Label

The label action allows Mergify to automatically add or remove labels from a pull request based on the conditions specified in your rules, making your workflow more organized and efficient.

pull_request_rules:
  - name: add "WIP" label when the title contains "WIP"
    conditions:
      - title ~= WIP
    actions:
      label:
        toggle:
          - WIP

In this example, Mergify will automatically add the “WIP” label to any pull request whose title contains “WIP”. If the pull request does not match the rule anymore, the label will be removed.

When browsing the list of pull request, GitHub does not give any indication on which pull requests might be in conflict. Mergify allows to do this easily by adding a label.

pull_request_rules:
  - name: warn on conflicts
    conditions:
      - conflict
    actions:
      comment:
        message: "@{{author}} this pull request is now in conflict 😩"
      label:
        toggle:
          - conflict

Then, your pull request list will look like this on conflict:

This rule toggle a label based on the failure status of a CI system.

pull_request_rules:
  - name: toggle labels based on CI state
    conditions:
      - check-failure = CI
    actions:
      label:
        toggle:
          - "CI:fail"

This rule add a label with the name of the branch.

pull_request_rules:
  - name: add a label with the name of the branch
    conditions: []
    actions:
      label:
        add:
          - "branch:{{base}}"