diff --git a/CHANGELOG.md b/CHANGELOG.md
index b0ec738..7feec93 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -17,6 +17,12 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 <!-- ### Removed -->
 <!-- ### Fixed -->
 
+## Unreleased
+
+### Added
+
+- Added `commands` array to `CustomElementDeclaration` and `CustomElementMixinDeclaration` to document [Invoker Commands](https://developer.mozilla.org/en-US/docs/Web/API/Invoker_Commands_API) that a custom element responds to. ([#144](https://github.com/webcomponents/custom-elements-manifest/issues/144))
+
 ## [2.1.0] - 2024-05-16
 
 ### Added
diff --git a/examples/simple-element.json b/examples/simple-element.json
index fbd23e5..22eb983 100644
--- a/examples/simple-element.json
+++ b/examples/simple-element.json
@@ -35,6 +35,12 @@
               "name": "disabled"
             }
           ],
+          "commands": [
+            {
+              "name": "--show-modal",
+              "description": "Calls `showModal()` on the `<dialog>` element when invoked."
+            }
+          ],
           "superclass": {
             "name": "HTMLElement"
           }
diff --git a/schema.d.ts b/schema.d.ts
index edf3a21..81867b9 100644
--- a/schema.d.ts
+++ b/schema.d.ts
@@ -252,6 +252,12 @@ export interface CustomElement extends ClassLike {
 
   cssStates?: CssCustomState[];
 
+  /**
+   * The commands this element responds to.
+   * https://developer.mozilla.org/en-US/docs/Web/API/Invoker_Commands_API
+   */
+  commands?: Command[];
+
   demos?: Demo[];
 
   /**
@@ -402,6 +408,35 @@ export interface CssCustomState {
   deprecated?: boolean | string;
 }
 
+/**
+ * The description of a command that a custom element responds to.
+ * https://developer.mozilla.org/en-US/docs/Web/API/Invoker_Commands_API
+ */
+export interface Command {
+  /**
+   * The name of the command, e.g. `--show-modal`.
+   */
+  name: string;
+
+  /**
+   * A markdown summary suitable for display in a listing.
+   */
+  summary?: string;
+
+  /**
+   * A markdown description what the command does when invoked.
+   */
+  description?: string;
+
+  inheritedFrom?: Reference;
+
+  /**
+   * Whether the command is deprecated.
+   * If the value is a string, it's the reason for the deprecation.
+   */
+  deprecated?: boolean | string;
+}
+
 export interface CssCustomProperty {
   /**
    * The name of the property, including leading `--`.
diff --git a/schema.json b/schema.json
index 59ad67c..8a8a3dc 100644
--- a/schema.json
+++ b/schema.json
@@ -224,6 +224,37 @@
             ],
             "type": "object"
         },
+        "Command": {
+            "description": "The description of a command that a custom element responds to.\nhttps://developer.mozilla.org/en-US/docs/Web/API/Invoker_Commands_API",
+            "properties": {
+                "deprecated": {
+                    "description": "Whether the command is deprecated.\nIf the value is a string, it's the reason for the deprecation.",
+                    "type": [
+                        "string",
+                        "boolean"
+                    ]
+                },
+                "description": {
+                    "description": "A markdown description what the command does when invoked.",
+                    "type": "string"
+                },
+                "inheritedFrom": {
+                    "$ref": "#/definitions/Reference"
+                },
+                "name": {
+                    "description": "The name of the command, e.g. `--show-modal`.",
+                    "type": "string"
+                },
+                "summary": {
+                    "description": "A markdown summary suitable for display in a listing.",
+                    "type": "string"
+                }
+            },
+            "required": [
+                "name"
+            ],
+            "type": "object"
+        },
         "CssCustomProperty": {
             "properties": {
                 "default": {
@@ -323,6 +354,13 @@
                     },
                     "type": "array"
                 },
+                "commands": {
+                    "description": "The commands this element responds to.\nhttps://developer.mozilla.org/en-US/docs/Web/API/Invoker_Commands_API",
+                    "items": {
+                        "$ref": "#/definitions/Command"
+                    },
+                    "type": "array"
+                },
                 "cssParts": {
                     "items": {
                         "$ref": "#/definitions/CssPart"
@@ -473,6 +511,13 @@
                     },
                     "type": "array"
                 },
+                "commands": {
+                    "description": "The commands this element responds to.\nhttps://developer.mozilla.org/en-US/docs/Web/API/Invoker_Commands_API",
+                    "items": {
+                        "$ref": "#/definitions/Command"
+                    },
+                    "type": "array"
+                },
                 "cssParts": {
                     "items": {
                         "$ref": "#/definitions/CssPart"