"""Tests for MCP content conversion utilities.""" import base64 import json from typing import Annotated import pytest from arcade_core.catalog import MaterializedTool, ToolMeta, create_func_models from arcade_core.schema import ( InputParameter, ToolDefinition, ToolInput, ToolkitDefinition, ToolOutput, ToolRequirements, ValueSchema, ) from arcade_mcp_server import tool from arcade_mcp_server.convert import convert_to_mcp_content, create_mcp_tool # Small PNG header (1x1 transparent pixel) used for byte-image param tests PNG_BYTES = b"\x89PNG\r\n\x1a\n\x00\x00\x00\rIHDR\x00\x00\x00\x01\x00\x00\x00\x01\x08\x02\x00\x00\x00\x90wS\xde" class TestConvertToMCPContent: """Test convert_to_mcp_content function.""" @pytest.mark.parametrize( "value, expect_empty, decode_b64, expect_text", [ ("Hello, world!", False, False, "Hello, world!"), (42, False, False, "42"), (3.14159, False, False, "3.14159"), (1234567890, False, False, "1234567890"), (True, False, False, "True"), (False, False, False, "False"), ("single", False, False, None), # covers list wrapping behavior ("Hello\nWorld\tšŸŒ", False, False, "Hello\nWorld\tšŸŒ"), ("", False, False, ""), (b"Hello, binary world!", False, True, None), (PNG_BYTES, False, True, None), (None, True, False, None), ({}, False, False, "{}"), ([], False, False, "[]"), ], ) def test_convert_primitives_and_bytes(self, value, expect_empty, decode_b64, expect_text): """Parameterize primitives/bytes/empties/special cases.""" result = convert_to_mcp_content(value) if expect_empty: assert result == [] return assert isinstance(result, list) assert len(result) == 1 assert result[0].type == "text" text = result[0].text if decode_b64: decoded = base64.b64decode(text) assert decoded == value if expect_text is not None: assert text == expect_text @pytest.mark.parametrize( "data", [ {"name": "Alice", "age": 30, "active": True}, [1, 2, "three", {"four": 4}], { "users": [ {"id": 1, "name": "Alice", "tags": ["admin", "user"]}, {"id": 2, "name": "Bob", "tags": ["user"]}, ], "metadata": {"version": "1.0", "count": 2}, }, ], ) def test_convert_json_roundtrip(self, data): """Parameterize JSON-serializable structures and assert round-trip equality.""" result = convert_to_mcp_content(data) assert len(result) == 1 assert result[0].type == "text" parsed = json.loads(result[0].text) assert parsed == data def test_convert_circular_reference(self): """Test handling circular references in objects.""" # Create circular reference obj = {"a": 1} obj["self"] = obj # Should handle gracefully (implementation dependent) # Most JSON encoders will raise an error with pytest.raises(Exception): convert_to_mcp_content(obj) def test_convert_custom_objects(self): """Test converting custom objects.""" class CustomObject: def __str__(self): return "CustomObject instance" def __repr__(self): return "" obj = CustomObject() result = convert_to_mcp_content(obj) # Should use string representation assert "CustomObject" in result[0].text class TestCreateMCPTool: """Test create_mcp_tool function.""" @pytest.fixture def sample_tool_def(self): """Create a sample tool definition.""" return ToolDefinition( name="calculate", fully_qualified_name="MathToolkit.calculate", description="Perform a calculation", toolkit=ToolkitDefinition( name="MathToolkit", description="Math tools", version="1.0.0", ), input=ToolInput( parameters=[ InputParameter( name="expression", required=True, description="Math expression to evaluate", value_schema=ValueSchema(val_type="string"), ), InputParameter( name="precision", required=False, description="Decimal precision", value_schema=ValueSchema(val_type="integer"), ), ] ), output=ToolOutput( description="Calculation result", value_schema=ValueSchema(val_type="number"), ), requirements=ToolRequirements(), ) @pytest.fixture def materialized_tool(self, sample_tool_def): """Create a materialized tool.""" @tool def calculate( expression: Annotated[str, "Math expression"] = "1 + 1", precision: Annotated[int, "Decimal precision"] = 2, ) -> Annotated[float, "Calculation result"]: """Perform a calculation.""" return round(eval(expression), precision) # noqa: S307 input_model, output_model = create_func_models(calculate) meta = ToolMeta(module=calculate.