APIs (Application Programming Interfaces) have become increasingly popular in recent years for building and connecting software applications. According to Postman's 2023 State of the API report, APIs are becoming more essential for companies to stay competitive and to provide value to their customers. And as more developers make APIs a core part of their technology stacks, high-quality documentation is essential for smooth API adoption and usage.
Yet, writing effective API documentation presents unique challenges for technical writers. APIs are highly technical by nature, yet the documentation must be accessible to developers with varying levels of experience. Fortunately, there are ways to fulfill this challenge rather successfully.
In this article, let's cover the dos and don'ts of writing API documentation we at ClickHelp have shaped over the years to help technical writers clearly explain what an API does, how to use it, its common integration scenarios, and more.
The Dos
Be concise yet thorough
While covering all relevant information in sufficient detail, you should avoid unnecessary verbosity. Stick to explaining key concepts and workflows simply, clearly, and precisely. Avoid rambling descriptions and redundant information, but don't be too brief. Developers should have all the technical specifics they need without requiring extra steps to fill gaps.
Use simple, clear language
While keeping a necessary amount of technical jargon, API documentation should favor simple language that is easy to understand by most audiences, no matter their levels of expertise and professional background.
Don't shy away from technical details – just present them accessibly and define any terms that may be unfamiliar. Explain your acronyms and abstraction in time.
Structure and organize into logical sections
Effective structure of any document, API documentation included, is key for the reader to quickly find what they need. Break your documentation down into logical sections and categories, and use clear and simple headers, table of contents, and navigation. Maintain a consistent structure across all the documentation you have.
Include code samples and examples
Nothing demonstrates how an API works better than code examples. Provide snippets of sample code in major languages showing how to call the API, pass parameters, and handle responses. Abstract examples are helpful, but actual code eliminates the guesswork. Examples should be complete, well-annotated, and easy to adapt.
Use consistent formatting and naming conventions
Consistent naming and formatting removes ambiguity and makes documentation easier to follow. Establish set conventions for things like endpoints, parameters, data structures, and stick to them across all documentation. Use the same terms and naming patterns throughout.
Keep documentation up-to-date with API changes
Outdated documentation is frustrating and can lead to errors. Have processes in place to update docs whenever APIs change. Use versioning to manage docs for different API iterations. Clearly note deprecations and upcoming changes. Make it easy for developers to find docs for the API version they are using.
Make documentation easy to search and navigate
While working within extensive documentation, it’s very important to be able to quickly find any specific information, so don’t forget to optimize search with tags and indexing. Link related information between sections for easy navigation. Use visual elements like menus, icons, or diagrams so that your documentation is easy for a quick read and navigation.
Provide guidance on authentication and setup
Many APIs require some form of authentication. So, in your API documentation, it should be explained exactly how to get API credentials, register for access, and set up encryption keys. Provide details on authorization flows, OAuth, permissions levels, and domains. Cover prerequisites clearly so developers can get started easily. Even if it seems that the audiences must be quite familiar with authentication systems by default, don’t hold such information back.
Document error handling and responses
Documentation should provide details on all possible API responses, not just successful ones. So cover potential errors thoroughly, with examples of error messaging, troubleshooting tips, and how to handle failures.
Cover various use cases and scenarios
The documentation should demonstrate API capabilities through real-world examples. Provide samples covering the most common use cases and real integration scenarios. Showcase how the API performs with different inputs and configurations and document edge cases and limitations. Don't just focus on happy paths – ensure developers understand how the API handles a wide range of conditions.
Use specific tools to make your documentation better
What’s the best way to have your API documentation clear and structured? To create it with a special tool tailored just for that. Such as ClickHelp.
With ClickHelp, creating API documentation is fast and simple, and it saves you a lot of time and effort. Book a live demo to see for yourself how using ClickHelp can increase your product adoption.
Write documentation with the end user in mind
API documentation shouldn’t be written for some generic technical audience – it should be tailored for the very developers that will use it.
Use familiar language and terminology. Be comprehensive but focus on what developers actually need to be successful. Address common pain points and misunderstandings. Treat docs as a conversation with the audience and guide them accordingly.
The Donts
Don't use overly technical jargon and acronyms
Avoid relying too heavily on niche terminology and jargon. Not all developers will be intimately familiar with API’s processes or abbreviations. Resist the urge to use insider language that may confuse those less familiar with the API's domain. Focus on broadly understandable terms.
Don't assume too much existing knowledge
Don't make assumptions about the reader's preexisting knowledge. Documentation should provide enough background and foundational information for anyone unfamiliar with the API. Explain underlying concepts before diving into details. Link to educational prerequisites.
Don't skimp on details or explanations
Resist the temptation to gloss over complex sections just because they are complicated to document. Developers rely on thorough, nuanced technical explanations. Don't omit important details simply because they require more work and more intricate documentation. Take the time to methodically cover the challenging areas.
Don't have broken links or outdated info
There's nothing more frustrating than documentation links and content that are out of date or simply don’t work. Check regularly for broken links, inaccurate information, or references to previous API versions. Have a clear process for identifying and fixing obsolete documentation. But don't just remove it. Replace with updated info.
Don't document internal implementation details
Avoid oversharing internal logic, code flows, or architecture that don't directly assist the reader. Too much internal documentation can confuse more than explain. Focus documentation on what the audience needs to work with the API, not specifics of how it works behind the scenes. Keep examples centered on usage, not what happens internally.
Don't duplicate information covered elsewhere
Duplication creates maintenance headaches and dilutes the documentation’s usefulness. Stick to value-adding documentation and avoid rehashing the same content across multiple pages when possible. Review regularly for redundancy.
Don't make documentation hard to find on your site
Burying documentation under complex navigation minimizes its value. It should be easily accessible from your developer portal, site navigation, and search. Make access intuitive with contextual linking. Prominently highlight and promote documentation to increase usage.
Don't forget about documentation for mobile apps/devices
Increasingly, APIs are leveraged by mobile developers. Don't overlook their documentation needs. Cover integration guidance for iOS, Android, responsive design, etc. Detail mobile authentication, data usage, and offline considerations. Explaining mobile usage scenarios makes an API more attractive.
Conclusion
Effective API documentation is crucial for adoption and long-term API success. And it’s on technical writers to translate complex APIs for ease of integration. More than explaining how an API technically works, you guide the journey developers take from evaluation to mastery. You provide solutions, not just information.
And ClickHelp is with you every step of the way as an easy and simple yet utterly professional tool for creating, storing, and maintaining API documentation. Book a live demo or sign up for a free trial and see for yourself the ways to make your API documentation better.
Good luck with your technical writing!
ClickHelp Team
Author, host and deliver documentation across platforms and devices