Added by using a description key in the YAML schema. It can be applied to:

Doc Block

You can also provide richer docs using a doc block. Define a .md file within models/ and include your docs. It looks something like this:

{% docs <doc-block-name> %}
...
{% enddocs %}

This can then later be referenced using a string containing jinja:

# In your models/**/*.yml
models:
  ...
    description: '{{ doc("<doc-block-name>") }}'

Command

dbt docs generate