diff --git a/src/app/api/generate/__tests__/route.test.ts b/src/app/api/generate/__tests__/route.test.ts
index 318388b2..9311f6fa 100644
--- a/src/app/api/generate/__tests__/route.test.ts
+++ b/src/app/api/generate/__tests__/route.test.ts
@@ -2637,5 +2637,165 @@ describe("/api/generate route", () => {
       expect(data.success).toBe(false);
       expect(data.error).toContain("No media URL in response");
     });
+
+    it("should handle model_glb.url response format (Hunyuan 3D)", async () => {
+      // Schema fetch
+      mockFetch.mockResolvedValueOnce({
+        ok: true,
+        json: () => Promise.resolve({ models: [] }),
+      });
+
+      // Queue flow: submit → poll → result (model_glb format) → media fetch
+      // Queue submit
+      mockFetch.mockResolvedValueOnce({
+        ok: true,
+        json: () => Promise.resolve({ request_id: "test-req-id" }),
+      });
+      // Status poll → COMPLETED
+      mockFetch.mockResolvedValueOnce({
+        ok: true,
+        json: () => Promise.resolve({ status: "COMPLETED" }),
+      });
+      // Result fetch
+      mockFetch.mockResolvedValueOnce({
+        ok: true,
+        json: () => Promise.resolve({ model_glb: { url: "https://fal.media/hunyuan3d-output.glb" } }),
+      });
+      // Media fetch (needed to reach is3DModel check)
+      mockFetch.mockResolvedValueOnce({
+        ok: true,
+        headers: new Headers({ "content-type": "model/gltf-binary" }),
+        arrayBuffer: () => Promise.resolve(new ArrayBuffer(4096)),
+      });
+
+      const request = createMockPostRequest(
+        {
+          prompt: "A 3D model of a chair",
+          mediaType: "3d",
+          selectedModel: {
+            provider: "fal",
+            modelId: "fal-ai/hunyuan3d/mini",
+            displayName: "Hunyuan 3D Mini",
+          },
+        },
+        { "X-Fal-API-Key": "test-fal-key" }
+      );
+
+      const response = await POST(request);
+      const data = await response.json();
+
+      expect(response.status).toBe(200);
+      expect(data.success).toBe(true);
+      expect(data.contentType).toBe("3d");
+      expect(data.model3dUrl).toBe("https://fal.media/hunyuan3d-output.glb");
+    });
+
+    it("should handle model_urls.glb.url response format (Hunyuan 3D variant)", async () => {
+      // Schema fetch
+      mockFetch.mockResolvedValueOnce({
+        ok: true,
+        json: () => Promise.resolve({ models: [] }),
+      });
+
+      // Queue flow: submit → poll → result (model_urls.glb format) → media fetch
+      // Queue submit
+      mockFetch.mockResolvedValueOnce({
+        ok: true,
+        json: () => Promise.resolve({ request_id: "test-req-id" }),
+      });
+      // Status poll → COMPLETED
+      mockFetch.mockResolvedValueOnce({
+        ok: true,
+        json: () => Promise.resolve({ status: "COMPLETED" }),
+      });
+      // Result fetch
+      mockFetch.mockResolvedValueOnce({
+        ok: true,
+        json: () => Promise.resolve({ model_urls: { glb: { url: "https://fal.media/hunyuan3d-v2-output.glb" } } }),
+      });
+      // Media fetch (needed to reach is3DModel check)
+      mockFetch.mockResolvedValueOnce({
+        ok: true,
+        headers: new Headers({ "content-type": "model/gltf-binary" }),
+        arrayBuffer: () => Promise.resolve(new ArrayBuffer(4096)),
+      });
+
+      const request = createMockPostRequest(
+        {
+          prompt: "A 3D model of a tree",
+          mediaType: "3d",
+          selectedModel: {
+            provider: "fal",
+            modelId: "fal-ai/hunyuan3d/standard",
+            displayName: "Hunyuan 3D Standard",
+          },
+        },
+        { "X-Fal-API-Key": "test-fal-key" }
+      );
+
+      const response = await POST(request);
+      const data = await response.json();
+
+      expect(response.status).toBe(200);
+      expect(data.success).toBe(true);
+      expect(data.contentType).toBe("3d");
+      expect(data.model3dUrl).toBe("https://fal.media/hunyuan3d-v2-output.glb");
+    });
+
+    it("should include Result keys in error log when no media URL found", async () => {
+      const consoleSpy = vi.spyOn(console, "error").mockImplementation(() => {});
+
+      // Schema fetch
+      mockFetch.mockResolvedValueOnce({
+        ok: true,
+        json: () => Promise.resolve({ models: [] }),
+      });
+
