diff --git a/packages/core/src/commands/clearContent.ts b/packages/core/src/commands/clearContent.ts
index fb749162..e93325e7 100644
--- a/packages/core/src/commands/clearContent.ts
+++ b/packages/core/src/commands/clearContent.ts
@@ -1,14 +1,14 @@
 import { Editor } from '../Editor'
 
-type ClearContent = (emitUpdate?: Boolean) => any
+type ClearContentCommand = (emitUpdate?: Boolean) => Editor
 
 declare module '../Editor' {
   interface Editor {
-    clearContent: ClearContent,
+    clearContent: ClearContentCommand,
   }
 }
 
-export default (next: Function, editor: Editor): ClearContent => (emitUpdate = false) => {
+export default (next: Function, editor: Editor) => (emitUpdate = false) => {
   editor.setContent('', emitUpdate)
   next()
 }
diff --git a/packages/core/src/commands/deleteSelection.ts b/packages/core/src/commands/deleteSelection.ts
index 1a67e086..63bbd7a3 100644
--- a/packages/core/src/commands/deleteSelection.ts
+++ b/packages/core/src/commands/deleteSelection.ts
@@ -1,15 +1,15 @@
 import { Editor } from '../Editor'
 import { deleteSelection } from 'prosemirror-commands'
 
-type DeleteSelection = () => any
+type DeleteSelectionCommand = () => Editor
 
 declare module '../Editor' {
   interface Editor {
-    deleteSelection: DeleteSelection,
+    deleteSelection: DeleteSelectionCommand,
   }
 }
 
-export default (next: Function, { state, view }: Editor): DeleteSelection => () => {
+export default (next: Function, { state, view }: Editor) => () => {
   deleteSelection(state, view.dispatch)
   next()
 }
diff --git a/packages/core/src/commands/focus.ts b/packages/core/src/commands/focus.ts
index 1263edbd..357e9655 100644
--- a/packages/core/src/commands/focus.ts
+++ b/packages/core/src/commands/focus.ts
@@ -3,9 +3,11 @@ import { TextSelection } from 'prosemirror-state'
 import sleep from '../utils/sleep'
 import minMax from '../utils/minMax'
 
+type FocusCommand = (position?: Position) => Editor
+
 declare module '../Editor' {
   interface Editor {
-    focus(position?: Position): Editor,
+    focus: FocusCommand
   }
 }
 
diff --git a/packages/core/src/commands/insertHTML.ts b/packages/core/src/commands/insertHTML.ts
index a09a33ef..e274a0b0 100644
--- a/packages/core/src/commands/insertHTML.ts
+++ b/packages/core/src/commands/insertHTML.ts
@@ -2,15 +2,15 @@ import { DOMParser } from 'prosemirror-model'
 import { Editor } from '../Editor'
 import elementFromString from '../utils/elementFromString'
 
-type InsertHTML = (value: string) => any
+type InsertHTMLCommand = (value: string) => Editor
 
 declare module '../Editor' {
   interface Editor {
-    insertHTML: InsertHTML,
+    insertHTML: InsertHTMLCommand,
   }
 }
 
-export default (next: Function, editor: Editor): InsertHTML => value => {
+export default (next: Function, editor: Editor) => (value: string) => {
   const { view, state } = editor
   const { selection } = state
   const element = elementFromString(value)
diff --git a/packages/core/src/commands/insertText.ts b/packages/core/src/commands/insertText.ts
index 4877ca2d..49043046 100644
--- a/packages/core/src/commands/insertText.ts
+++ b/packages/core/src/commands/insertText.ts
@@ -1,14 +1,14 @@
 import { Editor } from '../Editor'
 
-type InsertText = (value: string) => any
+type InsertTextCommand = (value: string) => Editor
 
 declare module '../Editor' {
   interface Editor {
-    insertText: InsertText,
+    insertText: InsertTextCommand,
   }
 }
 
-export default (next: Function, editor: Editor): InsertText => value => {
+export default (next: Function, editor: Editor) => (value: string) => {
   const { view, state } = editor
   const transaction = state.tr.insertText(value)
 
diff --git a/packages/core/src/commands/removeMark.ts b/packages/core/src/commands/removeMark.ts
index d9a8a47a..8c62ff1c 100644
--- a/packages/core/src/commands/removeMark.ts
+++ b/packages/core/src/commands/removeMark.ts
@@ -3,15 +3,15 @@ import { MarkType } from 'prosemirror-model'
 import getMarkType from '../utils/getMarkType'
 import getMarkRange from '../utils/getMarkRange'
 
