Documentation Style Guide

This style guide is adapted from the Kubernetes style guide.

This page outlines writing style guidelines for the Harbor documentation and you should use it as a reference as you write or edit content. These are guidelines, not rules. Use your best judgment as you write documentation, and feel free to propose changes to these guidelines.

Changes to the style guide are made by the Harbor maintainers as a group. To propose a change or addition create an issue/PR, or come to a community meeting to discuss your suggestions.

The Harbor documentation uses the Goldmark Markdown renderer.

Content best practices

Use present tense

Do and Don't - Use present tense
Do Don’t
This command starts a proxy. This command will start a proxy.

Exception: Use future or past tense if it is required to convey the correct meaning.

Use active voice

Do and Don't - Use active voice
Do Don’t
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.

Exception: Use passive voice if active voice leads to an awkward sentence construction.

Use simple and direct language

Use simple and direct language. Avoid using unnecessary phrases, such as saying “please.”

Do and Don't - Use simple and direct language
Do Don’t
To create a ReplicaSet, … In order to create a ReplicaSet, …
See the configuration file. Please see the configuration file.
View the Pods. With this next command, we’ll view the Pods.

Address the reader as “you”

Do and Don't - Addressing the reader
Do Don’t
You can create a Deployment by … We’ll create a Deployment by …
In the preceding output, you can see… In the preceding output, we can see …

Avoid Latin phrases

Prefer English terms over Latin abbreviations.

Do and Don't - Avoid Latin phrases
Do Don’t
For example, … e.g., …
That is, … i.e., …

Exception: Use “etc.” for et cetera.

Patterns to avoid

Avoid using “we”

Using “we” in a sentence can be confusing, because the reader might not know whether they’re part of the “we” you’re describing.

Do and Don't - Avoid using we
Do Don’t
Version 1.4 includes … In version 1.4, we have added …
Kubernetes provides a new feature for … We provide a new feature …
This page teaches you how to use Pods. In this page, we are going to learn about Pods.

Avoid jargon and idioms

Many readers speak English as a second language. Avoid jargon and idioms to help them understand better.

Do and Don't - Avoid jargon and idioms
Do Don’t
Internally, … Under the hood, …
Create a new cluster. Turn up a new cluster.

Avoid statements about the future or that will soon be out of date

Avoid making promises or giving hints about the future. If you need to talk about a beta feature, put the text under a heading that identifies it as beta information.

Also avoid words like “recently”, “currently” and “new.” A feature that is new today might not be considered new in a few months.

Do and Don't - Avoid statements that will soon be out of date
Do Don’t
In version 1.4, … In the current version, …
The Federation feature provides … The new Federation feature provides …


This documentation uses U.S. English spelling and grammar.

Documentation formatting standards

Use angle brackets for placeholders

Use angle brackets for placeholders. Tell the reader what a placeholder represents.

  1. Display information about a Pod:

     kubectl describe pod <pod-name> -n <namespace>

    If the pod is in the default namespace, you can omit the ‘-n’ parameter.

Use bold for user interface elements

Do and Don't - Bold interface elements
Do Don’t
Click Fork. Click “Fork”.
Select Other. Select “Other”.

Use code style for filenames, directories, paths, object field names and namespaces

Do and Don't - Use code style for filenames, directories, paths, object field names and namespaces
Do Don’t
Open the envars.yaml file. Open the envars.yaml file.
Go to the /docs/tutorials directory. Go to the /docs/tutorials directory.
Open the /_data/concepts.yaml file. Open the /_data/concepts.yaml file.

Use punctuation inside quotes

Do and Don't - Use code style for filenames, directories, paths, object field names and namespaces
Do Don’t
events are recorded with an associated “stage.” events are recorded with an associated “stage”.
The copy is called a “fork.” The copy is called a “fork”.

Exception: When the quoted word is a user input.


  • My user ID is “IM47g”.
  • Did you try the password “mycatisawesome”?

Inline code formatting

Use code style for inline code and commands

For inline code in an HTML document, use the <code> tag. In a Markdown document, use the backtick (`).

Do and Don't - Use code style for filenames, directories, paths, object field names and namespaces
Do Don’t
The kubectl run command creates a Deployment. The “kubectl run” command creates a Deployment.
For declarative management, use kubectl apply. For declarative management, use “kubectl apply”.
Use single backticks to enclose inline code. For example, var example = true. Use two asterisks (**) or an underscore (_) to enclose inline code. For example, var example = true.
Use triple backticks (```) before and after a multi-line block of code for fenced code blocks. Use multi-line blocks of code to create diagrams, flowcharts, or other illustrations.
Use meaningful variable names that have a context. Use variable names such as ‘foo’,‘bar’, and ‘baz’ that are not meaningful and lack context.
Remove trailing spaces in the code. Add trailing spaces in the code, where these are important, because a screen reader will read out the spaces as well.

