diff --git a/README.md b/README.md
index 28b8b9e..ff9819f 100644
--- a/README.md
+++ b/README.md
@@ -57,19 +57,26 @@ The server responds on the following URLs:
 URL                  |Method |Description
 ---------------------|-------|---
 `/get/{ID}`          |`GET`  |Download item content
+`/p/{ID}`            |`GET`  |Preview item content (HTML)
+`/p/{ID}-{ID}-...`   |`GET`  |Preview multiple item content (HTML)
 `/info/{ID}`         |`GET`  |Get item content metadata (JSON)
-`/thumb/{Type}/{ID}` |`GET`  |Get item thumbnail image
+`/thumb/{Type}/{ID}` |`GET`  |Get item thumbnail image (JPEG). "Type" should match `[sbtmlh]`.
 `/about`             |`GET`  |Get server metadata (JSON)
 
 ## Usage (Embedding for web)
 
-Your webpage should load the SDK from the contented server, then call the `contented.init` function to display the upload widget over the top of an existing DOM element. Your callback will be passed an array of file IDs of any uploaded items.
+Your webpage should load the SDK from the contented server, then call the `contented.init` function to display the upload widget over the top of an existing DOM element:
 
 ```html
 <script type="text/javascript" src="SERVER_ADDR/sdk.js"></script>
-contented.init("#target", function(/* String[] */ items) {});
+contented.init("#target");
 ```
 
+You can optionally supply additional ordered parameters to `contented.init`:
+
+1. A callback, that will be passed an array of file IDs of any uploaded items
+2. A callback, that will be called if the SDK widget is closed
+
 ## Changelog
 
 2020-07-25: 1.3.1