+      // Queue submit
+      mockFetch.mockResolvedValueOnce({
+        ok: true,
+        json: () => Promise.resolve({ request_id: "test-req-id" }),
+      });
+      // Status poll → COMPLETED
+      mockFetch.mockResolvedValueOnce({
+        ok: true,
+        json: () => Promise.resolve({ status: "COMPLETED" }),
+      });
+      // Result fetch returns unrecognized format
+      mockFetch.mockResolvedValueOnce({
+        ok: true,
+        json: () => Promise.resolve({ unknown_field: "data", another: 123 }),
+      });
+
+      const request = createMockPostRequest(
+        {
+          prompt: "Test prompt",
+          selectedModel: {
+            provider: "fal",
+            modelId: "fal-ai/some-model",
+            displayName: "Some Model",
+          },
+        },
+        { "X-Fal-API-Key": "test-fal-key" }
+      );
+
+      const response = await POST(request);
+      const data = await response.json();
+
+      expect(response.status).toBe(500);
+      expect(data.success).toBe(false);
+      expect(data.error).toContain("No media URL in response");
+
+      // Verify the enhanced error log includes Result keys
+      const errorCalls = consoleSpy.mock.calls;
+      const resultKeysLog = errorCalls.find(
+        (call) => typeof call[0] === "string" && call[0].includes("Result keys:")
+      );
+      expect(resultKeysLog).toBeDefined();
+      expect(resultKeysLog![0]).toContain("unknown_field");
+      expect(resultKeysLog![0]).toContain("another");
+
+      consoleSpy.mockRestore();
+    });
   });
 });
diff --git a/src/app/api/open-file/__tests__/route.test.ts b/src/app/api/open-file/__tests__/route.test.ts
new file mode 100644
index 00000000..16b85da7
--- /dev/null
+++ b/src/app/api/open-file/__tests__/route.test.ts
@@ -0,0 +1,276 @@
+// @vitest-environment node
+import { describe, it, expect, vi, beforeEach } from "vitest";
+import { NextRequest } from "next/server";
+
+// Use vi.hoisted so mock fns are available during vi.mock() hoisting
+const { mockExecFileAsync, mockStat, mockPlatform, mockHomedir } = vi.hoisted(() => ({
+  mockExecFileAsync: vi.fn(),
+  mockStat: vi.fn(),
+  mockPlatform: vi.fn(),
+  mockHomedir: vi.fn(),
+}));
+
+vi.mock(import("child_process"), async (importOriginal) => {
+  const actual = await importOriginal();
+  return {
+    ...actual,
+    execFile: vi.fn(),
+  };
+});
+
+vi.mock(import("util"), async (importOriginal) => {
+  const actual = await importOriginal();
+  return {
+    ...actual,
+    promisify: () => mockExecFileAsync,
+  };
+});
+
+vi.mock(import("fs/promises"), async (importOriginal) => {
+  const actual = await importOriginal();
+  return {
+    ...actual,
+    stat: (...args: unknown[]) => mockStat(...args),
+  };
+});
+
+vi.mock(import("os"), async (importOriginal) => {
+  const actual = await importOriginal();
+  return {
+    ...actual,
+    default: {
+      ...actual,
+      platform: () => mockPlatform(),
+      homedir: () => mockHomedir(),
+    },
+    platform: () => mockPlatform(),
+    homedir: () => mockHomedir(),
+  };
+});
+
+import { POST } from "../route";
+
+// Helper to create mock NextRequest
+function createMockRequest(
+  body: unknown,
+  headers?: Record<string, string>
+): NextRequest {
+  return {
+    json: vi.fn().mockResolvedValue(body),
+    headers: new Headers({ host: "localhost:3000", ...headers }),
+  } as unknown as NextRequest;
+}
+
+describe("/api/open-file route", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+    mockPlatform.mockReturnValue("darwin");
+    mockHomedir.mockReturnValue("/Users/testuser");
+  });
+
+  describe("localhost guard", () => {
+    it("should return 403 for non-localhost x-forwarded-for", async () => {
+      const request = createMockRequest(
+        { filePath: "/Users/testuser/file.glb" },
+        { "x-forwarded-for": "203.0.113.50", host: "localhost:3000" }
+      );
+
+      const response = await POST(request);
+      const data = await response.json();
+
+      expect(response.status).toBe(403);
+      expect(data.error).toBe("Forbidden: localhost only");
+    });
+
+    it("should return 403 for non-localhost host header", async () => {
+      const request = createMockRequest(
+        { filePath: "/Users/testuser/file.glb" },
+        { host: "example.com" }
+      );
+
+      const response = await POST(request);
