API documentation is critical for providing a positive developer experience. A popular API equals happy devs. In other words, Application Programming Interfaces (APIs) are only as good as their api docs. If you have a wonderful API but don’t give detailed API documentation on how to utilize it, it’s all for naught.
API Documentation in a Nutshell
API documentation is written text (or reference manual) that accompanies an API. API documentation explains how to effectively use the API. API documentation can is created manually or automatically using API documentation software.
APIs are meant to be consumed. As a result, it is critical to guarantee that users can begin adopting them immediately and without difficulty. Unfortunately, most APIs are inadequately documented, making integration harder and defeating the point of their existence.
In this article, we’ll learn the best practices for writing API docs. These guidelines are crucial to know if you want your APIs to be easy and user-friendly enough that developers will actually use them.
Table of Contents
- 1 API Documentation in a Nutshell
- 2 What is API documentation?
- 3 Why is API documentation important?
- 4 Best Practices for Documenting APIs
- 5 Conclusion
What is API documentation?
API documentation is a reference document that outlines how to use the API. It’s a technical manual that contains information about the services the API offers, how to use its various endpoints and parameters, and other implementation instructions. API document is part of the API Management process. A good API documentation policy also helps in API governance.
APIs allow developers to transmit data between software products easily. With an API, you can fetch the features of a product and integrate them into your application, without the need of starting from scratch.
With good API documentation, developers can understand the usage of an API and incorporate it into their use cases without experiencing programming obstacles.
There are three types of API documentation: reference, tutorial, and conceptual. Reference documentation provides information about the structure, parameters, and return values for each function or method in an API. Tutorials provide step-by-step instructions for using APIs to accomplish specific tasks or workflows with detailed explanations about using the endpoints and parameters in each function call or method invocation. Conceptual documentation provides information about using APIs to build applications rather than just describing what each function does individually; it also includes details on integrating multiple APIs into a single application (e.g., explaining functions that work together).
Types of API Documentation
There are three types of API documentation: reference, tutorial, and conceptual.
Reference documentation provides information about the structure, parameters, and return values for each function or method in an API.
Tutorials provide step-by-step instructions for using APIs to accomplish specific tasks or workflows with detailed explanations about using the endpoints and parameters in each function call or method invocation.
Conceptual documentation provides information about using APIs to build applications rather than just describing what each function does individually; it also includes details on integrating multiple APIs into a single application (e.g., explaining functions that work together).
Why is API documentation important?
API documentation is key to enhancing the developer experience. Developers tend to be very demanding people and they are unlikely to spend countless hours trying to get started implementing your inconsistent and incoherent API.
If you get your API documentation right, many developers will find it easy to use, leading to increased adoption of your products and services.
APIs can greatly assist in the digital transformation efforts of most businesses. Clear API documentation makes it easy for businesses to adopt your API.
Furthermore, well-explained documentation saves support time and costs. With good documentation, your team is likely to spend less time onboarding new users and responding to support calls and emails.
Improperly written REST API documentation template implies that more frustrated users will depend on your team to assist them in integrating your API, which increases your operational costs.
Best Practices for Documenting APIs
Here are 5 of the best practices on how to write API documentation:
- Plan for your docs
- Include fundamental sections
- Be consistent and avoid jargon
- Include interactive examples and other resources
- Maintain your docs
Let’s now talk about each of the ways on how to document an API.
1. Plan for your docs
“Failing to plan is planning to fail,” so goes the famous quote. Definitely, if you fail to plan ahead for your documentation exercise, then you may not be successful with it.
Before embarking on documenting REST API, you should know who you are creating the docs for. If you know the audience your writing will address, it’ll assist you to decide on the language, structure, and design of your documentation.
Who visits your sample API documentation web page?
What do they intend to use it for?
Understanding the purpose and scope of your documentation will help you to craft useful content that enhances the consumption of your API. Creating your API document with user experience in mind allows you to structure it in a manner that addresses their needs.
After all, they’re the people who are going to read it. So, the best way to document REST APIs is to understand users’ needs.
2. Include fundamental sections
There are sections that have become necessary to authoring great API documentation. These fundamental sections are essential for enhancing the readability and adoption of your API. You can tailor them based on the needs you want to address with your documentation.
