diff --git a/.claude/CLAUDE.md b/.claude/CLAUDE.md
index 5523423f4..3f204b1e0 100644
--- a/.claude/CLAUDE.md
+++ b/.claude/CLAUDE.md
@@ -19,6 +19,7 @@ It holds policy and pointers only; facts live in the linked docs, and `./mfc.sh
     * Comments should be as short as possible without sacrificing value
     * GPU macros should follow the source's existing GPU macro principles and patterns
     * Functions/subroutines/modules shorter is better while being correct, fast, and separating concerns
+    * When a fix fails twice, stop and re-read in full the code you are changing, its callers and callees, and where each global it uses is set, before the next attempt. Repeated failures usually come from a detail remembered wrong
 
 ## Where to look