diff --git a/docs/walkthrough.md b/docs/walkthrough.md
index 364025f..d5a2871 100644
--- a/docs/walkthrough.md
+++ b/docs/walkthrough.md
@@ -40,7 +40,7 @@ This walkthrough serves as the primary onboarding guide for new developers and e
 
 msghandler implements the **Claim-Check pattern** for efficient handling of large payloads (>0.5MB):
 
-### 2.0 Transport Layer Pattern
+### 2.1 Transport Layer Pattern
 
 **Critical**: msghandler is **transport-agnostic**. The caller is responsible for: