fix: use server-side session map for claude-agent-sdk conversation memory

Instead of round-tripping claude_session_id through the frontend,
maintain an in-memory runtimeSessionId -> claude_session_id mapping
on the backend. Both are lost on container restart, so in-memory
storage is sufficient. No frontend changes required.

Author: iprivit

patterns/claude-agent-sdk-multi-agent/agent.py

@@ -27,6 +27,10 @@
 
 app = BedrockAgentCoreApp()
 
+# Maps runtimeSessionId -> claude_session_id for conversation resumption.
+# Both are lost if the container restarts, so in-memory storage is sufficient.
+_session_map: dict[str, str] = {}
+
 
 @app.entrypoint
 async def main(payload, context: RequestContext):
@@ -46,7 +50,7 @@ async def main(payload, context: RequestContext):
         return
 
     code_int_session_id = payload.get("code_int_session_id", "")
-    claude_session_id = payload.get("claude_session_id")
+    claude_session_id = _session_map.get(runtime_session_id)
 
     # Extract user ID securely from validated JWT token
     user_id = extract_user_id_from_context(context)
@@ -171,6 +175,8 @@ async def _process_messages(options: ClaudeAgentOptions):
                                         pass
                 elif isinstance(msg, ResultMessage):
                     logger.info("ResultMessage received, session_id=%s", msg.session_id)
+                    if msg.session_id:
+                        _session_map[runtime_session_id] = msg.session_id
                     yield {"claude_session_id": msg.session_id}
 
     try:

patterns/claude-agent-sdk-single-agent/agent.py

@@ -26,6 +26,10 @@
 
 app = BedrockAgentCoreApp()
 
+# Maps runtimeSessionId -> claude_session_id for conversation resumption.
+# Both are lost if the container restarts, so in-memory storage is sufficient.
+_session_map: dict[str, str] = {}
+
 
 @app.entrypoint
 async def main(payload, context: RequestContext):
@@ -45,7 +49,7 @@ async def main(payload, context: RequestContext):
         return
 
     code_int_session_id = payload.get("code_int_session_id", "")
-    claude_session_id = payload.get("claude_session_id")
+    claude_session_id = _session_map.get(runtime_session_id)
 
     # Extract user ID securely from validated JWT token
     user_id = extract_user_id_from_context(context)
@@ -158,6 +162,8 @@ async def _process_messages(options: ClaudeAgentOptions):
                                         pass
                 elif isinstance(msg, ResultMessage):
                     logger.info("ResultMessage received, session_id=%s", msg.session_id)
+                    if msg.session_id:
+                        _session_map[runtime_session_id] = msg.session_id
                     yield {"claude_session_id": msg.session_id}
 
     try: