Extend resolver DI to sampling and roots requests (#3049)

docs_src/sampling_and_roots/tutorial002.py

@@ -0,0 +1,20 @@
+from typing import Annotated
+
+from mcp_types import ListRootsResult
+
+from mcp.server import MCPServer
+from mcp.server.mcpserver import ListRoots, Resolve
+
+mcp = MCPServer("Bookshop")
+
+
+def workspace_roots() -> ListRoots:
+    return ListRoots()
+
+
+@mcp.tool()
+async def catalog_folder(roots: Annotated[ListRootsResult, Resolve(workspace_roots)]) -> str:
+    """Pick the folder the catalog export should go to."""
+    if not roots.roots:
+        return "No workspace folders shared."
+    return str(roots.roots[0].uri)