Allow direct article resolution in machine max MCP

README.md

@@ -150,14 +150,18 @@ Tool calling semantics:
   width, and area weight. It requires no core diameter, does not infer one, and
   cannot return a roll diameter or a core-inclusive total weight.
 - `calculate_machine_max_product_length` composes configured machine limits
-  with the shared calculation domain. Resolve an article first, then pass its
-  properties unchanged. Its nominal maximum uses the nominal diameter limit;
+  with the shared calculation domain. With an exact article number, MCP resolves
+  its properties internally; otherwise callers pass explicit properties. Its
+  nominal maximum uses the nominal diameter limit;
   its conservative/no-warning maximum uses RollCalc's existing maximum-diameter
   thickness variation. Both also respect configured material-only maximum roll
   weight, and the domain returns the governing constraint(s), unrounded.
   Core and width incompatibility cannot be corrected by shortening and is
   returned structurally. No manufacturing increment, core/packaging/gross
-  weight, or conditional production rule is applied in V1.1.
+  weight, or conditional production rule is applied in V1.1. Its successful
+  MCP response is a compact projection: machine identity, configured maximum
+  diameter/material-weight limits, production maxima, material weights, and
+  warnings. Flask and other domain consumers retain the full diagnostic result.
 - `calculate_product_length` calculates required roll length from a target outer
   diameter, core diameter, and material thickness. Its optional thickness
   stddev returns minimum/average/maximum length ranges; optional width and area

mcp_server.py

@@ -67,15 +67,17 @@ def create_server() -> Any:
     def calculate_machine_max_product_length(
         machine: str,
         core_diameter_mm: float,
-        thickness_mm: float,
+        article_number: str | None = None,
+        thickness_mm: float | None = None,
         thickness_stddev_mm: float | None = None,
         product_width_m: float | None = None,
         area_weight_g_m2: float | None = None,
     ) -> dict[str, Any]:
-        """Calculate deterministic maximum product length for a configured production machine. Use this for maximum roll/product length, how much product fits on a machine roll, or maximum length without a diameter warning. Resolve the article first with search_articles/get_article when needed, then pass its thickness, thickness standard deviation, width, and area weight exactly. Do not supply or invent machine limits, rearrange roll or weight formulas, calculate a weight-limited length, or compare candidate limits yourself: this tool returns nominal and conservative/no-warning production maxima and their governing constraints. Report incompatibility rather than substituting another core or width, and ask for returned missing inputs rather than inventing them."""
+        """Calculate deterministic maximum product length for a configured production machine. With an exact article_number, call this directly with machine and caller-supplied core_diameter_mm; do not call get_article merely to copy properties. Otherwise supply explicit material properties. Never mix article_number with material properties. For a product name, use search_articles; if candidates are multiple, ask the user to select an article number. Do not supply or invent machine limits or substitute a core or width; this returns nominal and conservative/no-warning production maxima and governing constraints."""
         return calculate_machine_max_product_length_result(
             machine=machine,
             core_diameter_mm=core_diameter_mm,
+            article_number=article_number,
             thickness_mm=thickness_mm,
             thickness_stddev_mm=thickness_stddev_mm,
             product_width_m=product_width_m,

