diff --git a/application/src/main/java/org/thingsboard/server/service/script/RuleNodeTbelScriptEngine.java b/application/src/main/java/org/thingsboard/server/service/script/RuleNodeTbelScriptEngine.java
index 2b1734b197..08b2d5e245 100644
--- a/application/src/main/java/org/thingsboard/server/service/script/RuleNodeTbelScriptEngine.java
+++ b/application/src/main/java/org/thingsboard/server/service/script/RuleNodeTbelScriptEngine.java
@@ -64,7 +64,7 @@ public class RuleNodeTbelScriptEngine extends RuleNodeScriptEngine<TbelInvokeSer
             List<TbMsg> res = new ArrayList<>();
             for (Object resObject : (Collection) result) {
                 if (resObject instanceof Map) {
-                    res.add(unbindMsg((Map) result, msg));
+                    res.add(unbindMsg((Map) resObject, msg));
                 } else {
                     return wrongResultType(resObject);
                 }
diff --git a/ui-ngx/src/assets/help/en_US/rulenode/clear_alarm_node_script_fn.md b/ui-ngx/src/assets/help/en_US/rulenode/clear_alarm_node_script_fn.md
index 74e4c83828..eed5cb2f07 100644
--- a/ui-ngx/src/assets/help/en_US/rulenode/clear_alarm_node_script_fn.md
+++ b/ui-ngx/src/assets/help/en_US/rulenode/clear_alarm_node_script_fn.md
@@ -22,9 +22,10 @@ Current Alarm Details can be accessed via `metadata.prevAlarmDetails`.<br>
 ```javascript
 var details = {};
 if (metadata.prevAlarmDetails) {
+  details = JSON.parse(metadata.prevAlarmDetails);
   // remove prevAlarmDetails from metadata
   delete metadata.prevAlarmDetails;
-  details = JSON.parse(metadata.prevAlarmDetails);
+  //now metadata is the same as it comes IN this rule node
 }
 {:copy-code}
 ```
diff --git a/ui-ngx/src/assets/help/en_US/rulenode/create_alarm_node_script_fn.md b/ui-ngx/src/assets/help/en_US/rulenode/create_alarm_node_script_fn.md
index c6c2fe2481..36bdd21d16 100644
--- a/ui-ngx/src/assets/help/en_US/rulenode/create_alarm_node_script_fn.md
+++ b/ui-ngx/src/assets/help/en_US/rulenode/create_alarm_node_script_fn.md
@@ -22,10 +22,11 @@ is a raw String field, and it needs to be converted into object using this const
 
 ```javascript
 var details = {};
-if (metadata.prevAlarmDetails) {
-  // remove prevAlarmDetails from metadata
-  delete metadata.prevAlarmDetails;
+if (metadata.prevAlarmDetails != null) {
   details = JSON.parse(metadata.prevAlarmDetails);
+  // remove prevAlarmDetails from metadata
+  metadata.remove('prevAlarmDetails');
+  //now metadata is the same as it comes IN this rule node
 }
 {:copy-code}
 ```
@@ -44,11 +45,11 @@ Also put <code>temperature</code> attribute from inbound Message payload into Al
 ```javascript
 var details = {temperature: msg.temperature, count: 1};
 
-if (metadata.prevAlarmDetails) {
+if (metadata.prevAlarmDetails != null) {
   var prevDetails = JSON.parse(metadata.prevAlarmDetails);
   // remove prevAlarmDetails from metadata
-  delete metadata.prevAlarmDetails;
-  if (prevDetails.count) {
+  metadata.remove('prevAlarmDetails');
+  if (prevDetails.count != null) {
     details.count = prevDetails.count + 1;
   }
 }
diff --git a/ui-ngx/src/assets/help/en_US/rulenode/tbel/clear_alarm_node_script_fn.md b/ui-ngx/src/assets/help/en_US/rulenode/tbel/clear_alarm_node_script_fn.md
index 2acf8b7041..311086e785 100644
--- a/ui-ngx/src/assets/help/en_US/rulenode/tbel/clear_alarm_node_script_fn.md
+++ b/ui-ngx/src/assets/help/en_US/rulenode/tbel/clear_alarm_node_script_fn.md
@@ -5,7 +5,7 @@
 
 *function Details(msg, metadata, msgType): any*
 
-JavaScript function generating **Alarm Details** object to update existing one. Used for storing additional parameters inside Alarm.<br>
+[TBEL{:target="_blank"}](${siteBaseUrl}/docs/user-guide/tbel/) function generating **Alarm Details** object to update existing one. Used for storing additional parameters inside Alarm.<br>
 For example you can save attribute name/value pair from Original Message payload or Metadata.
 
 **Parameters:**
@@ -21,10 +21,11 @@ Current Alarm Details can be accessed via `metadata.prevAlarmDetails`.<br>
 
