diff --git a/docs/project-conventions.md b/docs/project-conventions.md
index e72418b6..24ac63a1 100644
--- a/docs/project-conventions.md
+++ b/docs/project-conventions.md
@@ -7,6 +7,7 @@ Rules extracted from commit history that are specific to this project and not al
 - Imperative present tense, single-line, under 60 characters
 - Describe intent/behavior, not implementation details
 - Reverts use `Revert "Original message"` convention
+- NEVER ADD a co-authored by reference in the message body
 
 ## Architecture