadFile", () => {
     });
 
     const service = new FileService(TEST_TOKEN);
-    const result = await service.downloadFile(
-      "https://uploads.linear.app/org/file.png",
-    );
+    const url = `https://uploads.linear.app/org/file.png${query}`;
+    const result = await service.downloadFile(url);
 
     expect(result).toEqual({
       success: true,
       filePath: "image.png",
     });
     expect(mockFetch).toHaveBeenCalledWith(
-      "https://uploads.linear.app/org/file.png",
+      url,
       expect.objectContaining({
         method: "GET",
-        headers: { Authorization: `Bearer ${TEST_TOKEN}` },
+        headers: expectedHeaders,
       }),
     );
     expect(writeFile).toHaveBeenCalled();