docs/data/reusables/webhooks/installation_properties.md

Key	Type	Description
action	string	The action that was performed. Can be one of: created - Someone installs a {% data variables.product.prodname_github_app %}. deleted - Someone uninstalls a {% data variables.product.prodname_github_app %} suspend - Someone suspends a {% data variables.product.prodname_github_app %} installation. unsuspend - Someone unsuspends a {% data variables.product.prodname_github_app %} installation. new_permissions_accepted - Someone accepts new permissions for a {% data variables.product.prodname_github_app %} installation. When a {% data variables.product.prodname_github_app %} owner requests new permissions, the person who installed the {% data variables.product.prodname_github_app %} must accept the new permissions request.
repositories	array	An array of repository objects that the installation can access.