This $799,999 Project Grant award from the National Science Foundation's Computer and Information Science and Engineering (CFDA 47.070) program supports the development of novel methods, evaluations, and applications to leverage large language models (LLMs) as "tools for thought" to enhance creative, open-ended, and collaborative work. The key objectives are to: 1) integrate LLMs into interactive systems while ensuring output quality, 2) help users generate diverse yet relevant ideas, and 3) support cooperative multi-user and LLM workflows. The project, led by the University of Washington, aims to go beyond current chat-based LLM interactions to provide reliable and effective LLM-powered systems for tasks such as scientific writing, text analysis, and design ideation. The award period runs from October 1, 2024 to September 30, 2028.