 ```javascript
 var details = {};
-if (metadata.prevAlarmDetails) {
-  // remove prevAlarmDetails from metadata
-  delete metadata.prevAlarmDetails;
+if (metadata.prevAlarmDetails != null) {
   details = JSON.parse(metadata.prevAlarmDetails);
+  // remove prevAlarmDetails from metadata
+  metadata.remove('prevAlarmDetails');
+  //now metadata is the same as it comes IN this rule node
 }
 {:copy-code}
 ```
@@ -43,11 +44,11 @@ Also put <code>temperature</code> attribute from inbound Message payload into Al
 ```javascript
 var details = {temperature: msg.temperature, count: 1};
 
-if (metadata.prevAlarmDetails) {
+if (metadata.prevAlarmDetails != null) {
   var prevDetails = JSON.parse(metadata.prevAlarmDetails);
   // remove prevAlarmDetails from metadata
-  delete metadata.prevAlarmDetails;
-  if (prevDetails.count) {
+  metadata.remove('prevAlarmDetails');
+  if (prevDetails.count != null) {
     details.count = prevDetails.count + 1;
   }
 }
diff --git a/ui-ngx/src/assets/help/en_US/rulenode/tbel/create_alarm_node_script_fn.md b/ui-ngx/src/assets/help/en_US/rulenode/tbel/create_alarm_node_script_fn.md
index 6bf6a23239..afc9051590 100644
--- a/ui-ngx/src/assets/help/en_US/rulenode/tbel/create_alarm_node_script_fn.md
+++ b/ui-ngx/src/assets/help/en_US/rulenode/tbel/create_alarm_node_script_fn.md
@@ -5,7 +5,7 @@
 
 *function Details(msg, metadata, msgType): any*
 
-JavaScript function generating **Alarm Details** object. Used for storing additional parameters inside Alarm.<br>
+[TBEL{:target="_blank"}](${siteBaseUrl}/docs/user-guide/tbel/) function generating **Alarm Details** object. Used for storing additional parameters inside Alarm.<br>
 For example you can save attribute name/value pair from Original Message payload or Metadata.
 
 **Parameters:**
diff --git a/ui-ngx/src/assets/help/en_US/rulenode/tbel/filter_node_script_fn.md b/ui-ngx/src/assets/help/en_US/rulenode/tbel/filter_node_script_fn.md
index 1a64a2d119..4435acaeff 100644
--- a/ui-ngx/src/assets/help/en_US/rulenode/tbel/filter_node_script_fn.md
+++ b/ui-ngx/src/assets/help/en_US/rulenode/tbel/filter_node_script_fn.md
@@ -5,7 +5,7 @@
 
 *function Filter(msg, metadata, msgType): boolean*
 
-JavaScript function defines a boolean expression based on the incoming Message and Metadata.
+[TBEL{:target="_blank"}](${siteBaseUrl}/docs/user-guide/tbel/) function defines a boolean expression based on the incoming Message and Metadata.
 
