diff --git a/README.md b/README.md
index c42e73e..199e491 100644
--- a/README.md
+++ b/README.md
@@ -9,7 +9,7 @@ Built on Protocol Buffers with a fixed 4-byte length-prefixed framing, type-base
 ## Design Principles
 
 - Keep the core transport layer thin and stable
-- Provide only the minimum common foundation for cross-language communication
+- Provide only the minimum common foundation for cross-language communication5
 - Standardize framing, serialization, routing, request-response correlation, and heartbeat
 - Do not embed application semantics into the protocol core
 - Domain-specific concerns such as auth, session, agent workflow, chat features, and game logic belong in upper-layer implementations