Telegraf, an open-source plugin-driven agent for collecting, processing, aggregating, and writing time series data, has introduced a new feature in v1.27 that enables users to filter metrics using the Common Expression Language (CEL). This allows users to reference specific components of a metric, such as its name, tags, fields, or timestamp values, to determine which metrics should be passed on or dropped. The CEL language provides a set of semantics for expression evaluation and supports logical operators, numeric operations, string operations, and time operations, making it easier for users to filter metrics with specific names, tags, fields, or timestamp values. This new feature aims to improve the performance and flexibility of Telegraf's metric filtering capabilities.