diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index d76c98aa10..767f3b78e4 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,7 +1,19 @@
 variables:
   SHOTGUN_TEST_VERSION:
     value: "$CI_COMMIT_SHA"
-    description: "version to be tested"
+    description: "version(s) to be tested (commit or branch or tag name)"
+  SHOTGUN_SCENARIO:
+    value: "udp"
+    description: "protocol combination(s) to be tested, must be one of https://gitlab.nic.cz/knot/resolver-benchmarking/-/tree/master/roles/shotgun/files"
+  SHOTGUN_DURATION:
+    value: 60
+    description: "test length in seconds, max 900 s"
+  SHOTGUN_TRAFFIC_MULTIPLIER:
+    value: 10
+    description: "client traffic volume multiplier(s); base value 1 = roughly 8 k QPS; start with multiplier 10; max. 40"
+  SHOTGUN_ROUNDS:
+    value: 3
+    description: "repeat test for each combination of (version, scenario, traffic multiplier) this many times; test against reference v9_11_31 is always run once; three runs recommended so we can detect noise"
 
 stages:
   - performance