diff --git a/ui-ngx/src/app/modules/home/components/calculated-fields/components/panel/calculated-field-argument-panel.component.html b/ui-ngx/src/app/modules/home/components/calculated-fields/components/panel/calculated-field-argument-panel.component.html
index 7521395cb4..92855d882f 100644
--- a/ui-ngx/src/app/modules/home/components/calculated-fields/components/panel/calculated-field-argument-panel.component.html
+++ b/ui-ngx/src/app/modules/home/components/calculated-fields/components/panel/calculated-field-argument-panel.component.html
@@ -55,11 +55,11 @@
                       class="tb-error">
               warning
             </mat-icon>
-          } @else if (argumentFormGroup.get('argumentName').touched && argumentFormGroup.get('argumentName').hasError('equalCtx')) {
+          } @else if (argumentFormGroup.get('argumentName').touched && argumentFormGroup.get('argumentName').hasError('forbiddenName')) {
             <mat-icon matSuffix
                       matTooltipPosition="above"
                       matTooltipClass="tb-error-tooltip"
-                      [matTooltip]="'calculated-fields.hint.argument-name-ctx' | translate"
+                      [matTooltip]="'calculated-fields.hint.argument-name-forbidden' | translate"
                       class="tb-error">
               warning
             </mat-icon>
diff --git a/ui-ngx/src/app/modules/home/components/calculated-fields/components/panel/calculated-field-argument-panel.component.ts b/ui-ngx/src/app/modules/home/components/calculated-fields/components/panel/calculated-field-argument-panel.component.ts
index 2a64c90f20..6f46e47af9 100644
--- a/ui-ngx/src/app/modules/home/components/calculated-fields/components/panel/calculated-field-argument-panel.component.ts
+++ b/ui-ngx/src/app/modules/home/components/calculated-fields/components/panel/calculated-field-argument-panel.component.ts
@@ -67,7 +67,7 @@ export class CalculatedFieldArgumentPanelComponent implements OnInit, AfterViewI
   readonly defaultLimit = Math.floor(this.maxDataPointsPerRollingArg / 10);
 
   argumentFormGroup = this.fb.group({
-    argumentName: ['', [Validators.required, this.uniqNameRequired(), this.notEqualCtxValidator(), Validators.pattern(charsWithNumRegex), Validators.maxLength(255)]],
+    argumentName: ['', [Validators.required, this.uniqNameRequired(), this.forbiddenArgumentNameValidator(), Validators.pattern(charsWithNumRegex), Validators.maxLength(255)]],
     refEntityId: this.fb.group({
       entityType: [ArgumentEntityType.Current],
       id: ['']
@@ -254,10 +254,11 @@ export class CalculatedFieldArgumentPanelComponent implements OnInit, AfterViewI
     }
   }
 
-  private notEqualCtxValidator(): ValidatorFn {
+  private forbiddenArgumentNameValidator(): ValidatorFn {
     return (control: FormControl) => {
       const trimmedValue = control.value.trim().toLowerCase();
-      return trimmedValue === 'ctx' ? { equalCtx: true } : null;
+      const forbiddenArgumentNames = ['ctx', 'e', 'pi'];
+      return forbiddenArgumentNames.includes(trimmedValue) ? { forbiddenName: true } : null;
     };
   }
 
diff --git a/ui-ngx/src/assets/locale/locale.constant-en_US.json b/ui-ngx/src/assets/locale/locale.constant-en_US.json
index e4f4721f3c..133e333dbe 100644
--- a/ui-ngx/src/assets/locale/locale.constant-en_US.json
+++ b/ui-ngx/src/assets/locale/locale.constant-en_US.json
@@ -1069,7 +1069,7 @@
             "argument-name-pattern": "Argument name is invalid.",
             "argument-name-duplicate": "Argument with such name already exists.",
             "argument-name-max-length": "Argument name should be less than 256 characters.",
-            "argument-name-ctx": "Argument name 'ctx' is reserved and cannot be used.",
+            "argument-name-forbidden": "Argument name is reserved and cannot be used.",
             "argument-type-required": "Argument type is required.",
             "max-args": "Maximum number of arguments reached.",
             "decimals-range": "Decimals by default should be a number between 0 and 15.",