Is Mastra usuable in the browser directly? Framework deployment only deals with a fullstack approach. The same question is not much detailed by LangGraph either (https://langchain-ai.github.io/langgraphjs/how-tos/use-in-web-environments/) , though it seems to kinda work if you are ok with a slightly hacky solution. The cool thing with in browser agent is that you can load a user API key from the localStorage, it works well for crafting tiny AI-apps. I am aware of the Mastra client SDK but I mean running the actual agent with client-server communication.