-type RemoveMark = (type: string | MarkType) => any
+type RemoveMarkCommand = (typeOrName: string | MarkType) => Editor
 
 declare module '../Editor' {
   interface Editor {
-    toggleMark: RemoveMark,
+    toggleMark: RemoveMarkCommand,
   }
 }
 
-export default (next: Function, editor: Editor): RemoveMark => typeOrName => {
+export default (next: Function, editor: Editor) => (typeOrName: string | MarkType) => {
   const { view, state, schema } = editor
   const { tr, selection } = state
   const type = getMarkType(typeOrName, schema)
diff --git a/packages/core/src/commands/removeMarks.ts b/packages/core/src/commands/removeMarks.ts
index 5514a60d..f838916e 100644
--- a/packages/core/src/commands/removeMarks.ts
+++ b/packages/core/src/commands/removeMarks.ts
@@ -1,14 +1,14 @@
 import { Editor } from '../Editor'
 
-type RemoveMarks = () => any
+type RemoveMarksCommand = () => Editor
 
 declare module '../Editor' {
   interface Editor {
-    removeMarks: RemoveMarks,
+    removeMarks: RemoveMarksCommand,
   }
 }
 
-export default (next: Function, editor: Editor): RemoveMarks => () => {
+export default (next: Function, editor: Editor) => () => {
   const { state, view, schema } = editor
   const { selection, tr } = state
   const { from, to, empty } = selection
diff --git a/packages/core/src/commands/replaceWithNode.ts b/packages/core/src/commands/replaceWithNode.ts
index 3d624595..ffdcf87f 100644
--- a/packages/core/src/commands/replaceWithNode.ts
+++ b/packages/core/src/commands/replaceWithNode.ts
@@ -7,19 +7,19 @@ interface Range {
   to: number,
 }
 
-type ReplaceWithNode = (
-  type: NodeType,
+type ReplaceWithNodeCommand = (
+  typeOrName: NodeType,
   attrs: {},
   range?: Range,
-) => any
+) => Editor
 
 declare module '../Editor' {
   interface Editor {
-    replaceText: ReplaceWithNode,
+    replaceText: ReplaceWithNodeCommand,
   }
 }
 
-export default (next: Function, editor: Editor): ReplaceWithNode => (typeOrName, attrs, range) => {
+export default (next: Function, editor: Editor) => (typeOrName: NodeType, attrs: {}, range?: Range) => {
   const { view, state, schema } = editor
   const { $from, $to } = state.selection
   const type = getNodeType(typeOrName, schema)
diff --git a/packages/core/src/commands/selectAll.ts b/packages/core/src/commands/selectAll.ts
index 6d08a2c5..39b7b1a6 100644
--- a/packages/core/src/commands/selectAll.ts
+++ b/packages/core/src/commands/selectAll.ts
@@ -1,15 +1,15 @@
 import { Editor } from '../Editor'
 import { selectAll } from 'prosemirror-commands'
 
-type SelectAll = () => any
+type SelectAllCommand = () => Editor
 
 declare module '../Editor' {
   interface Editor {
-    selectAll: SelectAll,
+    selectAll: SelectAllCommand,
   }
 }
 
-export default (next: Function, { state, view }: Editor): SelectAll => () => {
+export default (next: Function, { state, view }: Editor) => () => {
   selectAll(state, view.dispatch)
   next()
 }
diff --git a/packages/core/src/commands/selectParentNode.ts b/packages/core/src/commands/selectParentNode.ts
index 0d22582c..73ef2466 100644
--- a/packages/core/src/commands/selectParentNode.ts
+++ b/packages/core/src/commands/selectParentNode.ts
@@ -1,15 +1,15 @@
 import { Editor } from '../Editor'
 import { selectParentNode } from 'prosemirror-commands'
 
-type SelectParentNode = () => any
+type SelectParentNodeCommand = () => Editor
 
 declare module '../Editor' {
   interface Editor {
-    selectParentNode: SelectParentNode,
+    selectParentNode: SelectParentNodeCommand,
   }
 }
 
