feat(mcp): add support for completion specifications in MCP server

Add support for completion specifications in both sync and async MCP servers by:

- Adding parameters for SyncCompletionSpecification and AsyncCompletionSpecification
- Implementing registration of completion specifications in server builders
- Updating capabilities builders to include completions
- Upgrading MCP SDK version to 0.10.0-SNAPSHOT

Signed-off-by: Christian Tzolov <[email protected]>
Signed-off-by: minsoo.nam <[email protected]>

Author: tzolov

auto-configurations/mcp/spring-ai-autoconfigure-mcp-server/src/main/java/org/springframework/ai/mcp/server/autoconfigure/McpServerAutoConfiguration.java

@@ -28,9 +28,11 @@
 import io.modelcontextprotocol.server.McpServer.AsyncSpecification;
 import io.modelcontextprotocol.server.McpServer.SyncSpecification;
 import io.modelcontextprotocol.server.McpServerFeatures;
+import io.modelcontextprotocol.server.McpServerFeatures.AsyncCompletionSpecification;
 import io.modelcontextprotocol.server.McpServerFeatures.AsyncPromptSpecification;
 import io.modelcontextprotocol.server.McpServerFeatures.AsyncResourceSpecification;
 import io.modelcontextprotocol.server.McpServerFeatures.AsyncToolSpecification;
+import io.modelcontextprotocol.server.McpServerFeatures.SyncCompletionSpecification;
 import io.modelcontextprotocol.server.McpServerFeatures.SyncPromptSpecification;
 import io.modelcontextprotocol.server.McpServerFeatures.SyncResourceSpecification;
 import io.modelcontextprotocol.server.McpServerFeatures.SyncToolSpecification;
@@ -173,6 +175,7 @@ public McpSyncServer mcpSyncServer(McpServerTransportProvider transportProvider,
 			ObjectProvider<List<SyncToolSpecification>> tools,
 			ObjectProvider<List<SyncResourceSpecification>> resources,
 			ObjectProvider<List<SyncPromptSpecification>> prompts,
+			ObjectProvider<List<SyncCompletionSpecification>> completions,
 			ObjectProvider<BiConsumer<McpSyncServerExchange, List<McpSchema.Root>>> rootsChangeConsumers,
 			List<ToolCallbackProvider> toolCallbackProvider) {
 
@@ -216,6 +219,15 @@ public McpSyncServer mcpSyncServer(McpServerTransportProvider transportProvider,
 					+ serverProperties.isPromptChangeNotification());
 		}
 
+		List<SyncCompletionSpecification> completionSpecifications = completions.stream()
+			.flatMap(List::stream)
+			.toList();
+		if (!CollectionUtils.isEmpty(completionSpecifications)) {
+			serverBuilder.completions(completionSpecifications);
+			capabilitiesBuilder.completions();
+			logger.info("Registered completions: " + completionSpecifications.size());
+		}
+
 		rootsChangeConsumers.ifAvailable(consumer -> {
 			serverBuilder.rootsChangeHandler((exchange, roots) -> consumer.accept(exchange, roots));
 			logger.info("Registered roots change consumer");
@@ -270,6 +282,7 @@ public McpAsyncServer mcpAsyncServer(McpServerTransportProvider transportProvide
 			ObjectProvider<List<AsyncToolSpecification>> tools,
 			ObjectProvider<List<AsyncResourceSpecification>> resources,
 			ObjectProvider<List<AsyncPromptSpecification>> prompts,
+			ObjectProvider<List<AsyncCompletionSpecification>> completions,
 			ObjectProvider<BiConsumer<McpAsyncServerExchange, List<McpSchema.Root>>> rootsChangeConsumer,
 			List<ToolCallbackProvider> toolCallbackProvider) {
 
@@ -313,6 +326,15 @@ public McpAsyncServer mcpAsyncServer(McpServerTransportProvider transportProvide
 					+ serverProperties.isPromptChangeNotification());
 		}
 
+		List<AsyncCompletionSpecification> completionSpecifications = completions.stream()
+			.flatMap(List::stream)
+			.toList();
+		if (!CollectionUtils.isEmpty(completionSpecifications)) {
+			serverBuilder.completions(completionSpecifications);
+			capabilitiesBuilder.completions();
+			logger.info("Registered completions: " + completionSpecifications.size());
+		}
+
 		rootsChangeConsumer.ifAvailable(consumer -> {
 			BiFunction<McpAsyncServerExchange, List<McpSchema.Root>, Mono<Void>> asyncConsumer = (exchange, roots) -> {
 				consumer.accept(exchange, roots);

pom.xml

@@ -308,7 +308,7 @@
 		<okhttp3.version>4.12.0</okhttp3.version>
 
 		<!-- MCP-->
-		<mcp.sdk.version>0.9.0</mcp.sdk.version>
+		<mcp.sdk.version>0.10.0-SNAPSHOT</mcp.sdk.version>
 
 		<!-- plugin versions -->
 		<antlr.version>4.13.1</antlr.version>