Worked on the rust-lang/rust repository to enhance documentation for the core find() and rfind() APIs, focusing on clarity and consistency for end users. Improved the documentation by adding missing usage examples and aligning example formats, ensuring that both functions present scenarios in a uniform manner. Utilized Rust and documentation tooling to deliver these changes, emphasizing content accuracy and precise changelog updates. The work aimed to provide clearer API guidance, streamline onboarding for new contributors, and reduce the risk of misusage in the core library. No bug fixes were required, as the primary focus was on documentation quality and usability improvements.