-export default (next: Function, { state, view }: Editor): SelectParentNode => () => {
+export default (next: Function, { state, view }: Editor) => () => {
   selectParentNode(state, view.dispatch)
   next()
 }
diff --git a/packages/core/src/commands/setContent.ts b/packages/core/src/commands/setContent.ts
index f2e9d541..7c18b726 100644
--- a/packages/core/src/commands/setContent.ts
+++ b/packages/core/src/commands/setContent.ts
@@ -1,19 +1,19 @@
 import { Editor } from '../Editor'
 import { TextSelection } from 'prosemirror-state'
 
-type SetContent = (
+type SetContentCommand = (
   content: string,
   emitUpdate?: Boolean,
   parseOptions?: any,
-) => any
+) => Editor
 
 declare module '../Editor' {
   interface Editor {
-    setContent: SetContent,
+    setContent: SetContentCommand,
   }
 }
 
-export default (next: Function, editor: Editor): SetContent => (content, emitUpdate = false, parseOptions = {}) => {
+export default (next: Function, editor: Editor) => (content: string, emitUpdate: Boolean = false, parseOptions = {}) => {
   if (content === null) {
     next()
     return
diff --git a/packages/core/src/commands/toggleMark.ts b/packages/core/src/commands/toggleMark.ts
index 8441a272..62374342 100644
--- a/packages/core/src/commands/toggleMark.ts
+++ b/packages/core/src/commands/toggleMark.ts
@@ -3,15 +3,15 @@ import { toggleMark } from 'prosemirror-commands'
 import { MarkType } from 'prosemirror-model'
 import getMarkType from '../utils/getMarkType'
 
-type ToggleMark = (type: string | MarkType) => any
+type ToggleMarkCommand = (typeOrName: string | MarkType) => Editor
 
 declare module '../Editor' {
   interface Editor {
-    toggleMark: ToggleMark,
+    toggleMark: ToggleMarkCommand,
   }
 }
 
-export default (next: Function, editor: Editor): ToggleMark => (typeOrName) => {
+export default (next: Function, editor: Editor) => (typeOrName: string | MarkType) => {
   const { view, state, schema } = editor
   const type = getMarkType(typeOrName, schema)
 
diff --git a/packages/core/src/commands/toggleNode.ts b/packages/core/src/commands/toggleNode.ts
index 32ab13d0..e654ad20 100644
--- a/packages/core/src/commands/toggleNode.ts
+++ b/packages/core/src/commands/toggleNode.ts
@@ -4,19 +4,19 @@ import { Editor } from '../Editor'
 import nodeIsActive from '../utils/nodeIsActive'
 import getNodeType from '../utils/getNodeType'
 
-type ToggleNode = (
-  type: string | NodeType,
+type ToggleNodeCommand = (
+  typeOrName: string | NodeType,
   toggleType: string | NodeType,
   attrs?: {}
-) => any
+) => Editor
 
 declare module '../Editor' {
   interface Editor {
-    toggleNode: ToggleNode,
+    toggleNode: ToggleNodeCommand,
   }
 }
 
-export default (next: Function, editor: Editor): ToggleNode => (typeOrName, toggleTypeOrName, attrs) => {
+export default (next: Function, editor: Editor) => (typeOrName: string | NodeType, toggleTypeOrName: string | NodeType, attrs = {}) => {
   const { view, state, schema } = editor
   const type = getNodeType(typeOrName, schema)
   const toggleType = getNodeType(toggleTypeOrName, schema)
diff --git a/packages/core/src/commands/updateMark.ts b/packages/core/src/commands/updateMark.ts
index e5d81eef..a0f535e6 100644
--- a/packages/core/src/commands/updateMark.ts
+++ b/packages/core/src/commands/updateMark.ts
@@ -3,18 +3,18 @@ import { MarkType } from 'prosemirror-model'
 import getMarkType from '../utils/getMarkType'
 import getMarkRange from '../utils/getMarkRange'
 
-type UpdateMark = (
-  type: string | MarkType,
+type UpdateMarkCommand = (
+  typeOrName: string | MarkType,
   attrs: {},
-) => any
+) => Editor
 
 declare module '../Editor' {
   interface Editor {
-    updateMark: UpdateMark,
+    updateMark: UpdateMarkCommand,
   }
 }
 
-export default (next: Function, editor: Editor): UpdateMark => (typeOrName, attrs) => {
+export default (next: Function, editor: Editor) => (typeOrName: string | MarkType, attrs = {}) => {
   const { view, state, schema } = editor
   const { tr, selection, doc } = state
   let { from, to, $from, empty } = selection