diff --git a/README.md b/README.md
index f2e2ab8..6284f7a 100644
--- a/README.md
+++ b/README.md
@@ -277,6 +277,10 @@ The `racketmq/` directory also contains a few other files of interest:
  - `run`: [Daemontools](https://cr.yp.to/daemontools.html) startup script for the server
  - `log/run`: Daemontools logging startup script for the server
  - `htdocs/`: Static files to be served by the server
+    - `htdocs/500.html`: Error document used by nginx when it cannot reach RacketMQ
+    - `htdocs/client.html`: Simple interactive tool for experimenting
+      with WebSocket subscriptions in the browser
+    - `htdocs/client.js`: JavaScript code for `client.html`
 
 ## Bug Reports