app/src/components/projects/AddProjectDialog.test.tsx

@@ -0,0 +1,118 @@
+import { describe, it, expect, vi, beforeEach } from "vitest";
+import { render, screen, fireEvent, waitFor, act } from "@testing-library/react";
+import AddProjectDialog from "./AddProjectDialog";
+
+const add = vi.fn();
+
+vi.mock("../../hooks/useProjects", () => ({
+  useProjects: () => ({ add }),
+}));
+
+vi.mock("@tauri-apps/plugin-dialog", () => ({
+  open: vi.fn(async () => null),
+}));
+
+/** A promise whose resolution this test controls, so `loading` can be held open. */
+function deferred() {
+  let resolve!: (v: unknown) => void;
+  const promise = new Promise((r) => {
+    resolve = r;
+  });
+  return { promise, resolve };
+}
+
+function fillValidForm() {
+  fireEvent.change(screen.getByLabelText("Project name"), {
+    target: { value: "my-project" },
+  });
+  fireEvent.change(screen.getByLabelText("Folder 1 host path"), {
+    target: { value: "/home/user/my-project" },
+  });
+}
+
+function submitButton() {
+  return screen.getByRole("button", { name: /Add Project|Adding/ });
+}
+
+describe("AddProjectDialog", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+  });
+
+  it("adds the project with the name and folder entered", async () => {
+    add.mockResolvedValue({ id: "p1" });
+    const onClose = vi.fn();
+    render(<AddProjectDialog onClose={onClose} />);
+    fillValidForm();
+    fireEvent.click(submitButton());
+    await waitFor(() =>
+      expect(add).toHaveBeenCalledWith("my-project", [
+        { host_path: "/home/user/my-project", mount_name: "my-project" },
+      ]),
+    );
+    await waitFor(() => expect(onClose).toHaveBeenCalled());
+  });
+
+  it("keeps the submit button announced, and explains why, while adding", async () => {
+    const { promise, resolve } = deferred();
+    add.mockReturnValue(promise);
+    render(<AddProjectDialog onClose={vi.fn()} />);
+    fillValidForm();
+    fireEvent.click(submitButton());
+
+    // Native `disabled` would remove the button from the accessibility tree
+    // exactly when it has something to say.
+    await waitFor(() =>
+      expect(submitButton()).toHaveAttribute("aria-disabled", "true"),
+    );
+    expect(submitButton()).not.toBeDisabled();
+    expect(submitButton()).toHaveAccessibleDescription(/being added/i);
+
+    await act(async () => resolve({ id: "p1" }));
+  });
+
+  it("ignores clicks and Enter/Space on the submit button while adding", async () => {
+    const { promise, resolve } = deferred();
+    add.mockReturnValue(promise);
+    render(<AddProjectDialog onClose={vi.fn()} />);
+    fillValidForm();
+    fireEvent.click(submitButton());
+    await waitFor(() =>
+      expect(submitButton()).toHaveAttribute("aria-disabled", "true"),
+    );
+
+    fireEvent.click(submitButton());
+    fireEvent.keyDown(submitButton(), { key: "Enter" });
+    fireEvent.keyDown(submitButton(), { key: " " });
+    expect(add).toHaveBeenCalledTimes(1);
+
+    await act(async () => resolve({ id: "p1" }));
+  });
+
+  it("ignores a form submit raised from elsewhere while adding", async () => {
+    const { promise, resolve } = deferred();
+    add.mockReturnValue(promise);
+    render(<AddProjectDialog onClose={vi.fn()} />);
+    fillValidForm();
+    fireEvent.click(submitButton());
+    await waitFor(() =>
+      expect(submitButton()).toHaveAttribute("aria-disabled", "true"),
+    );
+
+    // Enter in a text field submits a form regardless of the submit button's
+    // state, so the handler has to guard itself too.
+    // Modal portals to document.body, so the form is not under `container`.
+    const form = document.querySelector("form");
+    expect(form).not.toBeNull();
+    fireEvent.submit(form!);
+    expect(add).toHaveBeenCalledTimes(1);
+
+    await act(async () => resolve({ id: "p1" }));
+  });
+
+  it("leaves the submit button plainly available when idle", () => {
+    render(<AddProjectDialog onClose={vi.fn()} />);
+    expect(submitButton()).not.toHaveAttribute("aria-disabled");
+    expect(submitButton()).toHaveAccessibleDescription("");
+  });
+});

app/src/components/projects/AddProjectDialog.tsx

@@ -55,6 +55,10 @@ export default function AddProjectDialog({ onClose }: Props) {
 
   const handleSubmit = async (e?: React.FormEvent) => {
     if (e) e.preventDefault();
+    // The submit button is `aria-disabled` rather than `disabled` while an add
+    // is in flight, and Enter inside a text field submits the form without
+    // touching the button at all. Both routes end here, so the guard does too.
+    if (loading) return;
     if (!name.trim()) {
       setError("Project name is required");
       return;
@@ -97,7 +101,19 @@ export default function AddProjectDialog({ onClose }: Props) {
           <Button size="md" variant="ghost" onClick={onClose}>
             Cancel
           </Button>
-          <Button size="md" variant="primary" type="submit" form={formId} disabled={loading}>
+          <Button
+            size="md"
+            variant="primary"
+            type="submit"
+            form={formId}
+            unavailable={loading}
+            unavailableReason="The project is being added. Wait for it to finish."
+            title={
+              loading
+                ? "The project is being added. Wait for it to finish."
+                : undefined
+            }
+          >
             {loading ? "Adding…" : "Add Project"}
           </Button>
         </>

