diff --git a/.claude/skills/git-commit/SKILL.md b/.claude/skills/git-commit/SKILL.md
index c11d5e8f0..a76dfd74f 100644
--- a/.claude/skills/git-commit/SKILL.md
+++ b/.claude/skills/git-commit/SKILL.md
@@ -47,9 +47,15 @@ allowed-tools: Bash, Read, Grep, Glob, Write, Edit
 
 <optional body — what and why, not how>
 
-Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
+Co-Authored-By: Claude <noreply@anthropic.com>
 ```
 
+The trailer is intentionally **unpinned** — do not write a model version into the
+example. The model-identifier variant the Claude Code harness appends automatically
+(e.g. `Co-Authored-By: Claude Opus <version> <noreply@anthropic.com>`) is equally
+valid; leave it as the harness emits it. Pinned version numbers are the root cause of
+attribution drift (this line read `Claude Opus 4.6` for months after the model moved on).
+
 ### Types
 
 | Type | Use for |