Quality Application Programming Interface (API) documentation makes a significant impact on product success. The purpose of API documentation is to communicate what an API does and how to use it both internally and externally. Across industries, API documentation is used as both a reference for software testing and for technical documentation. Without quality API documentation, developers won’t be able to connect with your API securely and easily.

Consider your API documentation as an interface between your application or organization and all the developers at other organizations trying to use it. It’s critical to ensure the API documentation you produce is accurate, up-to-date, and understandable for developers. A recent developer survey reported that accurate and detailed API documentation was more important than any other factor for developers selecting an API.

This guide describes what API documentation is, what it includes, and how it impacts overall product success.

Key Takeaways

  • What is API documentation?
  • What are the best practices for API documentation?
  • Discover how quality API documentation impacts product and project success.

What is API documentation?

API documentation defines the purpose of an API, how to connect with it, and how to use the services the API provides. Most API documentation contains an overview of the purpose and services, as well as examples, tutorials, and functional coding details for endpoints, authentication, and coding. Everything a developer needs to create successful API integrations and calls should exist in your API documentation.

High-quality API documentation enhances the developer experience, which is important because it determines how many potential users actually use the API. The happier the developer, the more likely they’ll return and use other products. Aside from external developers, API documentation assists in training internal development staff and conducting quality API testing.

When API documentation is solid, there’s no need for development or support team members to spend time helping users connect with the API. The more external users can connect on their own, the more resource time is saved and the more costs are reduced.

What are the best practices for API documentation?

API documentation best practices include:

  • API overview or outline. Set expectations and hook potential users with the capabilities of the API
  • Authentication requirements. Describe authentication and security schemes
  • Endpoint definitions. Include all the endpoints the API interacts with and include the URL per service
  • Status and error codes. Include descriptions for all status and error code values, as well as instructions on resolving errors
  • HTTP request information. Include full descriptions of all endpoints and connection methods
  • Examples and tutorials. Provide tested examples of successful calls, responses, error handling, and any other operations users may encounter when using the API. Tutorials or video presentations walking the user through connecting to the API are also valuable for end-user education

Creating valid documentation for your API enhances the developer experience. The more popular your API product is with developers, the higher your brand and organization’s reputation for producing quality products.

Impact of API documentation quality on product success

Application development businesses understand the importance of user experience in attracting new customers and retaining existing ones. Developer experience is no different. By providing quality API documentation, the business increases developer loyalty and potential use for existing and future products.