Style guide

Language

The Kong docs use American English (US English). There are some spelling, grammar, and vocabulary differences between American English and other varieties.

Here are some examples:

✅ Do use (American English)	❌ Don’t use (other variations)
The response should look like…	The response shall look like…
In the previous section, you learned…	In the previous section, you learnt…
Color, recognize, analyze	Colour, recognise, analyse
While	Whilst

Voice and tone

Write for people, not computers. You are human, Kong’s users are human – let’s write for each other.

At Kong, we try to keep our tone conversational, but not at the expense of clarity. We keep language simple and concise, take things seriously when we need to, and keep our readers in mind in whatever we write.

Here are some examples of parallel conversational and formal terms and phrasing:

✅ Do use	❌ Don’t use
Run the program.	Execute the program.
Use the Admin API.	Utilize the Admin API.
Open the link to do the thing.	Open the link in order to do the thing.
In the open tab, do the thing.	In the open tab that appears, do the thing. In the open tab that displays, do the thing.
Clearly refer to subjects. For example, say “Once you have added the inputs section, …”	Avoid generic pronouns. For example, don’t say “Once you have added this, …”

Active voice

Use active voice, and avoid passive voice.

With active voice, the subject performs an action. With passive voice, the action is being performed upon the subject:

✅ Active	❌ Passive
The plugin applies rate limiting to consumers.	Rate limits are applied to consumers by the plugin.
You can explore the API using a browser.	The API can be explored using a browser.
The YAML file specifies the replica count.	The replica count is specified in the YAML file.

There are exceptions to this guideline. You might use passive voice to communicate that the subject is passive and is having something done to it.

For example: “The CA provider’s external account can be registered automatically”. In this sentence, the account is passive and isn’t doing anything, so you can use passive voice.

Present tense

Whenever possible, use present tense instead of past or future.

✅ Do use	❌ Don’t use
This `command` starts a proxy.	This `command` will start a proxy.
This `command` starts a proxy.	This `command` has started a proxy.

Contractions

Don’t be afraid to use contractions (can’t, isn’t, you’ll, and so on)! It adds to the conversational tone.

As with everything, there are exceptions to the rule. You can omit contractions when aiming for a more serious tone, typically to emphasize a warning or caution.

For example, you might use a contraction in a phrase like “This plugin isn’t available in Konnect” to let a reader know about plugin availability. On the other hand, you might say “Do not use this plugin in Konnect because it will break things” to warn them about potential consequences.

Latin phrases

Don’t use Latin phrases or short forms. Use the english version of the same phrase.

✅ Do use	❌ Don’t use
For example, …	e.g., …
That is, …	i.e., …
So (or therefore), …	Ergo, …

Recommendations

Recommendations should have a reason. If you’re recommending an approach, explain why.

A recommendation should apply to most users. It’s not a suggestion. For example, we wouldn’t recommend DB-less mode without context, but we could recommend it in a specific use case that explains why.

When recommending a course of action, use the phrase “we recommend”.

✅ Do use	❌ Don’t use
We recommend using an access token because it’s more secure.	Kong recommends using an access token.
We don’t recommend storing a password in plaintext because it’s not secure.	It is recommended that you use an access token.

Grammar and syntax

Punctuation rules

Commas and periods always go inside quotation marks, and colons, semicolons, and dashes go outside.

For example: “There was a storm last night,” Paul said.

List punctuation

✅ Do use punctuation when constructing lists that contain full sentences:

In DB-less mode, you configure Kong Gateway declaratively. Therefore, the Admin API is mostly read-only. The only tasks it can perform are all related to handling the declarative configuration, including:

Setting a target’s health status in the load balancer.

Validating configurations against schemas.

Uploading the declarative configuration using the /config endpoint.

❌ Don’t use punctuation when creating ordered and unordered lists that are extensions of a sentence:

Kong Mesh enables the microservices transformation with:

Out-of-the-box service connectivity and discovery

Zero-trust security

Traffic reliability

Global observability across all traffic

Headings and page titles

When writing section headings or page titles, be descriptive. What is someone going to do in this section, or on this page? If it’s an overview, what is it an overview of?

For example:

✅ Do use	❌ Don’t use
Kong Gateway Overview	Overview
Improve Vitals performance with InfluxDB	InfluxDB
Query frequency and precision	Query behavior

Use sentence case for section headings. For example:

✅ Do use	❌ Don’t use
Understanding traffic flow in Kong Gateway	Understanding Traffic Flow in Kong Gateway
Get started with the Request Transformer Advanced plugin	Get Started with the Request Transformer Advanced Plugin

Capitalization

When documenting a user interface (UI), follow its formatting. If a term is capitalized in the UI and you are referring to the specific UI element, it should be capitalized in the documentation.

Don’t capitalize the following terms:

application
certificate
consumer
control plane
database
data plane
developer
hybrid mode
plugin
route
service
service mesh
target
upstream

Plugin name capitalization

Capitalize the plugin name but not the word plugin. For example, “Rate Limiting plugin”.
Don’t capitalize the name if you’re using it in code. For example, rate-limiting.
Don’t capitalize if you’re referring to the concept, not the plugin. For example, “Set up rate limiting in Kong Gateway with the Rate Limiting plugin”.

