diff --git a/packages/block-editor/README.md b/packages/block-editor/README.md
index a4f0b1d566f52..2427de60c4577 100644
--- a/packages/block-editor/README.md
+++ b/packages/block-editor/README.md
@@ -272,7 +272,21 @@ Undocumented declaration.
 
 <a name="coreDeviceTypes" href="#coreDeviceTypes">#</a> **coreDeviceTypes**
 
-Undocumented declaration.
+An array of strings that represent `deviceType` values that belong to the
+block editor core system.
+
+When the `deviceType` returned by `__experimentalGetPreviewDeviceType()`, is
+one of these values, the built-in `VisualEditor` is responsible for rendering
+a preview of that type.
+
+When the `deviceType` is something other than one of the `coreDeviceTypes`,
+we are rendering a custom preview registered by the
+`<PluginPreviewMenuItem />` and `<PluginPreview />` components, and defer to
+a `<Slot />` filled by the plugin to draw the preview.
+
+_Type_
+
+-   `Array`
 
 <a name="createCustomColorsHOC" href="#createCustomColorsHOC">#</a> **createCustomColorsHOC**
 
diff --git a/packages/block-editor/src/components/preview-options/index.js b/packages/block-editor/src/components/preview-options/index.js
index 70d96652c7227..ef5491690e2ba 100644
--- a/packages/block-editor/src/components/preview-options/index.js
+++ b/packages/block-editor/src/components/preview-options/index.js
@@ -24,17 +24,20 @@ const {
 
 export { PluginPreviewMenuFill };
 
-/*
- * coreDeviceTypes: An array of strings. The strings returned represent
- * deviceType values that belong to the core system. When the deviceType,
- * returned by `__experimentalGetPreviewDeviceType()`, is one of these values,
- * the built in VisualEditor is responsible for rendering a preview of that
- * type.
-
- * When the deviceType is something other than one of the coreDeviceTypes, we are
- * rendering a custom deviceType registered by the <PluginPreviewMenuItem /> and
- * <PluginPreview /> components, and defer to a <Slot /> filled by the plugin to
- * draw the preview.
+/**
+ * An array of strings that represent `deviceType` values that belong to the
+ * block editor core system.
+ *
+ * When the `deviceType` returned by `__experimentalGetPreviewDeviceType()`, is
+ * one of these values, the built-in `VisualEditor` is responsible for rendering
+ * a preview of that type.
+ *
+ * When the `deviceType` is something other than one of the `coreDeviceTypes`,
+ * we are rendering a custom preview registered by the
+ * `<PluginPreviewMenuItem />` and `<PluginPreview />` components, and defer to
+ * a `<Slot />` filled by the plugin to draw the preview.
+ *
+ * @type {Array}
  */
 export const coreDeviceTypes = [ 'Desktop', 'Tablet', 'Mobile' ];