Greenboard - Generate beautiful static api documentation
Dr.Explain - Dr.Explain software is a help file authoring tool.
ThinkJS - use full ES6/7 features to develop web applications
MadCap Flare - Documentation for Any Audience, Language or Format
SpectaQL - Autogenerate static GraphQL API documentation
HelpNDoc - What is HelpNDoc ? Easy to use yet powerful help authoring environment which can generate various documentation formats from a single source.