  Facing increasingly complex BIM authoring software and the accompanying
expensive learning costs, designers often seek to interact with the software in
a more intelligent and lightweight manner. They aim to automate modeling
workflows, avoiding obstacles and difficulties caused by software usage,
thereby focusing on the design process itself. To address this issue, we
proposed an LLM-based autonomous agent framework that can function as a copilot
in the BIM authoring tool, answering software usage questions, understanding
the user's design intentions from natural language, and autonomously executing
modeling tasks by invoking the appropriate tools. In a case study based on the
BIM authoring software Vectorworks, we implemented a software prototype to
integrate the proposed framework seamlessly into the BIM authoring scenario. We
evaluated the planning and reasoning capabilities of different LLMs within this
framework when faced with complex instructions. Our work demonstrates the
significant potential of LLM-based agents in design automation and intelligent
interaction.
