diff --git a/packages/extension-subscript/src/subscript.ts b/packages/extension-subscript/src/subscript.ts
index ead53e07..27dc1675 100644
--- a/packages/extension-subscript/src/subscript.ts
+++ b/packages/extension-subscript/src/subscript.ts
@@ -1,24 +1,24 @@
-import { Command, Mark, mergeAttributes } from '@tiptap/core'
+import { Mark, mergeAttributes } from '@tiptap/core'
 
 export interface SubscriptExtensionOptions {
   HTMLAttributes: Object,
 }
 
 declare module '@tiptap/core' {
-  interface Commands {
+  interface Commands<ReturnType> {
     subscript: {
       /**
        * Set a subscript mark
        */
-      setSubscript: () => Command,
+      setSubscript: () => ReturnType,
       /**
        * Toggle a subscript mark
        */
-      toggleSubscript: () => Command,
+      toggleSubscript: () => ReturnType,
       /**
        * Unset a subscript mark
        */
-      unsetSubscript: () => Command,
+      unsetSubscript: () => ReturnType,
     }
   }
 }
diff --git a/packages/extension-superscript/src/superscript.ts b/packages/extension-superscript/src/superscript.ts
index 1560dde5..6626ca2d 100644
--- a/packages/extension-superscript/src/superscript.ts
+++ b/packages/extension-superscript/src/superscript.ts
@@ -1,24 +1,24 @@
-import { Command, Mark, mergeAttributes } from '@tiptap/core'
+import { Mark, mergeAttributes } from '@tiptap/core'
 
 export interface SuperscriptExtensionOptions {
   HTMLAttributes: Object,
 }
 
 declare module '@tiptap/core' {
-  interface Commands {
+  interface Commands<ReturnType> {
     superscript: {
       /**
        * Set a superscript mark
        */
-      setSuperscript: () => Command,
+      setSuperscript: () => ReturnType,
       /**
        * Toggle a superscript mark
        */
-      toggleSuperscript: () => Command,
+      toggleSuperscript: () => ReturnType,
       /**
        * Unset a superscript mark
        */
-      unsetSuperscript: () => Command,
+      unsetSuperscript: () => ReturnType,
     }
   }
 }