Why persisting Message Thread implementation ignored the messages for role - System?

For example, I access the Mastra Agents via POST: /agents/<agentId>/stream { // if these parameters are present - messages for role - system is ignored "threadId": "sample-tread-id123433345435555", "resourceId": "sample-tread-id123433345435555", "runId": "sample-tread-id12343332454",
"messages": [ { "role": "user", "content": "okay, my name is Prinzessin Friederike Schleswig-Holstein-Sonderburg-Glücksburg, " }, // ignored when threadId and ResourceId is present { "role": "system", "content": "You are always put jokes in your conversation and also always say Super!!!!" } ] } I am using this module: mastra/core@0.15.x I notice this when I tried to check the parameters passed from Agent to the Model ( see attachment ) - you will the system message that I included in the request is removed / ignored