One top contender is ReadMe, which converts static API documentation into interactive, up-to-the-minute developer centers. It's got OpenAPI synchronization, a Try It API GraphQL playground, and a range of other tools like guides, code samples and API logs. It's highly customizable, and offers a range of pricing plans to suit different needs.
Another strong contender is ReAPI, which accelerates API design, testing and documentation with AI-powered tools. It's got a visual API designer based on OpenAPI and supports GraphQL, so you can design and manage APIs more easily. ReAPI also offers automated documentation, collaboration tools and a no-code test case designer, all designed to make developers more productive.
If you're looking for a cloud API platform that lets you generate REST and GraphQL APIs immediately, Neurelo is worth a look. It supports multiple databases and offers features like Schema as Code, AI-powered custom query APIs and deep query observability. That can significantly ease database programming tasks and help developers get more done.