Use normal style for string and integer field values

For field values of type string or integer, use normal style without quotation marks.

Do and Don't - Use normal style for string and integer field values
Do Don’t
Set the value of imagePullPolicy to Always. Set the value of imagePullPolicy to “Always”.
Set the value of image to nginx:1.16. Set the value of image to nginx:1.16.
Set the value of the replicas field to 2. Set the value of the replicas field to 2.

Code snippet formatting

Don’t include the command prompt

Do and Don't - Don't include the command prompt
Do Don’t
kubectl get pods $ kubectl get pods

Separate commands from output

Verify that the Pod is running on your chosen node:

kubectl get pods --output=wide

The output is similar to this:

NAME     READY     STATUS    RESTARTS   AGE    IP           NODE
nginx    1/1       Running   0          13s   worker0

Harbor word list

A list of Harbor-specific terms and words to be used consistently across the site.

Harbor word list
Trem Usage
Kubernetes Kubernetes should always be capitalized.
Harbor Harbor should always be capitalized.
Docker Docker should always be capitalized.
Allowlist Use allowlist instead of whitelist.
Denylist Use denylist instead of blacklist.

Markdown elements


People accessing this documentation may use a screen reader or other assistive technology (AT). Screen readers are linear output devices, they output items on a page one at a time. If there is a lot of content on a page, you can use headings to give the page an internal structure. A good page structure helps all readers to easily navigate the page or filter topics of interest.

Do and Don't - Headings
Do Don’t
Include a title on each page or blog post. Include more than one title headings (#) in a page.
Use ordered headings to provide a meaningful high-level outline of your content. Use headings level 4 through 6, unless it is absolutely necessary. If your content is that detailed, it may need to be broken into separate articles.
Use title case for headings. For example, Extend Kubectl With Plugins Use sentence case for headings. For example, Extend kubectl with plugins


Do and Don't - Paragraphs
Do Don’t
Try to keep paragraphs under 6 sentences. Write long-winded paragraphs.
Use three hyphens (---) to create a horizontal rule for breaks in paragraph content. Use horizontal rules for decoration.
Do and Don't - Links
Do Don’t
Write hyperlinks that give you context for the content they link to. For example: Certain ports are open on your machines. See check required ports for more details. Use ambiguous terms such as “click here”. For example: Certain ports are open on your machines. See here for more details.
Write Markdown-style links: [link text](URL). For example: [community meeting agenda]( and the output is community meeting agenda. Write HTML-style links: <a href="/media/examples/link-element-example.css" target="_blank">Visit our tutorial!</a>


Group items in a list that are related to each other and need to appear in a specific order or to indicate a correlation between multiple items. When a screen reader comes across a list—whether it is an ordered or unordered list—it will be announced to the user that there is a group of list items. The user can then use the arrow keys to move up and down between the various items in the list. Website navigation links can also be marked up as list items; after all they are nothing but a group of related links.

  • End each item in a list with a period if one or more items in the list are complete sentences. For the sake of consistency, normally either all items or none should be complete sentences.

  • Ordered lists that are part of an incomplete introductory sentence can be in lowercase and punctuated as if each item was a part of the introductory sentence.

  • Use the number one (1.) for ordered lists.

  • Use (+), (*), or (-) for unordered lists - be consistent within the same document.

  • Leave a blank line after each list.

  • Indent nested lists with four spaces (for example, ⋅⋅⋅⋅).

  • List items may consist of multiple paragraphs. Each subsequent paragraph in a list item must be indented by either four spaces or one tab.


The semantic purpose of a data table is to present tabular data. Sighted users can quickly scan the table but a screen reader goes through line by line. A table caption is used to create a descriptive title for a data table. Assistive technologies (AT) use the HTML table caption element to identify the table contents to the user within the page structure.

If you need to create a table, create the table in markdown and use the table Hugo shortcode to include a caption.

{{< table caption="Configuration parameters" >}}
Parameter | Description | Default
`timeout` | The timeout for requests | `30s`
`logLevel` | The log level for log output | `INFO`
{{< /table >}}

Note: This shortcode does not support markdown reference-style links. Use inline-style links in tables. See more information about markdown link styles.