chore: import upstream snapshot with attribution

examples/stories/prompts/server.py

@@ -0,0 +1,43 @@
+"""Prompts primitive: register templates, list, render, complete an argument."""
+
+from mcp_types import Completion, CompletionArgument, CompletionContext, PromptReference, ResourceTemplateReference
+
+from mcp.server.mcpserver import MCPServer
+from mcp.server.mcpserver.prompts.base import AssistantMessage, Message, UserMessage
+from stories._hosting import run_server_from_args
+
+LANGUAGES = ["python", "pytorch", "rust", "go", "typescript"]
+
+
+def build_server() -> MCPServer:
+    mcp = MCPServer("prompts-example")
+
+    @mcp.prompt(title="Greeting")
+    def greet(name: str) -> str:
+        """Ask the model to greet someone by name."""
+        return f"Write a one-line greeting for {name}."
+
+    @mcp.prompt(title="Code Review")
+    def code_review(language: str, code: str) -> list[Message]:
+        """Ask the model to review a code snippet."""
+        return [
+            UserMessage(f"Review this {language} code for bugs and idioms:\n\n{code}"),
+            AssistantMessage("I'll review it. Let me read through the code first."),
+        ]
+
+    @mcp.completion()
+    async def complete(
+        ref: PromptReference | ResourceTemplateReference,
+        argument: CompletionArgument,
+        context: CompletionContext | None,
+    ) -> Completion | None:
+        if isinstance(ref, PromptReference) and ref.name == "code_review" and argument.name == "language":
+            matches = [lang for lang in LANGUAGES if lang.startswith(argument.value)]
+            return Completion(values=matches, total=len(matches), has_more=False)
+        return None
+
+    return mcp
+
+
+if __name__ == "__main__":
+    run_server_from_args(build_server)