diff --git a/tools/shell/inc/shellInt.h b/tools/shell/inc/shellInt.h
index ba3dadc646..b1f09d5161 100644
--- a/tools/shell/inc/shellInt.h
+++ b/tools/shell/inc/shellInt.h
@@ -48,6 +48,7 @@
 #define SHELL_FLOAT_WIDTH                      20
 #define SHELL_DOUBLE_WIDTH                     25
 
+#define ERROR_CODE_DETAIL "\r\n\r\nTo view possible causes and suggested actions for error codes, see \r\n\"Error Code Reference\" in the TDengine online documentation.\r\n"
 typedef struct {
   char*   hist[SHELL_MAX_HISTORY_SIZE];
   char    file[TSDB_FILENAME_LEN];
diff --git a/tools/shell/src/shellAuto.c b/tools/shell/src/shellAuto.c
index 959e2d6d62..9fc929a595 100644
--- a/tools/shell/src/shellAuto.c
+++ b/tools/shell/src/shellAuto.c
@@ -662,6 +662,7 @@ void showHelp() {
     now - current time \n\
   Example : \n\
     select * from t1 where ts > now - 2w + 3d and ts <= now - 1w -2h ;\n");
+  printf(ERROR_CODE_DETAIL);
   printf("\n");
 }
 
diff --git a/tools/shell/src/shellEngine.c b/tools/shell/src/shellEngine.c
index 6d56aa7fe2..7328b67dff 100644
--- a/tools/shell/src/shellEngine.c
+++ b/tools/shell/src/shellEngine.c
@@ -1091,7 +1091,7 @@ void shellCleanupHistory() {
 
 void shellPrintError(TAOS_RES *tres, int64_t st) {
   int64_t et = taosGetTimestampUs();
-  fprintf(stderr, "\r\nDB error: %s (%.6fs)\r\n", taos_errstr(tres), (et - st) / 1E6);
+  fprintf(stderr, "\r\nDB error: %s[0x%08X] (%.6fs)\r\n", taos_errstr(tres), taos_errno(tres), (et - st) / 1E6);
   taos_free_result(tres);
 }
 
@@ -1303,6 +1303,8 @@ int32_t shellExecute() {
 #ifdef WEBSOCKET
   if (shell.args.restful || shell.args.cloud) {
     if (shell_conn_ws_server(1)) {
+      printf("failed to connect to server, reason: %s[0x%08X]\n%s", ws_errstr(NULL), ws_errno(NULL), ERROR_CODE_DETAIL);
+      fflush(stdout);
       return -1;
     }
   } else {
@@ -1314,7 +1316,7 @@ int32_t shellExecute() {
     }
 
     if (shell.conn == NULL) {
-      printf("failed to connect to server, reason: %s\n", taos_errstr(NULL));
+      printf("failed to connect to server, reason: %s[0x%08X]\n%s", taos_errstr(NULL), taos_errno(NULL), ERROR_CODE_DETAIL);
       fflush(stdout);
       return -1;
     }
diff --git a/tools/shell/src/shellWebsocket.c b/tools/shell/src/shellWebsocket.c
index 1ec1697c3a..61074102be 100644
--- a/tools/shell/src/shellWebsocket.c
+++ b/tools/shell/src/shellWebsocket.c
@@ -286,8 +286,8 @@ void shellRunSingleCommandWebsocketImp(char *command) {
       // if it's not a ws connection error
       if (TSDB_CODE_WS_DSN_ERROR != (code&TSDB_CODE_WS_DSN_ERROR)) {
         et = taosGetTimestampUs();
-        fprintf(stderr, "\nDB: error: %s (%.6fs)\n",
-                ws_errstr(res), (et - st)/1E6);
+        fprintf(stderr, "\nDB: error:0x%08X %s (%.6fs)\n",
+                ws_errno(res), ws_errstr(res), (et - st)/1E6);
         ws_free_result(res);
         return;
       }