Fix all mypy type errors for CI

- validators.py: type enum_class parameter as type[enum.Enum]
- dialog_handler.py: ignore attr-defined for Windows-only WINFUNCTYPE
- vba.py, results.py: add type: ignore for safe indexed assignments
- parameters.py, optimization.py, import_export.py: use Callable instead
  of builtin callable in type annotations
- materials.py, optimization.py: add list type annotations
- tools/__init__.py: cast lambda to ToolHandler

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: RFingAdam

src/mcp_cst_studio/dialog_handler.py

@@ -40,7 +40,7 @@
     user32 = ctypes.windll.user32  # type: ignore[attr-defined]
 
     # Callback type for EnumWindows / EnumChildWindows
-    WNDENUMPROC = ctypes.WINFUNCTYPE(wintypes.BOOL, wintypes.HWND, wintypes.LPARAM)
+    WNDENUMPROC = ctypes.WINFUNCTYPE(wintypes.BOOL, wintypes.HWND, wintypes.LPARAM)  # type: ignore[attr-defined]
 
     # Constants
     WM_CLOSE = 0x0010

src/mcp_cst_studio/tools/__init__.py

@@ -13,7 +13,7 @@
 from __future__ import annotations
 
 import logging
-from typing import TYPE_CHECKING, Awaitable, Callable
+from typing import TYPE_CHECKING, Awaitable, Callable, cast
 
 from mcp.types import TextContent, Tool
 
@@ -57,8 +57,9 @@ def add_module(
         for tool in tools:
             self._tools.append(tool)
             # Bind *client* at registration time so each call gets the right ref
-            self._handlers[tool.name] = (
-                lambda name, args, _h=handle_fn, _c=client: _h(name, args, _c)
+            self._handlers[tool.name] = cast(
+                ToolHandler,
+                lambda name, args, _h=handle_fn, _c=client: _h(name, args, _c),
             )
 
     # -- internal: wire into the MCP server --

src/mcp_cst_studio/tools/import_export.py

@@ -7,7 +7,7 @@
 from __future__ import annotations
 
 import json
-from typing import TYPE_CHECKING
+from typing import TYPE_CHECKING, Callable
 
 from mcp.types import TextContent, Tool
 
@@ -335,7 +335,7 @@ def _build_export_farfield(args: dict) -> str:
 # Dispatch table
 # ---------------------------------------------------------------------------
 
-_HANDLERS: dict[str, callable] = {
+_HANDLERS: dict[str, Callable[..., str]] = {
     "cst_import_cad": _build_import_cad,
     "cst_export_cad": _build_export_cad,
     "cst_import_touchstone": _build_import_touchstone,

src/mcp_cst_studio/tools/materials.py

@@ -832,7 +832,7 @@ def _handle_get_material_info(args: dict) -> list[TextContent]:
     if mat is None:
         # List available names to help the user
         db = _load_material_db()
-        available = []
+        available: list[str] = []
         for cat_list in db.values():
             available.extend(m["name"] for m in cat_list)
         return [TextContent(

src/mcp_cst_studio/tools/optimization.py

@@ -17,7 +17,7 @@
 import math
 import os
 import tempfile
-from typing import TYPE_CHECKING
+from typing import TYPE_CHECKING, Any, Callable
 
 from mcp.types import TextContent, Tool
 
@@ -363,7 +363,7 @@ def _find_resonances(
 
     Returns list of {freq_ghz, s11_db, vswr} for each detected resonance.
     """
-    resonances = []
+    resonances: list[dict] = []
     n = len(s11_db)
     if n < 3:
         return resonances
@@ -1445,7 +1445,7 @@ def _build_impedance_vba(port: int) -> str:
 # Dispatch
 # ---------------------------------------------------------------------------
 
-_HANDLERS: dict[str, callable] = {
+_HANDLERS: dict[str, Callable[..., Any]] = {
     "cst_evaluate_antenna": _handle_evaluate,
     "cst_analyze_impedance": _handle_analyze_impedance,
     "cst_refine_antenna": _handle_refine,

src/mcp_cst_studio/tools/parameters.py

@@ -7,7 +7,7 @@
 from __future__ import annotations
 
 import json
-from typing import TYPE_CHECKING
+from typing import TYPE_CHECKING, Callable
 
 from mcp.types import TextContent, Tool
 
@@ -934,7 +934,7 @@ def _build_parameter_interpolation(args: dict) -> str:
 # Dispatch table
 # ---------------------------------------------------------------------------
 
-_HANDLERS: dict[str, callable] = {
+_HANDLERS: dict[str, Callable[..., str]] = {
     "cst_set_parameter": _build_set_parameter,
     "cst_get_parameter": _build_get_parameter,
     "cst_list_parameters": _build_list_parameters,

src/mcp_cst_studio/tools/results.py

@@ -2263,7 +2263,7 @@ async def _handle_impl(name: str, arguments: dict, client: CSTClient) -> list[Te
     # cst_list_results
     # ------------------------------------------------------------------
     if name == "cst_list_results":
-        tree_path = arguments.get("tree_path")
+        tree_path = arguments.get("tree_path")  # type: ignore[assignment]
 
         if client.connected:
             vba = _build_list_results_vba(tree_path)

src/mcp_cst_studio/tools/vba.py

@@ -247,7 +247,7 @@ def _handle_list_vba_objects(args: dict) -> dict:
     # Return all categories with their objects
     result = {"status": "ok", "categories": {}}
     for cat, objects in ref.items():
-        result["categories"][cat] = {
+        result["categories"][cat] = {  # type: ignore[index]
             name: data.get("description", "")
             for name, data in objects.items()
         }

src/mcp_cst_studio/validators.py

@@ -2,6 +2,7 @@
 
 from __future__ import annotations
 
+import enum
 import re
 
 # VBA commands that could be used for injection attacks
@@ -133,7 +134,7 @@ def validate_port_number(port: int) -> int:
     return port
 
 
-def validate_enum_value(value: str, enum_class: type, label: str = "value") -> str:
+def validate_enum_value(value: str, enum_class: type[enum.Enum], label: str = "value") -> str:
     """Validate that a string matches an enum value."""
     valid = [e.value for e in enum_class]
     if value not in valid: