Add docs and message field for ProgressNotification

Author: 134130

mcp/src/main/java/io/modelcontextprotocol/spec/McpSchema.java

@@ -21,6 +21,7 @@
 import io.modelcontextprotocol.util.Assert;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import reactor.util.annotation.Nullable;
 
 /**
  * Based on the <a href="http://www.jsonrpc.org/specification">JSON-RPC 2.0
@@ -755,10 +756,15 @@ private static JsonSchema parseSchema(String schema) {
 	@JsonIgnoreProperties(ignoreUnknown = true)
 	public record CallToolRequest(// @formatter:off
 		@JsonProperty("name") String name,
-		@JsonProperty("arguments") Map<String, Object> arguments) implements Request {
+		@JsonProperty("arguments") Map<String, Object> arguments,
+		@Nullable @JsonProperty("_meta") Map<String, Object> _meta) implements Request {
 
 		public CallToolRequest(String name, String jsonArguments) {
-			this(name, parseJsonArguments(jsonArguments));			
+			this(name, parseJsonArguments(jsonArguments), null);
+		}
+
+		public CallToolRequest(String name, Map<String, Object> arguments) {
+			this(name, arguments, null);
 		}
 
 		private static Map<String, Object> parseJsonArguments(String jsonArguments) {
@@ -1104,11 +1110,23 @@ public record PaginatedResult(@JsonProperty("nextCursor") String nextCursor) {
 	// ---------------------------
 	// Progress and Logging
 	// ---------------------------
+
+	/**
+	 * The Model Context Protocol (MCP) supports optional progress tracking for long-running
+	 * operations through notification messages. Either side can send progress notifications
+	 * to provide updates about operation status.
+	 *
+	 * @param progressToken The original progress token
+	 * @param progress The current progress value so far
+	 * @param total An optional “total” value
+	 * @param message An optional “message” value
+	 */
 	@JsonIgnoreProperties(ignoreUnknown = true)
 	public record ProgressNotification(// @formatter:off
 		@JsonProperty("progressToken") String progressToken,
-		@JsonProperty("progress") double progress,
-		@JsonProperty("total") Double total) {
+		@JsonProperty("progress") Double progress,
+		@JsonProperty("total") Double total,
+	    @JsonProperty("message") String message) {
 	}// @formatter:on
 
 	/**