About Trace and Span Attributes
The trace (root span) and span attributes in Trace Explorer are defined by tagging a span, which enable the effective monitoring of the various tiers of an application.
Attributes are key-value pairs attached to a span to provide additional information and context about the operation performed in the span. A trace has some trace only attributes as well as all the span attributes of the root span.
In Trace Explorer, you can use attributes to query and filter traces and spans. There are two types of attributes: Dimensions (string attributes) and Metrics (numeric attributes) which are available in the Attributes panel in Trace Explorer.
This section provides a complete list of the out-of-the-box attributes for the following data sources: