diff --git a/ui/storybook/fixtures/workFolders.test.ts b/ui/storybook/fixtures/workFolders.test.ts
new file mode 100644
index 0000000000..b286ad521a
--- /dev/null
+++ b/ui/storybook/fixtures/workFolders.test.ts
@@ -0,0 +1,102 @@
+import { describe, expect, it } from "vitest";
+import type { WorkFile } from "@paperclipai/shared";
+import { createWorkFolderFixture } from "./workFolders";
+
+const root =
+  "http://storybook.test/api/companies/company-storybook/work-folders/task/issue-storybook-1";
+type Fixture = ReturnType<typeof createWorkFolderFixture>;
+function request(fixture: Fixture, suffix = "", init?: RequestInit) {
+  return fixture.handle(new Request(`${root}${suffix}`, init));
+}
+async function files(fixture: Fixture, trash = false): Promise<WorkFile[]> {
+  return (await (await request(fixture, `?trash=${trash}`))!.json()).files;
+}
+function operation(
+  fixture: Fixture,
+  action: string,
+  fields: Record<string, string>,
+) {
+  return request(fixture, "/operations", {
+    method: "POST",
+    body: JSON.stringify({ action, ...fields }),
+  });
+}
+
+describe("work-folder Storybook fixtures", () => {
+  it("keeps uploads within one owner and resets them for the next story", async () => {
+    const fixture = createWorkFolderFixture("empty");
+    const bytes = new Uint8Array([0, 255, 128, 10]);
+    await request(fixture, "/content?path=nested%2Fsample.bin", {
+      method: "PUT",
+      body: bytes,
+    });
+    const downloaded = await request(
+      fixture,
+      "/content?path=nested%2Fsample.bin",
+    );
+    expect(new Uint8Array(await downloaded!.arrayBuffer())).toEqual(bytes);
+    expect(await files(fixture)).toHaveLength(1);
+    const otherOwner = await fixture.handle(
+      new Request(root.replace("/task/issue-storybook-1", "/user/user-board")),
+    );
+    expect((await otherOwner!.json()).files).toEqual([]);
+    expect(await files(createWorkFolderFixture("empty"))).toEqual([]);
+    expect(
+      await fixture.handle(
+        new Request(
+          "http://storybook.test/api/companies/real-company/work-folders/task/task-1",
+        ),
+      ),
+    ).toBeNull();
+  });
+
+  it("restores a deleted directory and purges its content without affecting siblings", async () => {
+    const fixture = createWorkFolderFixture("empty");
+    await operation(fixture, "mkdir", { path: "notes" });
+    await request(fixture, "/content?path=notes%2Fempty.txt", {
+      method: "PUT",
+      body: "",
+    });
+    await request(fixture, "/content?path=notes-extra.txt", {
+      method: "PUT",
+      body: "Keep me",
+    });
+    await operation(fixture, "delete", { path: "notes" });
+    expect((await files(fixture)).map((file) => file.path)).toEqual([
+      "notes-extra.txt",
+    ]);
+    const directory = (await files(fixture, true)).find(
+      (file) => file.kind === "directory",
+    )!;
+    await operation(fixture, "restore", { fileId: directory.id });
+    expect(await files(fixture, true)).toEqual([]);
+    expect(
+      await (await request(fixture, "/content?path=notes%2Fempty.txt"))!.text(),
+    ).toBe("");
+    await operation(fixture, "delete", { path: "notes" });
+    await operation(fixture, "purge", { fileId: directory.id });
+    expect(await files(fixture, true)).toEqual([]);
+    expect(
+      (await request(fixture, "/content?path=notes%2Fempty.txt"))!.status,
+    ).toBe(404);
+    expect(
+      await (await request(fixture, "/content?path=notes-extra.txt"))!.text(),
+    ).toBe("Keep me");
+  });
+
+  it("preserves existing content when an upload failure is demonstrated", async () => {
+    const fixture = createWorkFolderFixture("uploadFailed");
+    const before = await (await request(
+      fixture,
+      "/content?path=README.md",
+    ))!.text();
+    const response = await request(fixture, "/content?path=README.md", {
+      method: "PUT",
+      body: "replacement",
+    });
+    expect(response!.status).toBe(503);
+    expect(
+      await (await request(fixture, "/content?path=README.md"))!.text(),
+    ).toBe(before);
+  });
+});
diff --git a/ui/storybook/fixtures/workFolders.ts b/ui/storybook/fixtures/workFolders.ts
index f8a2ebbb23..7949c39ea9 100644
--- a/ui/storybook/fixtures/workFolders.ts
+++ b/ui/storybook/fixtures/workFolders.ts
@@ -180,6 +180,11 @@ export function createWorkFolderFixture(
     }
     const path = url.searchParams.get("path") ?? "";
     if (action === "content" && request.method === "GET") {
+      if (
+        !state.files.some((file) => file.path === path && file.kind === "file")
+      ) {
+        return fail("File not found", 404);
+      }
       if (path === "assets/paperclip.png")
         return fetch("/android-chrome-192x192.png", { signal: request.signal });
       const blob = state.contents.get(path);
@@ -245,8 +250,12 @@ export function createWorkFolderFixture(
         state.files.forEach((f) => {
           if (inDeletedTree(f)) f.deletedAt = null;
         });
-      if (op.action === "purge")
+      if (op.action === "purge") {
+        for (const file of state.files.filter(inDeletedTree)) {
+          state.contents.delete(file.path);
+        }
         state.files = state.files.filter((f) => !inDeletedTree(f));
+      }
     } else return fail("Unsupported fixture operation", 405);
     state.changed = true;
     return Response.json({ ok: true });