There are several variables available for you to use in your build steps:

$ASSET_DIR The filepath which contains any assets you uploaded to your Probo project.
$BRANCH_NAME The name of the branch the build is based on.
$BRANCH_LINK An HTML link to the branch (in Github, Bitbucket, etc).
$BUILD_ID The ID for the build.
$BUILD_DOMAIN The HTTPS URL of the build.
$COMMIT_REF The commit ID the build is based on.
$COMMIT_LINK An HTML link to the commit (in Github, Bitbucket, etc).
$PROBO_ENVIRONMENT Boolean acknowledging the build is in Probo.
$PULL_REQUEST_NAME The name of the Pull Request.
$PULL_REQUEST_LINK An HTML link to the pull request (in Github, Bitbucket, etc).
$SRC_DIR The filepath which contains the code from your pull request.
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