Generative artificial intelligence (GenAI) tools have technical advantages in enhancing the information cataloging and retrieval capabilities of libraries, predicting user needs and providing personalized assistance, supporting information literacy cultivation and participating in collection services decision-making. They have been applied in aspects such as improving user assistance, optimizing content generation, enhancing retrieval recommendations, supporting literacy cultivation and participating in service decision-making in library knowledge services. Embedding generative artificial intelligence tools into library knowledge services faces multiple challenges such as errors and distortions in generated content, data privacy violations and leaks, input-output biases, and trust barriers among user groups. It is urgent to take systematic development measures such as creating an intelligence-driven content verification framework, designing an algorithm governance architecture, building an information security guarantee system, and cultivating professional teams to ensure the sustainable development of library knowledge services in the contect of the digital intelligence era.