+      const data = await response.json();
+
+      expect(response.status).toBe(403);
+      expect(data.error).toBe("Forbidden: localhost only");
+    });
+
+    it("should allow requests from 127.0.0.1 x-forwarded-for", async () => {
+      mockStat.mockResolvedValue({ isFile: () => true });
+      mockExecFileAsync.mockResolvedValue({ stdout: "", stderr: "" });
+
+      const request = createMockRequest(
+        { filePath: "/Users/testuser/file.glb" },
+        { "x-forwarded-for": "127.0.0.1", host: "localhost:3000" }
+      );
+
+      const response = await POST(request);
+      const data = await response.json();
+
+      expect(response.status).toBe(200);
+      expect(data.success).toBe(true);
+    });
+
+    it("should allow requests from ::1 x-forwarded-for", async () => {
+      mockStat.mockResolvedValue({ isFile: () => true });
+      mockExecFileAsync.mockResolvedValue({ stdout: "", stderr: "" });
+
+      const request = createMockRequest(
+        { filePath: "/Users/testuser/file.glb" },
+        { "x-forwarded-for": "::1", host: "localhost:3000" }
+      );
+
+      const response = await POST(request);
+      const data = await response.json();
+
+      expect(response.status).toBe(200);
+      expect(data.success).toBe(true);
+    });
+
+    it("should allow requests with localhost host header", async () => {
+      mockStat.mockResolvedValue({ isFile: () => true });
+      mockExecFileAsync.mockResolvedValue({ stdout: "", stderr: "" });
+
+      const request = createMockRequest(
+        { filePath: "/Users/testuser/file.glb" },
+        { host: "localhost:3000" }
+      );
+
+      const response = await POST(request);
+      const data = await response.json();
+
+      expect(response.status).toBe(200);
+      expect(data.success).toBe(true);
+    });
+  });
+
+  describe("input validation", () => {
+    it("should return 400 for missing filePath", async () => {
+      const request = createMockRequest({});
+
+      const response = await POST(request);
+      const data = await response.json();
+
+      expect(response.status).toBe(400);
+      expect(data.error).toBe("File path is required");
+    });
+
+    it("should return 400 for empty filePath", async () => {
+      const request = createMockRequest({ filePath: "" });
+
+      const response = await POST(request);
+      const data = await response.json();
+
+      expect(response.status).toBe(400);
+      expect(data.error).toBe("File path is required");
+    });
+
+    it("should return 400 for non-string filePath", async () => {
+      const request = createMockRequest({ filePath: 12345 });
+
+      const response = await POST(request);
+      const data = await response.json();
+
+      expect(response.status).toBe(400);
+      expect(data.error).toBe("File path is required");
+    });
+  });
+
+  describe("path restriction", () => {
+    it("should return 403 for path outside home directory", async () => {
+      const request = createMockRequest({ filePath: "/etc/passwd" });
+
+      const response = await POST(request);
+      const data = await response.json();
+
+      expect(response.status).toBe(403);
+      expect(data.error).toBe("Path is outside allowed directory");
+    });
+  });
+
+  describe("file validation", () => {
+    it("should return 400 when path is a directory", async () => {
+      mockStat.mockResolvedValue({ isFile: () => false });
+
+      const request = createMockRequest({
+        filePath: "/Users/testuser/generations",
+      });
+
+      const response = await POST(request);
+      const data = await response.json();
+
+      expect(response.status).toBe(400);
+      expect(data.error).toBe("Path is not a file");
+    });
+
+    it("should return 400 when file does not exist", async () => {
+      mockStat.mockRejectedValue(new Error("ENOENT"));
+
+      const request = createMockRequest({
+        filePath: "/Users/testuser/nonexistent.glb",
+      });
+
+      const response = await POST(request);
+      const data = await response.json();
+
+      expect(response.status).toBe(400);
+      expect(data.error).toBe("File does not exist");
+    });
+  });
+
+  describe("platform commands", () => {
+    it("should call 'open -R' on macOS", async () => {
+      mockPlatform.mockReturnValue("darwin");
+      mockStat.mockResolvedValue({ isFile: () => true });
