perf: defer the mcp import to the mcp commands

cloudsmith_cli/cli/commands/mcp.py

@@ -1,17 +1,22 @@
 """Main command/entrypoint."""
 
+from __future__ import annotations
+
 import json
 import os
 import shutil
 import sys
 import tempfile
 from pathlib import Path
+from typing import TYPE_CHECKING
 
 import click
 import json5
 
-from ...core.mcp import server
-from ...core.mcp.data import OpenAPITool
+if TYPE_CHECKING:
+    from ...core.mcp import server
+    from ...core.mcp.data import OpenAPITool
+
 from .. import command, decorators, utils
 from .main import main
 

cloudsmith_cli/cli/decorators.py

@@ -16,7 +16,6 @@
     disabled_detectors_from_env,
     registered_detectors,
 )
-from ..core.mcp import server
 from ..core.rest import create_requests_session as _create_session
 from . import config, utils
 
@@ -627,6 +626,8 @@ def initialise_mcp(f):
     @click.pass_context
     @functools.wraps(f)
     def wrapper(ctx, *args, **kwargs):
+        from ..core.mcp import server
+
         opts = kwargs.get("opts")
 
         all_tools = kwargs.pop("all_tools")

cloudsmith_cli/cli/tests/test_startup_imports.py

@@ -0,0 +1,37 @@
+"""Tests that a CLI import does not load heavy dependencies.
+
+The credential helpers run the CLI on every package-manager request, so
+module-level imports are the dominant startup cost. These tests import the
+CLI in a subprocess and inspect ``sys.modules``.
+"""
+
+import json
+import subprocess
+import sys
+
+HEAVY_PREFIXES = ("mcp", "httpx")
+
+
+def modules_loaded_by_cli_import():
+    code = (
+        "import json, sys\n"
+        "import cloudsmith_cli.cli.commands\n"
+        "print(json.dumps(sorted(sys.modules)))\n"
+    )
+    result = subprocess.run(
+        [sys.executable, "-c", code],
+        capture_output=True,
+        text=True,
+    )
+    assert result.returncode == 0, result.stderr
+    return json.loads(result.stdout)
+
+
+def test_cli_import_does_not_load_heavy_modules():
+    modules = modules_loaded_by_cli_import()
+    heavy = [
+        name
+        for name in modules
+        if any(name == p or name.startswith(p + ".") for p in HEAVY_PREFIXES)
+    ]
+    assert heavy == []