Add story-style examples suite (27 stories + harness + CI) (#2957)

examples/stories/custom_methods/server.py

@@ -0,0 +1,39 @@
+"""Register a vendor-prefixed JSON-RPC method on the low-level Server.
+
+`MCPServer` has no public surface for arbitrary method registration, so this
+story's `server.py` is lowlevel-native (no `server_lowlevel.py` sibling).
+"""
+
+from typing import Any
+
+import mcp_types as types
+
+from mcp.server.context import ServerRequestContext
+from mcp.server.lowlevel import Server
+from stories._hosting import run_server_from_args
+
+
+class SearchParams(types.RequestParams):
+    """Subclass `RequestParams` so `_meta` (and the 2026 envelope keys) parse uniformly."""
+
+    query: str
+    limit: int = 10
+
+
+class SearchResult(types.Result):
+    items: list[str]
+
+
+def build_server() -> Server[Any]:
+    server = Server("custom-methods-example")
+
+    async def search(ctx: ServerRequestContext[Any], params: SearchParams) -> SearchResult:
+        items = [f"{params.query}-{i}" for i in range(params.limit)]
+        return SearchResult(items=items)
+
+    server.add_request_handler("acme/search", SearchParams, search)
+    return server
+
+
+if __name__ == "__main__":
+    run_server_from_args(build_server)