 **Parameters:**
 
@@ -37,14 +37,14 @@ Example of the rule chain configuration:
 * Same as above, but checks that the message has 'temperature' field to **avoid failures** on unexpected messages:
 
 ```javascript
-return typeof msg.temperature !== 'undefined' && msg.temperature > 20;
+return msg.temperature != null && msg.temperature > 20;
 {:copy-code}
 ```
 
 * Forward all messages with type `ATTRIBUTES_UPDATED` to the **True** chain and all other messages to the **False** chain:
 
 ```javascript
-if (msgType === 'ATTRIBUTES_UPDATED') {
+if (msgType == 'ATTRIBUTES_UPDATED') {
     return true;
 } else {
     return false;
@@ -61,10 +61,10 @@ Otherwise send message to the <strong>False</strong> chain:
 </ul>
 
 ```javascript
-if (msgType === 'POST_TELEMETRY_REQUEST') {
-  if (metadata.deviceType === 'vehicle') {
+if (msgType == 'POST_TELEMETRY_REQUEST') {
+  if (metadata.deviceType == 'vehicle') {
     return msg.humidity > 50;
-  } else if (metadata.deviceType === 'controller') {
+  } else if (metadata.deviceType == 'controller') {
     return msg.temperature > 20 && msg.humidity > 60;
   }
 }
diff --git a/ui-ngx/src/assets/help/en_US/rulenode/tbel/generator_node_script_fn.md b/ui-ngx/src/assets/help/en_US/rulenode/tbel/generator_node_script_fn.md
index ac8b6abf56..7618ac4090 100644
--- a/ui-ngx/src/assets/help/en_US/rulenode/tbel/generator_node_script_fn.md
+++ b/ui-ngx/src/assets/help/en_US/rulenode/tbel/generator_node_script_fn.md
@@ -5,7 +5,7 @@
 
 *function Generate(prevMsg, prevMetadata, prevMsgType): {msg: object, metadata: object, msgType: string}*
 
-JavaScript function generating new Message using previous Message payload, Metadata and Message type as input arguments.
+[TBEL{:target="_blank"}](${siteBaseUrl}/docs/user-guide/tbel/) function generating new Message using previous Message payload, Metadata and Message type as input arguments.
 
 **Parameters:**
 
@@ -78,16 +78,14 @@ var temperature = lower;
 
 // Get previous values
 
-if (typeof prevMetadata !== 'undefined' &&
-  typeof prevMetadata.isDecrement !== 'undefined') {
+if (prevMetadata != null && prevMetadata.isDecrement != null) {
   isDecrement = prevMetadata.isDecrement;
 }
-if (typeof prevMsg !== 'undefined' &&
-  typeof prevMsg.temperature !== 'undefined') {
+if (prevMsg != null && prevMsg.temperature != null) {
   temperature = prevMsg.temperature;
 }
 
-if (isDecrement === 'true') {
+if (isDecrement == 'true') {
   temperature--;
   if (temperature <= lower) {
     isDecrement = 'false';
diff --git a/ui-ngx/src/assets/help/en_US/rulenode/tbel/log_node_script_fn.md b/ui-ngx/src/assets/help/en_US/rulenode/tbel/log_node_script_fn.md
index 402de1955e..bab38ad46f 100644
--- a/ui-ngx/src/assets/help/en_US/rulenode/tbel/log_node_script_fn.md
+++ b/ui-ngx/src/assets/help/en_US/rulenode/tbel/log_node_script_fn.md
@@ -5,7 +5,7 @@
 
 *function toString(msg, metadata, msgType): string*
 
-JavaScript function transforming incoming Message to String for further logging to the server log file.
+[TBEL{:target="_blank"}](${siteBaseUrl}/docs/user-guide/tbel/) function transforming incoming Message to String for further logging to the server log file.
 
