Swagger is an open source software framework backed by a large ecosystem of tools that helps developers design, build, document, and consume RESTful Web services.
You can embed swagger API doc in any kinds of projects(Node, PHP, etc…).
For example, you can user swagger-express-ui and swagger-jsdoc packages in express.js backend project.
Also, there is public swagger UI html project online. You can simply embed this project as project assets
If you want, you can embed swagger editor on your project, too. Please download html editor and keep it on your assets directory.