6 Best Practices for API Documentation

Previously, we discussed the top 5 best practices in technical writing. In this blog, we will be taking a step ahead to discuss API documentation and its 6 best practices.

First, let me give you a brief introduction about APIs and why it is important to document them.

Applications are responsible for taking information from the various user interfaces (UIs), performing calculations and transactions on the database layer, and then presenting the results back to the user interface. However, in addition to this, applications must be able to communicate directly with each other. For example, your mobile ride-sharing application will need to communicate with the mapping service, the traffic and weather services, and other specialized applications used by the drivers providing the rides. In the modern, interconnected world, all these different systems can interact with each other seamlessly using APIs.

It is certainly difficult to develop the API without knowing which endpoint to use and how, nearly none to poor supporting documentation makes it even more difficult to even fix a bug because the source is unknown.

Here are the best practices that you can follow while preparing the API document:

1. Easy to Read & Search

The document hierarchy describes the structure of the documents that your application is designed to process. Your document must contain a list of available APIs in production followed by the methods supported by the API and their workings such as –

Once the document structure has been simplified, it would be easier to search for anything across it.

2. Test Before You Write

When looking at an API testing tool, it is important to understand which API technologies you will be using and the best way to test them. Nowadays most APIs you come across will be of the Web Service variety (either REST or SOAP), but you may come across other technologies such as Java EJBs or Microsoft DCOM/ActiveX DLLs as well.

So before writing, understand how it works by getting in touch with your team members and ensure that you have the right knowledge which will make it simpler for you to present it to your viewers.

Check for API testing tools within your project and get hands-on on it. This way you make sure that the document is true to its content and learn new concepts and explore your perspectives.

Below are some basic questions that you should be able to answer:

• What endpoints are available?
• What HTTP verbs can be used with those endpoints?
• Are any of the verbs limited by authorization?
• Which parameters are required in the requests?
• What are the validation limits on the parameters?
• What response codes should be expected for a successful request?
• What response codes should be expected for an unsuccessful request?
• What sort of error messages will be returned in the body of an unsuccessful request?

3. Release Notifications

Release and pre-release/upcoming notes are for both support and marketing. Keep a separate page/section for them.

Sharing release notes regularly sets the right expectations and keeps the users informed. Keep the release notes brief, mention the release date and version, and provide a hyperlink to the API section where the actual change is made.

Sharing the pre-release notes helps users plan for their next move depending on the release. Keep the pre-release brief with a UAT screenshot and expected release date (optional).

4. Give Code Examples

Developers strongly rely on API reference information and code examples. Providing interactive demos or sample codes of Request body and Response body is a powerful way to improve the learning curve of consuming your API.

For each endpoint they can view the supportable parameters’ format which answers:

• What are the parameters required to run the API?
• What response body should be expected for a successful request?
• What response error message should be expected for an unsuccessful request?
• What changes should be made to the request body to handle the error?

5. Support API with the related UI Process

If UI is for humans who interact with the face of a software, API is for programmers who interact with it behind the scenes to make the software functional. So, for non-technical visitors, it would be a great idea to explain the user interface experience that is related to the API.

For example, for Employee API, describing how to create an employee record from frontend application will simplify the understanding of the associate API request and response body. Supporting the API execution with user interface steps will motivate the user to keep scrolling through the document.

6. Use Utility to Reduce Time

Despite being practiced by a few, this method has a good impact on the documentation cycle. From a broader perspective, API is going to be present for the long run.

So, for a  lengthier webpage document, you can also consider automating the documentation format. Now you only have to copy-paste your content in the utility and it will take care of the structure and view of the page. You can also have your utility switch between different code formats automatically on a click.

You can search for such utilities on the internet or get them developed by the right product development company, which will further reduce your documentation time and formatting burden.

We hope that the above practices will make your journey to writing great API documentation easier and fulfilling.

Contact us if you have any questions about API documentation or write to us at Nitor Infotech if you would like to know more about other services that we have to offer.