fix: Correct MCP inputSchema generation and bump version to 0.3.0

Author: crowecawcaw

click_mcp/__init__.py

@@ -4,5 +4,5 @@
 
 from .decorator import click_mcp
 
-__version__ = "0.2.0"
+__version__ = "0.3.0"
 __all__ = ["click_mcp", "__version__"]

click_mcp/scanner.py

@@ -60,18 +60,30 @@ def _convert_command_info_to_tool(
     """Convert a Click command info dict to an MCP tool."""
     description = command_info.get("help") or command_info.get("short_help") or ""
 
-    parameters: Dict[str, Dict[str, Any]] = {}
+    properties: Dict[str, Dict[str, Any]] = {}
+    required_params: List[str] = []
+
     for param_info in command_info.get("params", []):
         param_name = param_info.get("name")
         if param_name:
             param_data = _get_parameter_info_from_dict(param_info)
             if param_data:
-                parameters[param_name] = param_data
+                properties[param_name] = param_data
+                if param_data.get("required", False):
+                    required_params.append(param_name)
+
+    # Construct the final input schema according to JSON Schema / MCP spec
+    input_schema: Dict[str, Any] = {
+        "type": "object",
+        "properties": properties,
+    }
+    if required_params:
+        input_schema["required"] = sorted(required_params)  # Sort for consistent output
 
     return types.Tool(
         name=name,
         description=description,
-        inputSchema=parameters,
+        inputSchema=input_schema,
     )
 
 
@@ -99,12 +111,15 @@ def _get_parameter_info_from_dict(
     if "choices" in param_info:
         schema["enum"] = param_info["choices"]
 
-    # Create parameter info
+    # Create parameter info (this represents the schema for a single property)
     param_data = {
         "description": param_info.get("help", ""),
-        "required": param_info.get("required", False),
         "schema": schema,
     }
+    # Add 'required' flag separately for collecting at the top level
+    is_required = param_info.get("required", False)
+    if is_required:
+        param_data["required"] = True  # Keep track for the loop above
 
     # Add default if available and not callable
     default = param_info.get("default")

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "click-mcp"
-version = "0.2.0"
+version = "0.3.0"
 description = "Extend Click applications with Model Context Protocol (MCP) support"
 readme = "README.md"
 authors = [
@@ -34,9 +34,6 @@ Issues = "https://github.com/crowecawcaw/click-mcp/issues"
 [tool.hatch.build.targets.wheel]
 packages = ["click_mcp"]
 
-[tool.hatch.version]
-path = "click_mcp/_version.py"
-
 [tool.black]
 target-version = ['py310', 'py311', 'py312', 'py313']
 line-length = 88

tests/test_mcp_server.py

@@ -67,8 +67,13 @@ async def test_basic_server_tools(basic_mcp_session):
             break
 
     assert greet_tool is not None
-    assert "name" in greet_tool.inputSchema
-    assert greet_tool.inputSchema["name"]["required"] is True
+    # Verify inputSchema structure
+    assert greet_tool.inputSchema["type"] == "object"
+    assert "properties" in greet_tool.inputSchema
+    assert "name" in greet_tool.inputSchema["properties"]
+    assert greet_tool.inputSchema["properties"]["name"]["required"] is True
+    assert "required" in greet_tool.inputSchema
+    assert "name" in greet_tool.inputSchema["required"]
 
     # Find the users.list command
     users_list_tool = None
@@ -78,6 +83,14 @@ async def test_basic_server_tools(basic_mcp_session):
             break
 
     assert users_list_tool is not None
+    # Verify inputSchema structure (should only have help param)
+    assert users_list_tool.inputSchema["type"] == "object"
+    assert "properties" in users_list_tool.inputSchema
+    # Click automatically adds --help, so we expect only that property
+    assert len(users_list_tool.inputSchema["properties"]) <= 1
+    if len(users_list_tool.inputSchema["properties"]) == 1:
+        assert "help" in users_list_tool.inputSchema["properties"]
+    assert "required" not in users_list_tool.inputSchema  # No required params
 
     # Find the echo command
     echo_tool = None
@@ -87,9 +100,14 @@ async def test_basic_server_tools(basic_mcp_session):
             break
 
     assert echo_tool is not None
-    assert "count" in echo_tool.inputSchema
-    assert echo_tool.inputSchema["count"]["schema"]["type"] == "integer"
-    assert "message" in echo_tool.inputSchema
+    # Verify inputSchema structure
+    assert echo_tool.inputSchema["type"] == "object"
+    assert "properties" in echo_tool.inputSchema
+    assert "count" in echo_tool.inputSchema["properties"]
+    assert echo_tool.inputSchema["properties"]["count"]["schema"]["type"] == "integer"
+    assert "message" in echo_tool.inputSchema["properties"]
+    assert "required" in echo_tool.inputSchema
+    assert "message" in echo_tool.inputSchema["required"]  # Only message is required
 
 
 @pytest.mark.anyio
@@ -234,8 +252,14 @@ async def test_advanced_server_tools(advanced_mcp_session):
             break
 
     assert config_set_tool is not None
-    assert "key" in config_set_tool.inputSchema
-    assert "value" in config_set_tool.inputSchema
+    # Verify inputSchema structure
+    assert config_set_tool.inputSchema["type"] == "object"
+    assert "properties" in config_set_tool.inputSchema
+    assert "key" in config_set_tool.inputSchema["properties"]
+    assert "value" in config_set_tool.inputSchema["properties"]
+    assert "required" in config_set_tool.inputSchema
+    assert "key" in config_set_tool.inputSchema["required"]
+    assert "value" in config_set_tool.inputSchema["required"]
 
     # Find the greet command with formal option
     greet_tool = None
@@ -245,8 +269,14 @@ async def test_advanced_server_tools(advanced_mcp_session):
             break
 
     assert greet_tool is not None
-    assert "formal" in greet_tool.inputSchema
-    assert greet_tool.inputSchema["formal"]["schema"]["type"] == "boolean"
+    # Verify inputSchema structure
+    assert greet_tool.inputSchema["type"] == "object"
+    assert "properties" in greet_tool.inputSchema
+    assert "name" in greet_tool.inputSchema["properties"]
+    assert "formal" in greet_tool.inputSchema["properties"]
+    assert greet_tool.inputSchema["properties"]["formal"]["schema"]["type"] == "boolean"
+    assert "required" in greet_tool.inputSchema
+    assert "name" in greet_tool.inputSchema["required"]  # Only name is required
 
 
 @pytest.fixture