Simple HTTP MCP Server

from http import HTTPStatus from starlette.testclient import TestClient from http_mcp.server import MCPServer from http_mcp.types import Arguments, Tool from tests.models import TestToolArguments, TestToolOutput async def simple_server_tool(args: Arguments[TestToolArguments]) -> TestToolOutput: """Return a simple server tool.""" assert args.inputs.question == "What is the meaning of life?" assert args.request.method == "POST" return TestToolOutput(answer=f"Hello, {args.inputs.question}!") TOOLS_SIMPLE_SERVER = ( Tool( func=simple_server_tool, inputs=TestToolArguments, output=TestToolOutput, ), ) def test_server_list_tools() -> None: server = MCPServer(tools=TOOLS_SIMPLE_SERVER, name="test", version="1.0.0") client = TestClient(server.app) response = client.post("/mcp", json={"jsonrpc": "2.0", "method": "tools/list", "id": 1}) assert response.status_code == HTTPStatus.OK response_json = response.json() assert response_json == { "jsonrpc": "2.0", "id": 1, "result": { "tools": [ { "name": "simple_server_tool", "title": "Simple Server Tool", "description": "Return a simple server tool.", "inputSchema": { "title": "simple_server_toolArguments", "type": "object", "properties": {"question": {"title": "Question", "type": "string"}}, "required": ["question"], }, "outputSchema": { "title": "simple_server_toolOutput", "type": "object", "properties": {"answer": {"title": "Answer", "type": "string"}}, "required": ["answer"], }, "annotations": { "title": "Simple Server Tool", "readOnlyHint": False, "destructiveHint": False, "idempotentHint": True, "openWorldHint": True, }, "meta": None, }, ], "nextCursor": "", }, } def test_server_call_tool() -> None: server = MCPServer(tools=TOOLS_SIMPLE_SERVER, name="test", version="1.0.0") client = TestClient(server.app) response = client.post( "/mcp", json={ "jsonrpc": "2.0", "method": "tools/call", "id": 1, "params": { "name": "simple_server_tool", "arguments": {"question": "What is the meaning of life?"}, }, }, ) assert response.status_code == HTTPStatus.OK response_json = response.json() assert response_json == { "jsonrpc": "2.0", "id": 1, "result": { "content": [ { "type": "text", "text": '{"answer":"Hello, What is the meaning of life?!"}', }, ], "structuredContent": {"answer": "Hello, What is the meaning of life?!"}, "isError": False, }, }