feat(server): support sync stateless primitive repositories

Author: ultramancode

mcp-core/src/main/java/io/modelcontextprotocol/server/CompletionsRepository.java

@@ -0,0 +1,26 @@
+/*
+ * Copyright 2024-2026 the original author or authors.
+ */
+
+package io.modelcontextprotocol.server;
+
+import io.modelcontextprotocol.common.McpTransportContext;
+import io.modelcontextprotocol.spec.McpSchema;
+
+/**
+ * Repository contract for handling stateless completion requests from the current MCP
+ * request context.
+ *
+ * @author Taewoong Kim
+ */
+public interface CompletionsRepository {
+
+	/**
+	 * Complete the request for the current request context.
+	 * @param request the completion request
+	 * @param transportContext the transport context for the current request
+	 * @return the completion result
+	 */
+	McpSchema.CompleteResult complete(McpSchema.CompleteRequest request, McpTransportContext transportContext);
+
+}