diff --git a/var/spack/repos/builtin/packages/g4tendl/package.py b/var/spack/repos/builtin/packages/g4tendl/package.py
index 19c49d5e561..b7116fb716d 100644
--- a/var/spack/repos/builtin/packages/g4tendl/package.py
+++ b/var/spack/repos/builtin/packages/g4tendl/package.py
@@ -7,7 +7,7 @@
 
 
 class G4tendl(Package):
-    """Geant4 data for incident particles [optional]"""
+    """Optional Geant4 data for incident particles."""
 
     homepage = "https://geant4.web.cern.ch"
     url = "https://geant4-data.web.cern.ch/geant4-data/datasets/G4TENDL.1.3.tar.gz"