docs: add a "What's new in v2" page (#3054)

docs_src/whats_new/tutorial001.py

@@ -0,0 +1,37 @@
+from mcp_types import (
+    INVALID_PARAMS,
+    CallToolRequestParams,
+    CallToolResult,
+    ListToolsResult,
+    PaginatedRequestParams,
+    TextContent,
+    Tool,
+)
+
+from mcp import MCPError
+from mcp.server import Server, ServerRequestContext
+
+SEARCH_BOOKS = Tool(
+    name="search_books",
+    description="Search the catalog by title or author.",
+    input_schema={  # (1)!
+        "type": "object",
+        "properties": {"query": {"type": "string"}},
+        "required": ["query"],
+    },
+)
+
+
+async def list_tools(ctx: ServerRequestContext, params: PaginatedRequestParams | None) -> ListToolsResult:  # (2)!
+    return ListToolsResult(tools=[SEARCH_BOOKS])  # (3)!
+
+
+async def call_tool(ctx: ServerRequestContext, params: CallToolRequestParams) -> CallToolResult:  # (4)!
+    if params.name != "search_books":
+        raise MCPError(INVALID_PARAMS, f"Unknown tool: {params.name}")  # (5)!
+    args = params.arguments or {}  # (6)!
+    text = f"Found 3 books matching {args['query']!r}."
+    return CallToolResult(content=[TextContent(type="text", text=text)])  # (7)!
+
+
+server = Server("Bookshop", on_list_tools=list_tools, on_call_tool=call_tool)  # (8)!