Worked on improving the accuracy of documentation in the segmentio/segment-docs repository, focusing on aligning identity resolution guides with current product capabilities. Addressed a documentation bug by removing the deprecated 'groupId' from the list of promoted identifiers, ensuring that the documentation no longer referenced outdated features. Updated two Markdown files to reflect these changes, using Markdown as the primary language and applying strong documentation skills to clarify technical details. The work aimed to reduce developer confusion and support requests by maintaining documentation parity with the product, demonstrating attention to detail and a methodical approach to technical writing and documentation maintenance.