rollcalc_mcp_tools.py

@@ -64,13 +64,49 @@ def calculate_machine_max_product_length_result(
     *,
     machine: str,
     core_diameter_mm: float,
-    thickness_mm: float,
+    article_number: str | None = None,
+    thickness_mm: float | None = None,
     thickness_stddev_mm: float | None = None,
     product_width_m: float | None = None,
     area_weight_g_m2: float | None = None,
 ) -> dict[str, Any]:
-    """Delegate machine-aware maximum product length to the shared domain."""
-    return calculate_machine_max_product_length(
+    """Return the compact MCP view, resolving one exact article when supplied."""
+    explicit_material = {
+        "thickness_mm": thickness_mm,
+        "thickness_stddev_mm": thickness_stddev_mm,
+        "product_width_m": product_width_m,
+        "area_weight_g_m2": area_weight_g_m2,
+    }
+    if article_number is not None:
+        mixed_fields = [
+            field for field, value in explicit_material.items() if value is not None
+        ]
+        if mixed_fields:
+            return {
+                "status": "invalid_parameter",
+                "invalid": [{
+                    "field": "article_number",
+                    "message": (
+                        "cannot be combined with explicit material properties: "
+                        + ", ".join(mixed_fields)
+                    ),
+                }],
+            }
+        article_result = get_article(article_number)
+        if article_result["status"] != "resolved":
+            return article_result
+        article = article_result["article"]
+        result = calculate_machine_max_product_length(
+            machine=machine,
+            core_diameter_mm=core_diameter_mm,
+            thickness_mm=article["thickness_mm"],
+            thickness_stddev_mm=article["thickness_stddev_mm"],
+            product_width_m=article["width_m"],
+            area_weight_g_m2=article["area_weight_g_m2"],
+        )
+        return project_machine_max_product_length_result(result, article=article)
+
+    result = calculate_machine_max_product_length(
         machine=machine,
         core_diameter_mm=core_diameter_mm,
         thickness_mm=thickness_mm,
@@ -78,6 +114,45 @@ def calculate_machine_max_product_length_result(
         product_width_m=product_width_m,
         area_weight_g_m2=area_weight_g_m2,
     )
+    return project_machine_max_product_length_result(result)
+
+
+def project_machine_max_product_length_result(
+    result: dict[str, Any],
+    *,
+    article: dict[str, Any] | None = None,
+) -> dict[str, Any]:
+    """Project successful maximum-length results for MCP without diagnostics.
+
+    The shared domain result deliberately contains detailed verification reports.
+    They remain available to Flask and other consumers, but duplicate machine
+    metadata and checks are unnecessary in the MCP response.
+    """
+    if result.get("status") != "success":
+        return result
+
+    machine = result["machine"]
+    constraints = machine["constraints"]
+    projection = {
+        "status": result["status"],
+        "machine": {"id": machine["id"], "name": machine["name"]},
+        "weight_scope": result["weight_scope"],
+        "machine_limits": {
+            "maximum_roll_diameter_mm": constraints["roll_diameter_mm"]["maximum"]
+            if constraints["roll_diameter_mm"] is not None else None,
+            "maximum_material_roll_weight_kg": constraints["roll_weight_kg"]["maximum"]
+            if constraints["roll_weight_kg"] is not None else None,
+        },
+        "production_maximums": result["production_maximums"],
+        "material_weights_kg": result["material_weights_kg"],
+        "warnings": result["warnings"],
+    }
+    if article is not None:
+        projection["article"] = {
+            "number": article["number"],
+            "name": article["name"],
+        }
+    return projection
 
 
 def calculate_material_weight_result(

tests/test_calculation_api.py

@@ -5,6 +5,7 @@ import unittest
 from unittest.mock import patch
 
 import app as rollcalc_app
+from machine_constraints import calculate_machine_max_product_length
 
 
 class CalculationApiTests(unittest.TestCase):
@@ -140,26 +141,49 @@ class CalculationApiTests(unittest.TestCase):
         self.assertEqual(result["warning_constraints"], ["roll_diameter_mm"])
 
     def test_machine_maximum_length_endpoint_is_authenticated_and_structured(self):
+        payload = {
+            "machine": "K7",
+            "core_diameter_mm": 133,
+            "thickness_mm": 4.311611,
+            "thickness_stddev_mm": 0.249999,
+            "product_width_m": 6,
+            "area_weight_g_m2": 495.395833,
+        }
         response = self.client.post(
             "/api/calculations/machine-max-product-length",
-            json={
-                "machine": "K7",
-                "core_diameter_mm": 133,
-                "thickness_mm": 4.311611,
-                "thickness_stddev_mm": 0.249999,
-                "product_width_m": 6,
-                "area_weight_g_m2": 495.395833,
-            },
+            json=payload,
             headers=self.headers,
         )
         result = response.get_json()
         self.assertEqual(response.status_code, 200)
         self.assertEqual(result["status"], "success")
+        self.assertEqual(result, calculate_machine_max_product_length(**payload))
+        self.assertIn("final_feasibility", result)
         self.assertEqual(
             result["production_maximums"]["nominal_governing_constraints"],
             ["roll_diameter_nominal"],
         )
 
