diff --git a/README.md b/README.md
index e8eac27..b877771 100644
--- a/README.md
+++ b/README.md
@@ -273,11 +273,13 @@ container.
 
 ## Operating it
 
-**Backup.** Everything durable is the SimpleX database on the volume:
-`simplex_chat.db` and `simplex_agent.db`. Stop the container before
-copying them, since a copy taken from under the running client can be
-inconsistent. The database holds the bot's keys, so a copy lets its
-holder answer as the bot; keep it as private as the running instance.
+**Backup.** Everything durable is on the volume: the SimpleX database,
+`simplex_chat.db` and `simplex_agent.db`, and the API credential,
+`api-token`. Stop the container before copying the database, since a
+copy taken from under the running client can be inconsistent. The
+database holds the bot's keys, so a copy lets its holder answer as the
+bot, and the credential lets its holder use the API; keep both as
+private as the running instance.
 
 **Upgrade.** Rebuild the image and recreate the container with the same
 volume. The chat client migrates its database on start. A newer