fix(integrations): resolve .cmd/.bat shims before subprocess.run

On Windows, ``shutil.which`` honors ``PATHEXT`` and locates wrappers
like ``cursor-agent.cmd`` and ``codex.cmd``, but Python's
``subprocess.run`` calls ``CreateProcess`` which does **not** consult
``PATHEXT`` and therefore fails with ``WinError 2`` on a bare argv
like ``[cursor-agent, ...]``.

Resolve ``exec_args[0]`` via ``shutil.which`` in
``IntegrationBase.dispatch_command`` so ``.cmd``/``.bat`` shims work
transparently. On POSIX this is a no-op for absolute paths and a
harmless lookup otherwise.

Verified locally on Windows 10 + cursor-agent 2026.05.16:
without this fix, ``specify workflow run speckit --input
integration=cursor-agent`` fails with ``FileNotFoundError`` even
after the cursor-agent integration starts producing valid exec
args (per the prior commit on this branch).

Tests:

* New: 2 cursor-agent tests pin the shim-resolution + passthrough
  behavior (``test_dispatch_command_resolves_cmd_shim_for_subprocess``
  and ``test_dispatch_command_passthrough_when_shutil_which_finds_nothing``).
* Updated: ``tests/test_workflows.py::TestCommandStep::test_dispatch_with_mock_cli``
  was mocking ``shutil.which`` only at the ``command`` step level
  and not at the ``base`` level, which made it environment-sensitive
  (fails locally when the real ``claude`` CLI is on PATH).  Added the
  matching base-level patch and updated the argv-assertion to reflect
  the resolved path. ``test_dispatch_failure_returns_failed_status``
  gets the same patch for consistency.
* Full repo: 2867 passed, 0 regression from this PR. The 12 remaining
  pre-existing failures are unrelated Windows ``symlink`` privilege
  failures (``WinError 1314``) on a non-admin Windows runner.

Co-authored-by: Cursor <cursoragent@cursor.com>

Author: 刘一

src/specify_cli/integrations/base.py

@@ -202,6 +202,16 @@ def dispatch_command(
             )
             raise NotImplementedError(msg)
 
+        # Windows: ``subprocess.run`` calls ``CreateProcess`` which does not
+        # consult ``PATHEXT``, so a bare command name like ``cursor-agent``
+        # that resolves to ``cursor-agent.cmd`` fails with ``WinError 2``.
+        # Resolve via ``shutil.which`` (which does honor ``PATHEXT``) so
+        # ``.cmd``/``.bat`` shims work transparently.  On POSIX this is a
+        # no-op for absolute paths and a harmless lookup otherwise.
+        resolved = shutil.which(exec_args[0])
+        if resolved:
+            exec_args = [resolved, *exec_args[1:]]
+
         cwd = str(project_root) if project_root else None
 
         if stream:

tests/integrations/test_integration_cursor_agent.py

@@ -158,3 +158,55 @@ def test_build_command_invocation_uses_hyphenated_skill_name(self):
         assert i.build_command_invocation("speckit.plan", "feature-x") == "/speckit-plan feature-x"
         assert i.build_command_invocation("plan") == "/speckit-plan"
 
+    def test_dispatch_command_resolves_cmd_shim_for_subprocess(self):
+        """``.cmd`` shims must be resolved to their full path before ``subprocess.run``.
+
+        ``cursor-agent`` (and other npm-installed CLIs on Windows) ship as
+        ``cursor-agent.cmd`` wrappers.  ``shutil.which`` honors ``PATHEXT``
+        and finds them, but Python's ``subprocess.run`` calls
+        ``CreateProcess`` which does **not** consult ``PATHEXT`` and fails
+        with ``WinError 2`` on a bare ``["cursor-agent", ...]`` argv.  The
+        fix in ``base.py::dispatch_command`` resolves ``exec_args[0]`` via
+        ``shutil.which`` so the full ``.cmd`` path is what reaches
+        ``CreateProcess``.
+        """
+        from unittest.mock import patch, MagicMock
+        i = get_integration("cursor-agent")
+
+        mock_result = MagicMock()
+        mock_result.returncode = 0
+        mock_result.stdout = "ok"
+        mock_result.stderr = ""
+
+        fake_path = r"C:\Users\foo\AppData\Local\cursor-agent\cursor-agent.CMD"
+        with patch(
+            "specify_cli.integrations.base.shutil.which", return_value=fake_path
+        ), patch("subprocess.run", return_value=mock_result) as mock_run:
+            result = i.dispatch_command(
+                "speckit.plan", args="feature-x", stream=False, timeout=5
+            )
+
+        assert result["exit_code"] == 0
+        argv = mock_run.call_args[0][0]
+        assert argv[0] == fake_path, f"expected resolved .CMD path, got: {argv[0]!r}"
+        assert argv[1:4] == ["-p", "--trust", "/speckit-plan feature-x"]
+
+    def test_dispatch_command_passthrough_when_shutil_which_finds_nothing(self):
+        """If ``shutil.which`` returns ``None``, leave argv unchanged so the
+        existing ``FileNotFoundError`` path remains observable to callers."""
+        from unittest.mock import patch, MagicMock
+        i = get_integration("cursor-agent")
+
+        mock_result = MagicMock()
+        mock_result.returncode = 0
+        mock_result.stdout = ""
+        mock_result.stderr = ""
+
+        with patch(
+            "specify_cli.integrations.base.shutil.which", return_value=None
+        ), patch("subprocess.run", return_value=mock_result) as mock_run:
+            i.dispatch_command("speckit.plan", stream=False, timeout=5)
+
+        argv = mock_run.call_args[0][0]
+        assert argv[0] == "cursor-agent"
+

tests/test_workflows.py

@@ -555,15 +555,18 @@ def test_dispatch_with_mock_cli(self, tmp_path, monkeypatch):
         mock_result.stderr = ""
 
         with patch("specify_cli.workflows.steps.command.shutil.which", return_value="/usr/local/bin/claude"), \
+             patch("specify_cli.integrations.base.shutil.which", return_value="/usr/local/bin/claude"), \
              patch("subprocess.run", return_value=mock_result) as mock_run:
             result = step.execute(config, ctx)
 
         assert result.status == StepStatus.COMPLETED
         assert result.output["dispatched"] is True
         assert result.output["exit_code"] == 0
-        # Verify the CLI was called with -p and the skill invocation
+        # Verify the CLI was called with the resolved path (via shutil.which,
+        # which honors PATHEXT for ``.cmd``/``.bat`` shims on Windows), then
+        # ``-p`` and the skill invocation.
         call_args = mock_run.call_args
-        assert call_args[0][0][0] == "claude"
+        assert call_args[0][0][0] == "/usr/local/bin/claude"
         assert call_args[0][0][1] == "-p"
         # Claude is a SkillsIntegration so uses /speckit-specify
         assert "/speckit-specify login" in call_args[0][0][2]
@@ -592,6 +595,7 @@ def test_dispatch_failure_returns_failed_status(self, tmp_path):
         mock_result.stderr = "API error"
 
         with patch("specify_cli.workflows.steps.command.shutil.which", return_value="/usr/local/bin/claude"), \
+             patch("specify_cli.integrations.base.shutil.which", return_value="/usr/local/bin/claude"), \
              patch("subprocess.run", return_value=mock_result):
             result = step.execute(config, ctx)