Here are some of the most pivotal sections in any API documentation template:
- Overview: Including an overview section assists in conveying what your API is about quickly. This opening section can be vital in introducing the user onboarding process and detailing the pertinent attributes of your API. If you can show users a quick win in this section, you’ll have grabbed their attention to continue reading through the rest of the API reference documentation. For example, here’s how AccuWeather does it:
- Authentication: APIs that require authentication need to have a section that clearly explains how to get the access credentials and how the keys work for making requests. Since authentication is one of the initial biggest obstacles to the successful consumption of your API, you need to get it right—the first time.
- Resources: The resources section forms the core component of your API doc. Since users are likely to interact more with your API’s resources, and their corresponding requests and responses, it’s important to provide all the necessary information about them. All endpoints, parameters, and other details should be properly documented.
- Error messages: If you offer useful, human-readable information about the possible error messages a user may encounter when interacting with your API—besides just correct error codes—you’ll allow users to learn and integrate your technology easily. You should also include explanations on how the errors can be solved.
3. Be consistent and avoid jargon
Another best practice for writing API docs is to maintain consistency in the use of terminology throughout your documentation. Your write-up should be entirely uniform and without contradictions in language and code. You should sufficiently proofread your documentation to eliminate sections that are ambiguous or difficult to understand.
It is also important to be consistent with universally accepted naming conventions and terminologies. Whereas you have the freedom to decide on what goes into your code, trying to be excessively creative on the use of status codes, HTTP verbs, and other conventional item names may lead to unnecessary confusion.
For example, when writing a REST API documentation, the GET HTTP verb should always be utilized to retrieve data from a stated resource. Sticking to such well-established conventions will save you the hassle of writing many explanations, making your documentation easier to understand.
Furthermore, you should keep the docs free from unnecessary technical jargon, as much as possible. Your technical writing team may be tempted to use complicated or domain-based jargon; however, it’s in your best interest to use a language that is simple and resonates with the needs of your users.
Assuming that your audience is completely technical and understands how APIs work is a big mistake. Good documentation should be easily understood by people new to the API economy.
If there is technical or domain-based jargon, you can provide links to further documentation that explain their meanings. Remember that humans are the primary readers of your API reference documentation and not machines.
4. Include interactive examples and other resources
More than anything, most developers like it when they can test what they read in the documentation and see how it works. If you can include interactive sample codes in the most popular programming languages, it can greatly reduce the friction in implementing your API.
Providing interactive demos is a powerful way to improve the learning curve of consuming your API. For example, you can include a sandbox environment filled with test data so that users can run requests and see the types of responses returned.
For example, the Deezer API allows you to test its endpoints and get responses right away.
Here is its screenshot:
Furthermore, you can supercharge your API reference documentation by adding other useful resources. This extra information and resources can help users to make the most of your API—beyond the provided documentation. With the best API documentation tool, you can add the materials easily.
Here are some resources you can use to supplement your API document:
- Getting started guide: Including a guide as a quick way to show users how to get started in fetching the features of your API can greatly assist in its adoption. Users are likely to get interested in your offerings after they’ve tried and experienced initial success with how the API works.
- SDKs, libraries, and tutorials: These additional resources can offer step-by-step walkthroughs about how developers can integrate the API in various scenarios while using their most comfortable programming language. Having code libraries and SDKs is an awesome method to engage with developers and enhance API adoption.
5. Maintain API Docs
Ensuring your docs remain accurate and up-to-date is critical for its success. If your API descriptions are obsolete, users can get frustrated and lose trust in your services.
Here are some things you can do to maintain your API docs:
- Remove descriptions of deprecated features. If a feature has been removed from your API, take it from the documentation and explain the reasons behind the decision.
- In case any new feature has been introduced into the API, ensure it’s properly and timely documented. You can also version the API documentation to reflect the newly added features.
- In case you get any feedback, act on it appropriately to improve the quality of your API reference docs. You may not get your documentation right at the first try, but if you listen to feedback, you can continuously make improvements to it.
Knowing how to write API documentation is not a walk in the park. Creating excellent API reference documentation requires hard work and commitment.
However, if you can put in the hours, you can craft awesome documentation that can spearhead the growth and adoption of your APIs.
We hope that the above best practices will make your journey to writing great documentation easier and fulfilling.
All the best.
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