The Citations feature of the Anthropic API is a powerful technology that allows the Claude model to cite exact sentences and paragraphs from source documents while generating answers. This feature not only enhances the verifiability and credibility of the responses but also reduces the likelihood of model hallucination issues. The Citations feature is based on the Anthropic API and is suitable for a variety of scenarios that require verification of AI-generated content sources, such as document summarization, complex Q&A, and customer support. Its pricing follows a standard token-based model, and users do not have to pay for output tokens that return quoted text.