diff --git a/.env.example b/.env.example
index 3567be1..c6c8a04 100644
--- a/.env.example
+++ b/.env.example
@@ -18,7 +18,10 @@ WS_AUTH_REQUIRED=false
 WS_AUTH_SECRET=
 
 # Solana
-SOLANA_RPC_URL=https://api.mainnet-beta.solana.com
+# The shared library reads RPC_URL (not SOLANA_RPC_URL).
+# For mainnet: use a paid RPC provider (Helius, Alchemy, etc.) — the public
+# endpoint rate-limits aggressively and is unsuitable for production.
+RPC_URL=https://api.mainnet-beta.solana.com
 
 # Supabase
 SUPABASE_URL=