Add some type docs

src/components/Toast/types.ts

@@ -2,9 +2,23 @@ export type ToastType = 'default' | 'success' | 'error' | 'warning' | 'info'
 
 export type ToastApi = {
   show: (props: {
+    /**
+     * The type of toast to show. This determines the styling and icon used.
+     */
     type: ToastType
-    content: React.ReactNode
+    /**
+     * A string, `Text`, or `Span` components to render inside the toast. This
+     * allows additional formatting of the content, but should not be used for
+     * interactive elements link links or buttons.
+     */
+    content: React.ReactNode | string
+    /**
+     * Accessibility label for the toast, used for screen readers.
+     */
     a11yLabel: string
+    /**
+     * Defaults to `DEFAULT_TOAST_DURATION` from `#components/Toast/const`.
+     */
     duration?: number
   }) => void
 }