Apiary vs Doxygen

Apiary is a hosted web platform for designing, documenting, prototyping, and testing APIs. Its editor supports API Blueprint and OpenAPI (Swagger), with instant validation and a live preview as descriptions are written. Publishing a description creates a mock server that returns the responses specified in it; the default limit is 120 requests per minute, or 5,000 with authentication. Automated tests compare real API responses with expectations generated from the description. Apiary also supports OpenAPI import, interactive references, code samples, and API versioning. Teams can manage document access with Admin, Editor, and Viewer roles, and sync with GitHub. Branch-based GitHub integration is available on Pro. The free plan costs nothing and permits unlimited API projects and five participants per project, but projects are public and teams are not included. Standard and Pro are deprecated, with plan changes handled by support request for current customers. Embedding interactive documentation is supported on Standard and Pro.

Doxygen is a free documentation generator that turns source-code comments into reference material, parsing items such as classes, functions and variables. It supports C/C++, Lex, Java, Python, VHDL, PHP IDL, C#, Fortran, Objective-C 2.0 and some D sources. Output can be generated as HTML, PDF through LaTeX, Word through RTF or structured XML for external tools. Graphviz’s dot tool can add include-dependency, collaboration, call, directory-structure and class-hierarchy diagrams. Doxywizard provides a graphical interface for editing settings and running the generator on Windows, Linux and macOS; Doxygen also works on many Unix flavors. It supports HTML Help, docsets, Qt-Help and Eclipse Help, with more than 100 configurable options. The tool runs without registration and does not collect personal or usage data. It is self-hosted and licensed under the GNU General Public License, without express or implied warranty. Help is listed through Stack Overflow and the doxygen users mailing list; commercial feature and bug-fix support has limited capacity.