ChatGPT, developed by OpenAI, is being explored as a tool to modernize APIs by creating OpenAPI specifications for existing APIs with documentation. This effort aims to address challenges faced by legacy APIs, such as lack of standardized documentation and versioning, which can hinder maintenance and adoption. OpenAPI specifications, defined by the OpenAPI Initiative, offer a standardized, machine-readable format that enhances consistency, allows for documentation and versioning, and facilitates quicker development and adoption of APIs. In the context of this exploration, the API "Where the ISS at?" which provides data about the International Space Station, is used as a case study. The documentation for this API is accessible via the Wayback Machine in case the main site becomes unavailable. The full details of the ChatGPT interactions for generating an OpenAPI specification can be found on GitHub, illustrating how ChatGPT can streamline the process of updating API documentation to meet modern standards.