+      mockExecFileAsync.mockResolvedValue({ stdout: "", stderr: "" });
+
+      const request = createMockRequest({
+        filePath: "/Users/testuser/generations/model.glb",
+      });
+
+      const response = await POST(request);
+      const data = await response.json();
+
+      expect(response.status).toBe(200);
+      expect(data.success).toBe(true);
+      expect(mockExecFileAsync).toHaveBeenCalledWith("open", [
+        "-R",
+        "/Users/testuser/generations/model.glb",
+      ]);
+    });
+
+    it("should call 'xdg-open' with parent directory on Linux", async () => {
+      mockPlatform.mockReturnValue("linux");
+      mockStat.mockResolvedValue({ isFile: () => true });
+      mockExecFileAsync.mockResolvedValue({ stdout: "", stderr: "" });
+
+      const request = createMockRequest({
+        filePath: "/Users/testuser/generations/model.glb",
+      });
+
+      const response = await POST(request);
+      const data = await response.json();
+
+      expect(response.status).toBe(200);
+      expect(data.success).toBe(true);
+      expect(mockExecFileAsync).toHaveBeenCalledWith("xdg-open", [
+        "/Users/testuser/generations",
+      ]);
+    });
+
+    it("should return 500 when command execution fails", async () => {
+      mockStat.mockResolvedValue({ isFile: () => true });
+      mockExecFileAsync.mockRejectedValue(new Error("Command not found"));
+
+      const request = createMockRequest({
+        filePath: "/Users/testuser/generations/model.glb",
+      });
+
+      const response = await POST(request);
+      const data = await response.json();
+
+      expect(response.status).toBe(500);
+      expect(data.error).toBe("Failed to open file location");
+    });
+  });
+});
diff --git a/src/app/api/save-generation/__tests__/route.test.ts b/src/app/api/save-generation/__tests__/route.test.ts
index 5999907d..4c5f3d58 100644
--- a/src/app/api/save-generation/__tests__/route.test.ts
+++ b/src/app/api/save-generation/__tests__/route.test.ts
@@ -27,7 +27,7 @@ vi.mock("@/utils/logger", () => ({
 // Store original fetch
 const originalFetch = global.fetch;
 
-import { POST } from "../route";
+import { POST, getExtensionFromUrl } from "../route";
 
 // Helper to create mock NextRequest for POST
 function createMockPostRequest(body: unknown): NextRequest {
@@ -526,3 +526,57 @@ describe("/api/save-generation route", () => {
     });
   });
 });
+
+describe("getExtensionFromUrl", () => {
+  it("should extract .glb from a CDN URL", () => {
+    expect(getExtensionFromUrl("https://cdn.example.com/model.glb")).toBe("glb");
+  });
+
+  it("should extract .obj extension", () => {
+    expect(getExtensionFromUrl("https://cdn.example.com/model.obj")).toBe("obj");
+  });
+
+  it("should extract .fbx extension", () => {
+    expect(getExtensionFromUrl("https://cdn.example.com/model.fbx")).toBe("fbx");
+  });
+
+  it("should extract .usdz extension", () => {
+    expect(getExtensionFromUrl("https://cdn.example.com/model.usdz")).toBe("usdz");
+  });
+
+  it("should extract .stl extension", () => {
+    expect(getExtensionFromUrl("https://cdn.example.com/model.stl")).toBe("stl");
+  });
+
+  it("should extract .gltf extension", () => {
+    expect(getExtensionFromUrl("https://cdn.example.com/model.gltf")).toBe("gltf");
+  });
+
+  it("should return null for unrecognized extensions", () => {
+    expect(getExtensionFromUrl("https://cdn.example.com/file.xyz")).toBeNull();
+  });
+
+  it("should return null for URLs without extensions", () => {
+    expect(getExtensionFromUrl("https://cdn.example.com/model")).toBeNull();
+  });
+
+  it("should return null for invalid URLs", () => {
+    expect(getExtensionFromUrl("not-a-url")).toBeNull();
+  });
+
+  it("should handle query strings correctly", () => {
+    expect(getExtensionFromUrl("https://cdn.example.com/model.glb?token=abc123")).toBe("glb");
+  });
+
+  it("should handle fragments correctly", () => {
+    expect(getExtensionFromUrl("https://cdn.example.com/model.glb#section")).toBe("glb");
+  });
+
+  it("should return null for URL ending with dot", () => {
+    expect(getExtensionFromUrl("https://cdn.example.com/model.")).toBeNull();
+  });
+
+  it("should not recognize zip as a 3D extension", () => {
+    expect(getExtensionFromUrl("https://cdn.example.com/model.zip")).toBeNull();
+  });
+});