Liquid Tags Introduction

Tags are the logic of a template. They are written between {% and %} and print nothing themselves. Use them to assign variables, make decisions, repeat content, run GraphQL and render partials.

Example

insites-cli exec liquid docs57 "{% assign user = 'Adam' %}{% if user %}Hello {{ user }}!{% endif %}"
Hello Adam!

This ran on the docs.insites.io instance on 1 November 2026. The assign and if tags print nothing; only the text inside the if appears.

The kinds of tag

Many tags in one block

The liquid tag lets you write several tags without repeating the delimiters, one tag per line:

{% liquid
  assign name = 'Adam'
  if name
    echo 'Hello ' | append: name
  endif
%}

Tags only Insites has

Some tags exist only on Insites, because they talk to the instance. graphql runs a query or mutation and stores the result in a variable. redirect_to sends the visitor to another address. log writes a value to the instance log, which you follow with insites-cli logs. background runs a partial as a background job, so slow work does not hold up the page.

Add a hyphen inside the delimiters, as in {%- if -%}, to remove the spaces and line breaks around a tag. See Whitespace control.

Common mistakes

• Expecting a variable set inside an include to come back to the caller. Use function and return to get a value back.
• Putting two tags on one line inside a liquid block. Each tag needs its own line.
• Using the form tag. Use a plain HTML form with the CSRF token.

• Insites tagsTags only Insites has.
• Whitespace controlTrim spaces around tags.