Expose product length calculation through MCP

tests/test_mcp_adapter.py

@@ -8,12 +8,14 @@ import mcp_server
 from roll_calculation import (
     ArticleRepository,
     calculate_material_weight,
+    calculate_product_length,
     calculate_roll,
     get_article,
 )
 from rollcalc_mcp_tools import (
     analyze_transport_capacity_result,
     calculate_material_weight_result,
+    calculate_product_length_result,
     calculate_roll_diameter_result,
     get_article_result,
     search_articles_result,
@@ -87,6 +89,23 @@ class McpAdapterTests(unittest.TestCase):
         self.assertEqual(result["weight_scope"], "material_only")
         self.assertAlmostEqual(result["material_weight_kg"], 1455.0239028)
 
+    def test_product_length_adapter_delegates_with_article_218500_values(self):
+        arguments = {
+            "target_roll_diameter_mm": 600.0,
+            "core_diameter_mm": 140.0,
+            "thickness_mm": 4.311611,
+            "thickness_stddev_mm": 0.249999,
+            "width_m": 6.0,
+            "area_weight_g_m2": 495.395833,
+        }
+
+        result = calculate_product_length_result(**arguments)
+
+        self.assertEqual(result, calculate_product_length(**arguments))
+        self.assertAlmostEqual(
+            result["calculation"]["average_product_length_m"], 62.0068774341
+        )
+
     def test_calculate_roll_diameter_delegates_for_normal_weighted_and_invalid_cases(self):
         for arguments in (
             {
@@ -178,6 +197,7 @@ class McpAdapterTests(unittest.TestCase):
                 "get_article",
                 "search_articles",
                 "calculate_material_weight",
+                "calculate_product_length",
                 "calculate_roll_diameter",
                 "analyze_transport_capacity",
             ],
@@ -188,6 +208,7 @@ class McpAdapterTests(unittest.TestCase):
         tools = instance._tool_manager._tools
         search_tool = tools["search_articles"]
         material_weight_tool = tools["calculate_material_weight"]
+        product_length_tool = tools["calculate_product_length"]
         roll_schema = tools["calculate_roll_diameter"].parameters
         transport_tool = tools["analyze_transport_capacity"]
         transport_schema = transport_tool.parameters
@@ -202,6 +223,19 @@ class McpAdapterTests(unittest.TestCase):
             ["roll_length_m", "width_m", "area_weight_g_m2"],
         )
         self.assertNotIn("core_diameter_mm", material_weight_schema["properties"])
+        product_length_schema = product_length_tool.parameters
+        self.assertEqual(
+            product_length_schema["required"],
+            [
+                "target_roll_diameter_mm",
+                "core_diameter_mm",
+                "thickness_mm",
+            ],
+        )
+        self.assertEqual(
+            product_length_schema["properties"]["target_roll_diameter_mm"]["type"],
+            "number",
+        )
 
         self.assertNotIn("include_roll_weight", roll_schema["properties"])
         preset_schema = transport_schema["properties"]["transport_preset"]
@@ -294,6 +328,16 @@ class McpAdapterTests(unittest.TestCase):
         self.assertIn("do not infer or default one", roll_description)
         self.assertIn("call calculate_material_weight instead", roll_description)
 
+        product_length_description = product_length_tool.description
+        for text in (
+            "required product/roll length for a target outer roll diameter",
+            "do not infer a missing core diameter, thickness, width, area weight, or article",
+            "minimum, average, and maximum length ranges",
+            "material-weight ranges",
+            "use calculate_roll_diameter for the reverse direction",
+        ):
+            self.assertIn(text, product_length_description)
+
 
 if __name__ == "__main__":
     unittest.main()