Update server.js

server.js

@@ -136,9 +136,6 @@ class VertexAI {
         const contents = [];
 
         for (const message of messages) {
-            if (!message.role || !message.content) {
-                throw new Error("Each message must have role and content");
-            }
 
             let geminiRole;
             switch (message.role) {