Harden MCP article and weight workflows

rollcalc_mcp_tools.py

@@ -6,6 +6,7 @@ from typing import Any
 
 from roll_calculation import (
     ArticleRepository,
+    calculate_material_weight,
     calculate_roll,
     get_article,
     transport_roll_inputs_from_roll_calculation,
@@ -26,6 +27,20 @@ def search_articles_result(query: str) -> dict[str, Any]:
     return ArticleRepository.load().search(query)
 
 
+def calculate_material_weight_result(
+    *,
+    roll_length_m: float,
+    width_m: float,
+    area_weight_g_m2: float,
+) -> dict[str, Any]:
+    """Delegate material-only weight calculation to the shared domain service."""
+    return calculate_material_weight(
+        roll_length_m=roll_length_m,
+        width_m=width_m,
+        area_weight_g_m2=area_weight_g_m2,
+    )
+
+
 def calculate_roll_diameter_result(
     *,
     article_number: str | None = None,