__module__, toolkit=sample_tool_def.toolkit.name) return MaterializedTool( tool=calculate, definition=sample_tool_def, meta=meta, input_model=input_model, output_model=output_model, ) def test_create_basic_tool(self, materialized_tool): """Test creating basic MCP tool.""" mcp_tool = create_mcp_tool(materialized_tool) assert mcp_tool.name == "MathToolkit_calculate" # ensure input schema present assert isinstance(mcp_tool.inputSchema, dict) def test_tool_input_schema(self, materialized_tool): """Test tool input schema generation.""" mcp_tool = create_mcp_tool(materialized_tool) schema = mcp_tool.inputSchema assert schema["type"] == "object" assert "properties" in schema assert "expression" in schema["properties"] assert "precision" in schema["properties"] # Required may or may not be present depending on defaults if "required" in schema: assert "expression" in schema["required"] def _create_tool_def_with_type(self, param_type: str) -> ToolDefinition: return ToolDefinition( name="test", fully_qualified_name="Test.test", description="Test", toolkit=ToolkitDefinition(name="Test"), input=ToolInput( parameters=[ InputParameter( name="param", required=True, description="Test param", value_schema=ValueSchema(val_type=param_type), ) ] ), output=ToolOutput(), requirements=ToolRequirements(), ) @pytest.mark.parametrize( "arcade_type,json_type", [ ("string", "string"), ("integer", "integer"), ("number", "number"), ("boolean", "boolean"), ("array", "array"), ("json", "object"), ], ) def test_parameter_types(self, arcade_type, json_type): """Test different parameter type conversions (parameterized).""" tool_def = self._create_tool_def_with_type(arcade_type) @tool def f(param: Annotated[str, "Test param"]): return param input_model, output_model = create_func_models(f) meta = ToolMeta(module=f.__module__, toolkit=tool_def.toolkit.name) mat_tool = MaterializedTool( tool=f, definition=tool_def, meta=meta, input_model=input_model, output_model=output_model, ) mcp_tool = create_mcp_tool(mat_tool) param_schema = mcp_tool.inputSchema["properties"]["param"] assert param_schema["type"] == json_type def test_array_parameter(self): """Test array parameter with inner type.""" tool_def = ToolDefinition( name="test", fully_qualified_name="Test.test", description="Test", toolkit=ToolkitDefinition(name="Test"), input=ToolInput( parameters=[ InputParameter( name="items", required=True, description="List of items", value_schema=ValueSchema( val_type="array", inner_val_type="string", ), ) ] ), output=ToolOutput(), requirements=ToolRequirements(), ) @tool def f(items: Annotated[list[str], "List of items"]): return items input_model, output_model = create_func_models(f) meta = ToolMeta(module=f.__module__, toolkit=tool_def.toolkit.name) mat_tool = MaterializedTool( tool=f, definition=tool_def, meta=meta, input_model=input_model, output_model=output_model, ) mcp_tool = create_mcp_tool(mat_tool) param_schema = mcp_tool.inputSchema["properties"]["items"] assert param_schema["type"] == "array" assert param_schema["items"]["type"] == "string" def test_enum_parameter(self): """Test enum parameter values.""" tool_def = ToolDefinition( name="test", fully_qualified_name="Test.test", description="Test", toolkit=ToolkitDefinition(name="Test"), input=ToolInput( parameters=[ InputParameter( name="color", required=True, description="Color choice", value_schema=ValueSchema( val_type="string", enum=["red", "green", "blue"], ), ) ] ), output=ToolOutput(), requirements=ToolRequirements(), ) @tool def f(color: Annotated[str, "Color choice"]): return color input_model, output_model = create_func_models(f) meta = ToolMeta(module=f.__module__, toolkit=tool_def.toolkit.name) mat_tool = MaterializedTool( tool=f, definition=tool_def, meta=meta, input_model=input_model, output_model=output_model, ) mcp_tool = create_mcp_tool(mat_tool) param_schema = mcp_tool.inputSchema["properties"]["color"] assert param_schema["type"] == "string" assert param_schema["enum"] == ["red", "green", "blue"] def test_no_parameters(self): """Test tool with no parameters.""" tool_def = ToolDefinition( name="test", fully_qualified_name="Test.test", description="Test", toolkit=ToolkitDefinition(name="Test"), input=ToolInput(parameters=[]), output=ToolOutput(), requirements=ToolRequirements(), ) @tool def f() -> Annotated[str, "result"]: return "result" input_model, output_model = create_func_models(f) meta = ToolMeta(module=f.__module__, toolkit=tool_def.toolkit.name) mat_tool = MaterializedTool( tool=f, definition=tool_def, meta=meta, input_model=input_model, output_model=output_model, ) mcp_tool = create_mcp_tool(mat_tool) schema = mcp_tool.inputSchema assert schema["type"] == "object" assert schema["properties"] == {} assert schema.get("required", []) in ([], None) def test_output_schema_included(self, materialized_tool): """Test that output schema is included when definition has one.""" mcp_tool = create_mcp_tool(materialized_tool) # The fixture's output has value_schema=ValueSchema(val_type="number") assert mcp_tool.outputSchema is not None assert mcp_tool.outputSchema["type"] == "number"