Federico Esteban contributed to the GenericMappingTools/pygmt repository by enhancing the documentation for the Figure.coast function, specifically clarifying that the 'shorelines' parameter accepts boolean values. He focused on aligning the API documentation with the actual behavior of the Python bindings, ensuring that users have a clearer understanding of parameter types without introducing any functional changes. Federico utilized his skills in Python and technical documentation to improve API clarity, which helps reduce user confusion and streamlines onboarding for new contributors. His work emphasized accuracy and traceability, supporting smoother releases and minimizing the need for additional support or clarification.