diff --git a/CLAUDE.md b/CLAUDE.md
index 5feb8edf25..8fa356b2b2 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -70,6 +70,9 @@ yarn compile-dbg
 ### Commits
 BitGoJS uses conventional commits. All commits MUST pass the spec described in `commitlint.config.js`.
 
+### TypeScript Guidelines
+- **Avoid `any` type**: Use specific types, interfaces, or union types instead of `any`. If absolutely necessary, prefer `unknown` and use type guards for safety.
+
 ## Code Architecture
 
 BitGoJS is a monorepo composed of multiple modules, each implementing specific functionality: