fix: attribute merge optimization

Author: eeaters

mcp/src/main/java/io/modelcontextprotocol/client/McpAsyncClient.java

@@ -612,17 +612,17 @@ private McpSchema.ListToolsResult mergeToolsAnnotations(McpSchema.ListToolsResul
 		return new McpSchema.ListToolsResult(mergedTools, listToolsResult.nextCursor(), listToolsResult.meta());
 	}
 
-	private McpSchema.ToolAnnotations mergeAnnotations(McpSchema.ToolAnnotations original,
-			McpSchema.ToolAnnotations newer) {
-		if (original == null) {
-			return newer;
+	private McpSchema.ToolAnnotations mergeAnnotations(McpSchema.ToolAnnotations remoteAnnotations,
+			McpSchema.ToolAnnotations clientAnnotations) {
+		if (remoteAnnotations == null) {
+			return clientAnnotations;
 		}
-		return new McpSchema.ToolAnnotations(Utils.preferFirst(newer.title(), original.title()),
-				Utils.preferFirst(newer.readOnlyHint(), original.readOnlyHint()),
-				Utils.preferFirst(newer.destructiveHint(), original.destructiveHint()),
-				Utils.preferFirst(newer.idempotentHint(), original.idempotentHint()),
-				Utils.preferFirst(newer.openWorldHint(), original.openWorldHint()),
-				Utils.preferFirst(newer.returnDirect(), original.returnDirect()));
+		return new McpSchema.ToolAnnotations(Utils.preferFirst(clientAnnotations.title(), remoteAnnotations.title()),
+				Utils.mergeBoolean(clientAnnotations.readOnlyHint(), remoteAnnotations.readOnlyHint()),
+				Utils.mergeBoolean(clientAnnotations.destructiveHint(), remoteAnnotations.destructiveHint()),
+				Utils.mergeBoolean(clientAnnotations.idempotentHint(), remoteAnnotations.idempotentHint()),
+				Utils.mergeBoolean(clientAnnotations.openWorldHint(), remoteAnnotations.openWorldHint()),
+				Utils.mergeBoolean(clientAnnotations.returnDirect(), remoteAnnotations.returnDirect()));
 	}
 
 	private NotificationHandler asyncToolsChangeNotificationHandler(

mcp/src/main/java/io/modelcontextprotocol/util/Utils.java

@@ -117,4 +117,22 @@ public static <T> T preferFirst(T first, T second) {
 		return second != null ? second : first;
 	}
 
+
+	/**
+	 * Merges two boolean values. If the first value is null, the second value is returned.
+	 * If the second value is null, false is returned.
+	 * @param first The first boolean value
+	 * @param second The second boolean value
+	 * @return The merged boolean value
+	 */
+	public static Boolean mergeBoolean(Boolean first, Boolean second) {
+		if (first == null) {
+			return second;
+		}
+		if (second == null) {
+			return false;
+		}
+		return first && second;
+	}
+
 }