app/src/components/projects/ProjectRow.test.tsx

@@ -122,14 +122,6 @@ describe("ProjectRow", () => {
   });
 
   it("only allows opening a terminal while the container runs", () => {
-    const { unmount } = render(<ProjectRow project={baseProject} />);
-    expect(
-      screen.getByRole("button", {
-        name: "Open a Claude terminal for Test Project",
-      }),
-    ).toBeDisabled();
-    unmount();
-
     render(<ProjectRow project={{ ...baseProject, status: "running" }} />);
     fireEvent.click(
       screen.getByRole("button", {
@@ -139,6 +131,38 @@ describe("ProjectRow", () => {
     expect(mockOpenClaudeTerminal).toHaveBeenCalled();
   });
 
+  it("keeps the terminal button announced, and explains why, while stopped", () => {
+    render(<ProjectRow project={baseProject} />);
+    const button = screen.getByRole("button", {
+      name: "Open a Claude terminal for Test Project",
+    });
+    // Native `disabled` would drop the button out of the accessibility tree
+    // and out of the tab order, taking the reason with it.
+    expect(button).not.toBeDisabled();
+    expect(button).toHaveAttribute("aria-disabled", "true");
+    expect(button).toHaveAccessibleDescription(/is not running/i);
+  });
+
+  it("ignores clicks and Enter/Space on the terminal button while stopped", () => {
+    render(<ProjectRow project={baseProject} />);
+    const button = screen.getByRole("button", {
+      name: "Open a Claude terminal for Test Project",
+    });
+    fireEvent.click(button);
+    fireEvent.keyDown(button, { key: "Enter" });
+    fireEvent.keyDown(button, { key: " " });
+    expect(mockOpenClaudeTerminal).not.toHaveBeenCalled();
+  });
+
+  it("drops aria-disabled once the container is running", () => {
+    render(<ProjectRow project={{ ...baseProject, status: "running" }} />);
+    const button = screen.getByRole("button", {
+      name: "Open a Claude terminal for Test Project",
+    });
+    expect(button).not.toHaveAttribute("aria-disabled");
+    expect(button).not.toHaveAccessibleDescription(/is not running/i);
+  });
+
   it("shows container progress inline rather than in a blocking modal", () => {
     setStore({ containerProgress: { "test-1": "Pulling image…" } });
     render(<ProjectRow project={{ ...baseProject, status: "starting" }} />);

app/src/components/projects/ProjectRow.tsx

@@ -3,6 +3,7 @@ import type { Project } from "../../lib/types";
 import { useAppState, homeTabKey } from "../../store/appState";
 import { useProjectActions } from "../../hooks/useProjectActions";
 import { ProjectStatusIndicator } from "../ui/StatusIndicator";
+import { useUnavailable } from "../ui/unavailable";
 
 interface Props {
   project: Project;
@@ -31,6 +32,15 @@ export default function ProjectRow({ project }: Props) {
   const isTransitioning =
     project.status === "starting" || project.status === "stopping";
 
+  // A terminal needs a running container. Saying so out loud beats a `disabled`
+  // attribute that hides the button — and the reason — from anyone not using a
+  // mouse and eyes.
+  const terminal = useUnavailable({
+    unavailable: !isRunning,
+    reason: `${project.name} is not running. Start it to open a terminal.`,
+    onClick: () => openClaudeTerminal(),
+  });
+
   return (
     <div
       className={`group relative px-2 py-1.5 rounded-[var(--radius-control)] transition-colors min-w-0 overflow-hidden ${
@@ -113,11 +123,14 @@ export default function ProjectRow({ project }: Props) {
         </button>
         <button
           type="button"
-          disabled={!isRunning}
-          onClick={() => openClaudeTerminal()}
-          title={`Open a Claude terminal for ${project.name}`}
+          {...terminal.controlProps}
+          title={
+            isRunning
+              ? `Open a Claude terminal for ${project.name}`
+              : `${project.name} is not running. Start it to open a terminal.`
+          }
           aria-label={`Open a Claude terminal for ${project.name}`}
-          className="w-6 h-6 flex items-center justify-center rounded-[var(--radius-control)] text-[var(--text-secondary)] hover:text-[var(--text-primary)] hover:bg-[var(--bg-primary)] disabled:text-[var(--text-disabled)] transition-colors"
+          className="w-6 h-6 flex items-center justify-center rounded-[var(--radius-control)] text-[var(--text-secondary)] hover:text-[var(--text-primary)] hover:bg-[var(--bg-primary)] disabled:text-[var(--text-disabled)] aria-disabled:text-[var(--text-disabled)] aria-disabled:hover:text-[var(--text-disabled)] aria-disabled:hover:bg-transparent aria-disabled:cursor-not-allowed transition-colors"
         >
           <svg
             className="w-3.5 h-3.5"
@@ -134,6 +147,7 @@ export default function ProjectRow({ project }: Props) {
             <line x1="13" y1="15" x2="17" y2="15" />
           </svg>
         </button>
+        {terminal.reasonNode}
       </div>
     </div>
   );