fix: skip init prompts when stdin is not a TTY

nitrostack/cli/main.py

@@ -1256,6 +1256,9 @@ def init_project(name: str = None, template: str = None, skip_install: bool = Fa
 
     # 2. Overwrite check
     if os.path.exists(name):
+        if not sys.stdin.isatty():
+            print(f"Error: Directory '{name}' already exists.")
+            sys.exit(1)
         sys.stdout.write(f"\033[32m? \033[1;37mDirectory '{name}' already exists. Overwrite?\033[0m (Yes/No) [No]: ")
         sys.stdout.flush()
         ans = sys.stdin.readline().strip().lower()
@@ -1270,9 +1273,13 @@ def init_project(name: str = None, template: str = None, skip_install: bool = Fa
     else:
         template = _resolve_template(template)
 
-    # 4. Description and Author
-    description = _prompt("Description", "My awesome MCP server")
-    author = _prompt("Author", "developer")
+    # 4. Description and Author — never block when stdin is not a TTY (Studio / CI).
+    if sys.stdin.isatty():
+        description = _prompt("Description", "My awesome MCP server")
+        author = _prompt("Author", "developer")
+    else:
+        description = "My awesome MCP server"
+        author = "developer"
 
     # 5. Install dependencies (Y/n). --skip-install skips the prompt.
     if skip_install:

tests/test_cli_studio_noninteractive.py

@@ -0,0 +1,108 @@
+"""Studio generate-wizard contract: init must not block on inherited stdin.
+
+NitroStudio step 4 of 5 used to hang because `nitrostack-py init --skip-install`
+still prompted Description/Author via readline() on an inherited stdin that
+never wrote. --skip-install only skips dependency install.
+
+These tests spawn the real CLI with stdin left open (PIPE, never written, never
+closed) so they fail if prompts return.
+"""
+from __future__ import annotations
+
+import os
+import subprocess
+import sys
+import tempfile
+import threading
+import time
+from pathlib import Path
+
+ROOT = os.path.abspath(os.path.join(os.path.dirname(__file__), ".."))
+
+
+def _cli_env():
+    env = os.environ.copy()
+    env["PYTHONPATH"] = ROOT
+    env["PYTHONUNBUFFERED"] = "1"
+    return env
+
+
+def _run_init_open_stdin(cwd: str, extra_args: list[str], timeout: float = 20.0):
+    """Spawn init with stdin PIPE left open. Do not write or close it."""
+    proc = subprocess.Popen(
+        [sys.executable, "-m", "nitrostack.cli.main", *extra_args],
+        cwd=cwd,
+        stdin=subprocess.PIPE,
+        stdout=subprocess.PIPE,
+        stderr=subprocess.PIPE,
+        env=_cli_env(),
+    )
+    chunks_out: list[bytes] = []
+    chunks_err: list[bytes] = []
+
+    def _drain(stream, bucket):
+        try:
+            while True:
+                data = stream.read(4096)
+                if not data:
+                    break
+                bucket.append(data)
+        except Exception:
+            pass
+
+    threading.Thread(target=_drain, args=(proc.stdout, chunks_out), daemon=True).start()
+    threading.Thread(target=_drain, args=(proc.stderr, chunks_err), daemon=True).start()
+
+    deadline = time.time() + timeout
+    while proc.poll() is None:
+        if time.time() > deadline:
+            proc.kill()
+            proc.wait(timeout=5)
+            stdout = b"".join(chunks_out).decode("utf-8", "replace")
+            stderr = b"".join(chunks_err).decode("utf-8", "replace")
+            raise TimeoutError(
+                f"CLI hung for {timeout}s on open unused stdin\n"
+                f"stdout:\n{stdout}\nstderr:\n{stderr}"
+            )
+        time.sleep(0.05)
+
+    stdout = b"".join(chunks_out).decode("utf-8", "replace")
+    stderr = b"".join(chunks_err).decode("utf-8", "replace")
+    return proc.returncode, stdout, stderr
+
+
+def test_init_skip_install_does_not_hang_on_open_unused_stdin():
+    tmp = tempfile.mkdtemp(prefix="nitro-cli-studio-")
+    try:
+        code, stdout, stderr = _run_init_open_stdin(
+            tmp,
+            ["init", "studio_demo", "--template", "python-starter", "--skip-install"],
+        )
+        assert code == 0, f"exit {code}\n{stdout}\n{stderr}"
+        project = Path(tmp) / "studio_demo"
+        assert (project / "main.py").is_file()
+        assert (project / "app_module.py").is_file()
+        req = (project / "requirements.txt").read_text(encoding="utf-8")
+        assert "nitrostack" in req.lower()
+    finally:
+        import shutil
+
+        shutil.rmtree(tmp, ignore_errors=True)
+
+
+def test_init_existing_dir_exits_without_overwrite_prompt():
+    tmp = tempfile.mkdtemp(prefix="nitro-cli-exists-")
+    try:
+        os.mkdir(os.path.join(tmp, "already"))
+        code, stdout, stderr = _run_init_open_stdin(
+            tmp,
+            ["init", "already", "--template", "python-starter", "--skip-install"],
+            timeout=15.0,
+        )
+        assert code != 0
+        combined = (stdout + stderr).lower()
+        assert "already exists" in combined
+    finally:
+        import shutil
+
+        shutil.rmtree(tmp, ignore_errors=True)