Grafana Alloy is the new name for our distribution of the OTel collector. Grafana Agent has been deprecated and is in Long-Term Support (LTS) through October 31, 2025. Grafana Agent will reach an End-of-Life (EOL) on November 1, 2025. Read more about why we recommend migrating to Grafana Alloy.

Important: This documentation is about an older version. It's relevant only to the release noted, many of the features and functions have been updated or replaced. Please view the current version.

Open source


coalesce takes any number of arguments and returns the first one that isn’t null, an empty string, empty list, or an empty object. It is useful for obtaining a default value, such as if an environment variable isn’t defined. If no argument is non-empty or non-zero, the last argument is returned.


> coalesce("a", "b")
> coalesce("", "b")
> coalesce(env("DOES_NOT_EXIST"), "c")