What is the acceptable use of primary sources within a Wikipedia article?

Primary sources can be used in Wikipedia articles, but their use is limited and should be approached with caution. A primary source is a document or record that provides direct, firsthand evidence about an event, object, person, or work of art. Examples include original research papers, historical documents, autobiographies, and interviews. Primary sources can be used for straightforward, descriptive statements of facts that can be easily verified without interpretation. However, they should not be used to make analytical, evaluative, or interpretive claims. Any interpretation or analysis of a primary source should be supported by reliable secondary sources. It is generally preferable to cite secondary sources, which provide analysis and context, rather than relying solely on primary sources. Primary sources should not be used to advance a particular point of view or to promote original research. For instance, a historical document can be used to state the date of an event, but a historian's analysis of that document should be used to explain its significance. Over-reliance on primary sources can lead to original research, which is prohibited on Wikipedia.