Swagger is an open-source tool that enables the creation, design, documentation, and usage of RESTful APIs. It has components such as the swagger editor, which allows users to write a specification on OpenAPI, and the swagger user interface, which turns the OpenAPI specifications into interactive API documentation. The swagger Codegen uses client libraries from OpenAPI specification to create server stubs. DapperDox enhances the use and quality of API documentation by providing multiple themes, integrating APIs with an inbuilt API explorer, and allowing users to adjust guides and incorporate API specifications. ReDoc is a tool that allows users to create API specifications while offering expert advisory services on building these specifications, and it has a Reactjs component integrated into react projects easily. The OpenAPI Generator is known for its easy-to-use interface and can build documentation for OAS 2.0 and 3.0 documents, supporting multiple client generators and being highly extensible. It also shows different document formats and allows users to generate server stubs for different languages using the OpenAPI Generator. Good API documentation should explain API calls, provide software development kits examples, offer programming language examples, include a user manual with authentic data and sample requests and responses, and have elements that make it easy to use and navigate. Documentation tools such as Swagger, DapperDox, ReDoc, and OpenAPI Generator can save time and energy for developers, improve the client's experience, and earn companies a good reputation by automating the API documentation process.