 **Parameters:**
 
diff --git a/ui-ngx/src/assets/help/en_US/rulenode/tbel/switch_node_script_fn.md b/ui-ngx/src/assets/help/en_US/rulenode/tbel/switch_node_script_fn.md
index 7e8d964059..7fd3b7447b 100644
--- a/ui-ngx/src/assets/help/en_US/rulenode/tbel/switch_node_script_fn.md
+++ b/ui-ngx/src/assets/help/en_US/rulenode/tbel/switch_node_script_fn.md
@@ -5,7 +5,7 @@
 
 *function Switch(msg, metadata, msgType): string[]*
 
-JavaScript function computing **an array of Link names** to forward the incoming Message.
+[TBEL{:target="_blank"}](${siteBaseUrl}/docs/user-guide/tbel/) function computing **an array of Link names** to forward the incoming Message.
 
 **Parameters:**
 
@@ -72,16 +72,16 @@ Example of the rule chain configuration:
 </ul>
 
 ```javascript
-if (msgType === 'POST_TELEMETRY_REQUEST') {
+if (msgType == 'POST_TELEMETRY_REQUEST') {
   if (msg.temperature < 18) {
     return ['Low Temperature Telemetry'];
   } else {
     return ['Normal Temperature Telemetry'];
   }
-} else if (msgType === 'POST_ATTRIBUTES_REQUEST') {
-  if (msg.currentState === 'IDLE') {
+} else if (msgType == 'POST_ATTRIBUTES_REQUEST') {
+  if (msg.currentState == 'IDLE') {
     return ['Idle State', 'Update State Attribute'];
-  } else if (msg.currentState === 'RUNNING') {
+  } else if (msg.currentState == 'RUNNING') {
     return ['Running State', 'Update State Attribute'];
   } else {
     return ['Unknown State'];
diff --git a/ui-ngx/src/assets/help/en_US/rulenode/tbel/transformation_node_script_fn.md b/ui-ngx/src/assets/help/en_US/rulenode/tbel/transformation_node_script_fn.md
index eb28bbe6d6..44ada19967 100644
--- a/ui-ngx/src/assets/help/en_US/rulenode/tbel/transformation_node_script_fn.md
+++ b/ui-ngx/src/assets/help/en_US/rulenode/tbel/transformation_node_script_fn.md
@@ -5,7 +5,7 @@
 
 *function Transform(msg, metadata, msgType): {msg: object, metadata: object, msgType: string}*
 
-The JavaScript function to transform input Message payload, Metadata and/or Message type to the output message.  
+The [TBEL{:target="_blank"}](${siteBaseUrl}/docs/user-guide/tbel/) function to transform input Message payload, Metadata and/or Message type to the output message.  
 
 **Parameters:**
 
@@ -32,7 +32,7 @@ All fields in resulting object are optional and will be taken from original mess
 * Add sum of two fields ('a' and 'b') as a new field ('sum') of existing message:
 
 ```javascript
-if(typeof msg.a !== "undefined" && typeof msg.b !== "undefined"){
+if(msg.a != null && msg.b != null){
     msg.sum = msg.a + msg.b;
 }
 return {msg: msg};
@@ -41,7 +41,7 @@ return {msg: msg};
 * Transform value of the 'temperature' field from °F to °C:
 
 ```javascript
-msg.temperature = (msg.temperature - 32) * 5 / 9;
+msg.temperature = toFixed((msg.temperature - 32) * 5 / 9, 1);
 return {msg: msg};
 ```
 
@@ -49,7 +49,7 @@ return {msg: msg};
 
 ```javascript
 var newMsg = {
-    count: Object.keys(msg).length
+    count: msg.size()
 };
 return {msg: newMsg};
 ```
@@ -73,9 +73,9 @@ var sum = msg.a + msg.b;
 var diff = msg.a - msg.b;
 
 return [
-    {msg: {sum: sum}, metadata: metadata, msgType: msgType},
-    {msg: {difference: diff}, metadata: metadata, msgType: msgType}
-    ];
+            {msg: {sum: sum}, metadata: metadata, msgType: msgType},
+            {msg: {difference: diff}, metadata: metadata, msgType: msgType}
+       ];
 ```
 
 <br>