+    def test_machine_maximum_length_endpoint_does_not_accept_mcp_article_convenience(self):
+        response = self.client.post(
+            "/api/calculations/machine-max-product-length",
+            json={
+                "article_number": "218500",
+                "machine": "K7",
+                "core_diameter_mm": 133,
+            },
+            headers=self.headers,
+        )
+
+        self.assertEqual(response.status_code, 200)
+        self.assertEqual(response.get_json(), {
+            "status": "invalid_parameter",
+            "invalid": [{
+                "field": "request",
+                "message": "unknown request fields: article_number",
+            }],
+        })
+
     def test_machine_maximum_length_endpoint_preserves_domain_outcomes(self):
         incompatible = self.client.post(
             "/api/calculations/machine-max-product-length",

tests/test_mcp_adapter.py

@@ -1,3 +1,4 @@
+import copy
 import inspect
 import sys
 import types
@@ -21,6 +22,7 @@ from rollcalc_mcp_tools import (
     calculate_roll_diameter_result,
     get_article_result,
     get_machine_result,
+    project_machine_max_product_length_result,
     search_articles_result,
 )
 from machine_constraints import (
@@ -103,7 +105,7 @@ class McpAdapterTests(unittest.TestCase):
             "feasible_with_warnings",
         )
 
-    def test_machine_maximum_length_adapter_delegates_to_shared_domain(self):
+    def test_machine_maximum_length_adapter_projects_success_without_mutating_domain(self):
         arguments = {
             "machine": "K7",
             "core_diameter_mm": 133.0,
@@ -112,10 +114,149 @@ class McpAdapterTests(unittest.TestCase):
             "product_width_m": 6.0,
             "area_weight_g_m2": 495.395833,
         }
-        self.assertEqual(
-            calculate_machine_max_product_length_result(**arguments),
-            calculate_machine_max_product_length(**arguments),
+        domain_result = calculate_machine_max_product_length(**arguments)
+        domain_before_projection = copy.deepcopy(domain_result)
+
+        self.assertNotIn(
+            "article_number",
+            inspect.signature(calculate_machine_max_product_length).parameters,
         )
+        result = project_machine_max_product_length_result(domain_result)
+
+        self.assertEqual(domain_result, domain_before_projection)
+        self.assertIn("final_feasibility", domain_result)
+        self.assertNotIn("final_feasibility", result)
+        self.assertEqual(
+            calculate_machine_max_product_length_result(**arguments), result
+        )
+        self.assertEqual(result["machine"], {"id": "k7", "name": "K7"})
+        self.assertEqual(result["weight_scope"], "material_only")
+        self.assertEqual(result["machine_limits"], {
+            "maximum_roll_diameter_mm": 1100.0,
+            "maximum_material_roll_weight_kg": 700.0,
+        })
+        self.assertEqual(result["production_maximums"], {
+            "nominal_length_m": 217.1900177447768,
+            "nominal_governing_constraints": ["roll_diameter_nominal"],
+            "conservative_length_m": 194.62073281485985,
+            "conservative_governing_constraints": ["roll_diameter_conservative"],
+        })
+        self.assertEqual(result["material_weights_kg"], {
+            "at_nominal_production_maximum": 645.570178559751,
+            "at_conservative_production_maximum": 578.4858003113276,
+        })
+        self.assertEqual(result["warnings"], {"nominal": ["roll_diameter_mm"]})
+
+    def test_machine_maximum_length_adapter_resolves_exact_article_compactly(self):
+        result = calculate_machine_max_product_length_result(
+            article_number="218500",
+            machine="K7",
+            core_diameter_mm=133.0,
+        )
+
+        self.assertEqual(result["status"], "success")
+        self.assertEqual(result["article"], {
+            "number": "218500",
+            "name": "Stex AS 501,      6,00 x 75 m",
+        })
+        self.assertNotIn("thickness_mm", result)
+        self.assertNotIn("final_feasibility", result)
+        self.assertEqual(result["production_maximums"], {
+            "nominal_length_m": 217.1900177447768,
+            "nominal_governing_constraints": ["roll_diameter_nominal"],
+            "conservative_length_m": 194.62073281485985,
+            "conservative_governing_constraints": ["roll_diameter_conservative"],
+        })
+        self.assertEqual(result["material_weights_kg"], {
+            "at_nominal_production_maximum": 645.570178559751,
+            "at_conservative_production_maximum": 578.4858003113276,
+        })
+
+    def test_machine_maximum_length_adapter_article_lookup_is_exact_and_core_is_caller_supplied(self):
+        missing = calculate_machine_max_product_length_result(
