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docs/architecture.md

@@ -388,6 +388,12 @@ graph TD
 - **Julia:** Uses `NATS_connection` keyword parameter with function overloading
 - **JavaScript/Python:** Achieved by creating NATS client outside the function and reusing it in custom handlers
 
+**Note on `is_publish`:**
+- `is_publish` is simply a switch to control automatic publishing
+- When `true` (default): Message is published to NATS automatically
+- When `false`: Returns `(env, env_json_str)` without publishing, allowing manual publishing
+- Connection reuse is achieved separately by creating NATS client outside the function
+
 ### Julia Implementation
 
 #### Dependencies