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


Expressions represent or compute values that can be assigned to attributes within a configuration.

Basic expressions are literal values, like "Hello, world!" or true. Expressions may also do things like refer to values exported by components, perform arithmetic, or call functions.

Expressions can be used when configuring any component. As all component arguments have an underlying type, River will type-check expressions before assigning the result to an attribute.