+            article_number="does-not-exist",
+            machine="K7",
+            core_diameter_mm=133.0,
+        )
+        incompatible_core = calculate_machine_max_product_length_result(
+            article_number="218500",
+            machine="K7",
+            core_diameter_mm=194.0,
+        )
+
+        self.assertEqual(missing, {
+            "status": "article_not_found",
+            "article_number": "does-not-exist",
+        })
+        self.assertEqual(incompatible_core["status"], "incompatible")
+        self.assertEqual(
+            incompatible_core["failed_compatibility_constraints"],
+            ["allowed_core_diameters_mm"],
+        )
+
+    def test_machine_maximum_length_adapter_rejects_mixed_article_and_material_inputs(self):
+        result = calculate_machine_max_product_length_result(
+            article_number="218500",
+            machine="K7",
+            core_diameter_mm=133.0,
+            thickness_mm=4.311611,
+        )
+
+        self.assertEqual(result, {
+            "status": "invalid_parameter",
+            "invalid": [{
+                "field": "article_number",
+                "message": (
+                    "cannot be combined with explicit material properties: "
+                    "thickness_mm"
+                ),
+            }],
+        })
+
+    def test_machine_maximum_length_adapter_preserves_non_success_diagnostics(self):
+        base = {
+            "machine": "K7",
+            "core_diameter_mm": 133.0,
+            "thickness_mm": 4.311611,
+            "thickness_stddev_mm": 0.249999,
+            "product_width_m": 6.0,
+            "area_weight_g_m2": 495.395833,
+        }
+        for changes, status in (
+            ({"core_diameter_mm": 194.0}, "incompatible"),
+            ({"product_width_m": 3.0}, "incompatible"),
+            (
+                {"product_width_m": None, "area_weight_g_m2": None},
+                "needs_clarification",
+            ),
+            ({"thickness_mm": -1.0}, "invalid_parameter"),
+            ({"machine": "not configured"}, "machine_not_found"),
+        ):
+            with self.subTest(changes=changes):
+                arguments = {**base, **changes}
+                domain_result = calculate_machine_max_product_length(**arguments)
+                adapter_result = calculate_machine_max_product_length_result(**arguments)
+                self.assertEqual(adapter_result, domain_result)
+                self.assertEqual(adapter_result["status"], status)
+
+        missing = calculate_machine_max_product_length_result(
+            **{**base, "product_width_m": None, "area_weight_g_m2": None}
+        )
+        self.assertEqual(
+            missing["missing_required_inputs"],
+            ["product_width_m", "area_weight_g_m2"],
+        )
+        core = calculate_machine_max_product_length_result(
+            **{**base, "core_diameter_mm": 194.0}
+        )
+        self.assertEqual(
+            core["failed_compatibility_constraints"],
+            ["allowed_core_diameters_mm"],
+        )
+        width = calculate_machine_max_product_length_result(
+            **{**base, "product_width_m": 3.0}
+        )
+        self.assertEqual(width["failed_compatibility_constraints"], ["product_width_m"])
 
     def test_material_weight_adapter_delegates_without_a_core_diameter(self):
         arguments = {
@@ -273,17 +414,19 @@ class McpAdapterTests(unittest.TestCase):
         self.assertIn("Missing configured V1 roll inputs", feasibility_tool.description)
         self.assertEqual(
             maximum_tool.parameters["required"],
-            ["machine", "core_diameter_mm", "thickness_mm"],
+            ["machine", "core_diameter_mm"],
         )
+        self.assertIn("article_number", maximum_tool.parameters["properties"])
         self.assertIn("product_width_m", maximum_tool.parameters["properties"])
         self.assertIn("area_weight_g_m2", maximum_tool.parameters["properties"])
         for text in (
-            "Resolve the article first with search_articles/get_article",
+            "exact article_number",
+            "do not call get_article merely to copy properties",
+            "Never mix article_number with material properties",
+            "For a product name, use search_articles",
+            "if candidates are multiple, ask the user to select an article number",
             "Do not supply or invent machine limits",
-            "rearrange roll or weight formulas",
-            "compare candidate limits yourself",
             "nominal and conservative/no-warning production maxima",
-            "incompatibility rather than substituting another core or width",
         ):
             self.assertIn(text, maximum_tool.description)
         self.assertEqual(