Worked on enhancing the Messaging API within the intercom/Intercom-OpenAPI repository, focusing on improving API expressiveness and documentation quality. Delivered a feature that introduced CC and BCC support, along with multi-recipient capabilities, by refactoring the To field to handle both users and leads. This update, implemented using YAML and leveraging OpenAPI Specification, aimed to increase integration flexibility and streamline message composition for clients. The work centered on updating API documentation to clearly reflect these changes, aligning with business goals to improve developer experience. No critical bugs were addressed during this period, with primary efforts dedicated to feature development and documentation.