Contributed to the eslint/eslint repository by delivering comprehensive documentation for RuleTester’s global assertion options. Focused on JavaScript and ESLint, the work outlined two distinct customization approaches, clarifying how to enforce assertionOptions in userland patterns. This documentation update addressed repository issue #20986, providing clear guidance to reduce misconfigurations and streamline developer onboarding. The approach emphasized documentation hygiene and commit discipline, ensuring traceability and maintainability. By enhancing the RuleTester usage guide, the contribution supported ongoing documentation modernization efforts and aimed to minimize support follow-ups. The work demonstrated attention to detail in technical writing and a methodical approach to open source collaboration.