diff --git a/extensions/amp-story/amp-story.md b/extensions/amp-story/amp-story.md
index 57266b64ef6a4..1e2c95dc58ef6 100644
--- a/extensions/amp-story/amp-story.md
+++ b/extensions/amp-story/amp-story.md
@@ -379,6 +379,20 @@ This same image can be used for both mobile portrait and landscape desktop using
 <amp-img src="cat.jpg" alt="..." object-position="75% 40%"></amp-img>
 ```
 
+##### Optimize `amp-video` by using a free Google hosted video cache on origin documents
+
+The `<amp-video>` element on stories supports the Google video cache to be used on origin documents through the attribute `cache="google"`. The video cache will fetch and store the video contents periodically, reducing serving costs for videos, and generating transcodes with different quality settings that adapt the bitrate to the network conditions.
+
+Use 720p videos or higher to take advantage of all the video transcodes and adaptive bitrate algorithms.
+
+Example:
+
+```html
+<amp-video layout="fill" poster="img.png" cache="google">
+  <source src="video.mp4" type="video/mp4">
+</amp-video>
+```
+
 ##### `data-text-background-color`
 
 The `data-text-background-color` attribute highlights the text of the element with a specified color. To highlight the entire block, add this attribute directly to the text element. To only highlight the text, add the attribute and text to an inner <span>. Note that works anywhere inside an `<amp-story-page>`, not just in `<amp-story-grid-layer>`.
diff --git a/extensions/amp-video/0.1/amp-video.md b/extensions/amp-video/0.1/amp-video.md
index 6d3cec8dc34ab..b71f3bfa23711 100644
--- a/extensions/amp-video/0.1/amp-video.md
+++ b/extensions/amp-video/0.1/amp-video.md
@@ -140,6 +140,13 @@ Indicates the album/collection the video was taken from, specified as a string.
 
 Indicates the name/title of the video, specified as a string. If not provided, the Media Session API helper uses either the `aria-label` attribute or falls back to the page's title.
 
+[filter formats="stories"]
+
+#### cache
+
+Indicates the Google video cache should store and serve the video by adding `cache="google"`. The video cache will fetch and store the video contents periodically, reducing serving costs for videos, and generating transcodes with different quality settings that adapt the bitrate to the network conditions.
+[/filter]
+
 ## Analytics
 
 `amp-video` supports analytics out of the box. See [video analytics](../../amp-analytics/amp-video-analytics.md) for more information.