Kong-specific term capitalization

For product and component names, see Word Choice.

Object/entity names (for example, service, route, upstream) should be lowercase.

Formatting

Automatic formatting

Prettier is used to format all prose and code files. There are three ways to meet this standard:

Install the Prettier plugin for your editor
Run npx prettier --write ./your/edited/files.md in the terminal
(Maintainers only) Add the ci:autofix:prettier label to a Pull Request

All files in app/_src are formatted with Prettier. Prose in app has not been bulk-formatted and may be formatted as you edit those files.

Content types

At Kong, we use the four following standard content types when we write our documentation:

Explanation: Documentation that is understanding-oriented because it clarifies and discusses a particular topic.
How-to: Documentation that is goal-oriented and prescriptive and that takes readers through the steps to complete a real-world problem.
Reference: Documentation that explains the technology, like API or command line documentation.
Tutorial: Documentation that helps users learn about a topic by going step-by-step through a series of tasks.

Every documentation page should fit one of these four content types.

Placeholder and example values

The type of placeholder you use depends on context:

Generic placeholder values: In most situations (such as plugin parameters, YAML examples, or Kong configuration), use all caps text and underscores between words.

For example: service: SERVICE_NAME
Placeholders in API URLs or OpenAPI specs: Enclose placeholders in { } characters and write them in all caps, per Swagger guidelines.

For example: /services/{SERVICE_NAME|ID}/plugins
Hostnames and example URLs:
- For guides with examples that are intended to be runnable as-is, use localhost as the domain name.
  
  For example: curl -i -X https://localhost:8001/services
  
  If you are following a guide where Kong Gateway is running on localhost, this example can be copied and pasted straight into a terminal. It should work with no changes.
- For situations where you need a generic domain name and the examples are illustrative only (not intended to be runnable as-is), use example or example.com.
  
  For example: user@example.com or https://example.okta.admin.com
Path parameters
- Path parameters must be denoted with curly braces {}.
  
  For example: http://localhost:8001/services/{service_id_or_name}/routes/{route_id_or_name}

Inline placeholders

If you’re adding a placeholder inline, such as in a sentence, enclose it in single backticks: `EXAMPLE_TEXT`

Code formatting

Separate commands from output.
Include properly formatted code comments.
For long commands, split the code block into separate lines with \ to avoid horizontal scrolling.
Never have more than one command in a block/example.
Set a language for code blocks, for example, bash, to enable syntax highlighting.
- List of supported languages
Do NOT use the command prompt marker ($) in code snippets.

Icons

When deciding which icon to use for a doc, use the following guidelines:

Is there a Unicode version?

We use Unicode for common icons such as ✅ and ❌ . You can copy and paste a Unicode icon directly into markdown.
Is there a Font Awesome icon?

We also use the free version of Font Awesome to supplement Unicode icons. Check out their catalog to find an icon code, then see our icon usage instructions.
Does the /_assets/images/icons/ folder contain the icon that you’re looking for?

For custom icons, we have to import them manually. This includes all of the icons used in docs navigation and all icons that are used for UI labels in Konnect and Kong’s UIs. If you find one, see our icon usage instructions.
If the answer to all of the above is “no”, you can upload a custom image.

Documenting third-party tools

Our documentation sometimes requires integration with third-party tools and services to help users succeed with our products. As a general rule, we try to avoid rewriting docs that exist elsewhere. When writing docs that involve interactions with third-party tools and services, think about the following:

Does the third-party app have a complete doc in their own documentation that covers the process?
Does the process include a lot of custom configuration of the third-party product to get it to work with Kong?
Do you need to switch back and forth between Kong and the third-party to complete a task?

Depending on your answers, you should:

Link to third-party documentation: Always link to the official documentation of third-party products. In many cases, a link is enough, often as part of a step or a group of prerequisites. Here’s a doc that uses this method:
- Add Developer Teams from Identity Providers
Include third-party instructions with integrations: Provide instructions that involve switching between products, and include links to the official third-party documentation when possible. For example:
- How to configure Transit Gateways

Pitfalls to avoid

To reduce maintenance challenges when documenting third-party instructions, avoid the following:

Do not include screenshots of third-party UIs.
Do not refer to specific UI elements:
- ❌ Don’t use: “Click the blue Add button in the top-right corner.”
- ✅ Use: “Click Add.”
Describe the necessary variables, but do not specify their location in the UI:
- ❌ Don’t use: “Enter the API key found in the Security tab under API Settings.”
- ✅ Use: “Enter the API key provided by your API provider.”

Links

Write descriptive titles that make it clear what the reader is getting by clicking the link. Don’t use link titles like “Read more” and “Click here”:

✅ Do use	❌ Don’t use
For more information, see the style guide.	For more information, click here.
Learn about content best practices in the Kong style guide.	Learn about content best practices here.

If the linked content is a larger area like a panel, add a title attribute that describes the linked content to the a tag.

Reference style guide

Follow Kong’s style guide whenever possible. However, we recommend using the Google developer style guide for style and formatting cases that our guide doesn’t cover.