test tool_call

Author: narumiruna

src/mcpservertemplate/server.py

@@ -13,7 +13,7 @@ def add_numbers(
     b: Annotated[float, Field(description="The second number")],
 ) -> str:
     """Add two numbers and return the result as a string."""
-    return f"{a} + {b} = {a+b} from MCP Template"
+    return str(a + b)
 
 
 def main():

tests/test_server.py

@@ -2,6 +2,9 @@
 from mcp import ClientSession
 from mcp import StdioServerParameters
 from mcp import stdio_client
+from mcp.types import TextContent
+
+from mcpservertemplate.server import add_numbers
 
 
 @pytest.fixture
@@ -16,3 +19,17 @@ async def test_list_tools(server_params: StdioServerParameters) -> None:
 
         result = await session.list_tools()
         assert len(result.tools) > 0
+
+
+@pytest.mark.asyncio
+async def test_call_tool(server_params: StdioServerParameters) -> None:
+    async with stdio_client(server_params) as (read, write), ClientSession(read, write) as session:
+        await session.initialize()
+
+        a = 1234
+        b = 5678
+        result = await session.call_tool("add_numbers", {"a": a, "b": b})
+
+        assert len(result.content) == 1
+        assert isinstance(result.content[0], TextContent)
+        assert float(result.content[0].text) == a + b