diff --git a/docs/manuals/cli.md b/docs/manuals/cli.md
index 9a55a333..b86d4e6b 100644
--- a/docs/manuals/cli.md
+++ b/docs/manuals/cli.md
@@ -3,3 +3,7 @@
 The PVC CLI client is built with Click, a Python framework for creating self-documenting CLI applications. It interfaces directly with the Zookeeper cluster to send and receive information about the cluster with no authentication.
 
 Use the `-h` option at any level of the `pvc` CLI command to receive help about the available commands and options.
+
+## Configuration
+
+The CLI client requires no configuration file. The only optional external environment variable is `PVC_ZOOKEEPER_HOST`, which accepts a Zookeeper connection string and replaces the argument `-z` to the CLI command.