semantic-conventions/docs/attributes-registry/feature-flag.md

Feature flag

• Feature Flag Attributes
• Deprecated Feature Flag Attributes

Feature Flag Attributes

This document defines attributes for Feature Flags.

Attribute	Type	Description	Examples	Stability
feature_flag.context.id	string	The unique identifier for the flag evaluation context. For example, the targeting key.	5157782b-2203-4c80-a857-dbbd5e7761db
feature_flag.key	string	The lookup key of the feature flag.	logo-color
feature_flag.provider.name	string	Identifies the feature flag provider.	Flag Manager
feature_flag.result.reason	string	The reason code which shows how a feature flag value was determined.	static; targeting_match; error; default
feature_flag.result.variant	string	A semantic identifier for an evaluated flag value. [1]	red; true; on
feature_flag.set.id	string	The identifier of the flag set to which the feature flag belongs.	proj-1; ab98sgs; service1/dev
feature_flag.version	string	The version of the ruleset used during the evaluation. This may be any stable value which uniquely identifies the ruleset.	1; 01ABCDEF

[1] feature_flag.result.variant: A semantic identifier, commonly referred to as a variant, provides a means for referring to a value without including the value itself. This can provide additional context for understanding the meaning behind a value. For example, the variant red maybe be used for the value #c05543.

---

feature_flag.result.reason has the following list of well-known values. If one of them applies, then the respective value MUST be used; otherwise, a custom value MAY be used.

Value	Description	Stability
cached	The resolved value was retrieved from cache.
default	The resolved value fell back to a pre-configured value (no dynamic evaluation occurred or dynamic evaluation yielded no result).
disabled	The resolved value was the result of the flag being disabled in the management system.
error	The resolved value was the result of an error.
split	The resolved value was the result of pseudorandom assignment.
stale	The resolved value is non-authoritative or possibly out of date
static	The resolved value is static (no dynamic evaluation).
targeting_match	The resolved value was the result of a dynamic evaluation, such as a rule or specific user-targeting.
unknown	The reason for the resolved value could not be determined.

Deprecated Feature Flag Attributes

Describes deprecated feature flag attributes.

Attribute	Type	Description	Examples	Stability
feature_flag.evaluation.error.message	string	Deprecated, use error.message instead.	Flag header-colorexpected typestringbut found typenumber``	Replaced by error.message.
feature_flag.evaluation.reason	string	Deprecated, use feature_flag.result.reason instead.	static; targeting_match; error; default	Replaced by feature_flag.result.reason.
feature_flag.provider_name	string	Deprecated, use feature_flag.provider.name instead.	Flag Manager	Replaced by feature_flag.provider.name.
feature_flag.variant	string	Deprecated, use feature_flag.result.variant instead.	red; true; on	Replaced by feature_flag.result.variant.

---

feature_flag.evaluation.reason has the following list of well-known values. If one of them applies, then the respective value MUST be used; otherwise, a custom value MAY be used.

Value	Description	Stability
cached	The resolved value was retrieved from cache.
default	The resolved value fell back to a pre-configured value (no dynamic evaluation occurred or dynamic evaluation yielded no result).
disabled	The resolved value was the result of the flag being disabled in the management system.
error	The resolved value was the result of an error.
split	The resolved value was the result of pseudorandom assignment.
stale	The resolved value is non-authoritative or possibly out of date
static	The resolved value is static (no dynamic evaluation).
targeting_match	The resolved value was the result of a dynamic evaluation, such as a rule or specific user-targeting.
unknown	The reason for the resolved value could not be determined.