Vincent Foulon updated the DataHandler UID format documentation in the TYPO3-Documentation/TYPO3CMS-Reference-CoreApi repository, clarifying that category UIDs should be provided as a comma-separated string rather than an array. He focused on aligning the documentation with the actual implementation, reducing integration errors and improving onboarding for developers. Using reStructuredText and technical writing skills, Vincent ensured the guidance for tt_content.categories accurately reflected input expectations, referencing specific commit history for traceability. His work demonstrated attention to detail in documentation authoring and Git-based collaboration, resulting in clearer API documentation and more consistent integration practices for the TYPO3 developer community.