diff --git a/README.md b/README.md
index 7f8ce5a..0d0ef68 100644
--- a/README.md
+++ b/README.md
@@ -45,12 +45,14 @@ The adapter requires the `RADICLE_NATIVE_CI` environment variable to
 be set to the filename of a configuration file in YAML. For example:
 
 ~~~yaml
+base_url: https://ci.example.org/state
 state: /srv/http
 log: /home/_rad/native-ci.log
 ~~~
 
 The fields are:
 
+* `base_url` --- base URL for build logs (mandatory for access from CI broker page)
 * `state` --- required, directory where per-run directories are stored
 * `log` --- required, file where native CI should write a log
 * `timeout` --- optional, maximum duration of the run, in seconds