Flags Endpoint

Get all flags

Fetches the complete flag configuration for the authenticated environment. SDKs typically call this once during initialization and then keep the data in memory.

GET /flags

Response

{
  "environment": "env-abc123",
  "version": 42,
  "flags": [
    {
      "key": "dark-mode",
      "version": 3,
      "type": "Boolean",
      "enabled": true,
      "variations": [
        { "key": "on", "value": true },
        { "key": "off", "value": false }
      ],
      "rules": [],
      "fallthrough": {
        "type": "Fixed",
        "variation": "on"
      },
      "offVariation": "off"
    }
  ],
  "segments": [
    {
      "key": "beta-testers",
      "version": 1,
      "conditions": [
        {
          "attribute": "plan",
          "operator": "In",
          "values": ["pro", "enterprise"],
          "negate": false
        }
      ],
      "conditionLogic": "And"
    }
  ]
}

Response fields

Field	Type	Description
environment	string	Environment identifier for the SDK key
version	int	Configuration version (increments on any change)
flags	FlagDto[]	All flags in this environment
segments	SegmentDto[]	All segments (referenced by targeting rules)

---

Get a single flag

Fetches the configuration for one flag by its key.

GET /flags/{key}

Path parameters

Parameter	Type	Description
key	string	The flag key

Response

Returns a single FlagDto object (see data types below). Returns 404 if the flag does not exist.

---

Data types

FlagDto

Field	Type	Description
key	string	Unique flag identifier
version	int	Flag configuration version
type	string	"Boolean", "String", "Number", or "Json"
enabled	bool	Whether the flag is on in this environment
variations	VariationDto[]	All possible return values
rules	RuleDto[]	Targeting rules, evaluated in priority order
fallthrough	ServeConfigDto	What to serve when the flag is on and no rules match
offVariation	string	Variation key returned when the flag is off

VariationDto

Field	Type	Description
key	string	Variation identifier
value	any	The value (boolean, string, number, or JSON object)

RuleDto

Field	Type	Description
id	string	Rule identifier
priority	int	Execution order (lower = evaluated first)
conditions	ConditionDto[]	Conditions to evaluate
conditionLogic	string	"And" (all must match) or "Or" (any must match)
serve	ServeConfigDto	What to serve if the rule matches
segmentKey	string?	Segment key if the rule targets a segment

ConditionDto

Field	Type	Description
attribute	string	Context attribute to check (e.g., "userId", "country")
operator	string	Comparison operator (see below)
values	string[]	Values to compare against
negate	bool	Invert the condition result

Condition operators: Equals, NotEquals, Contains, NotContains, StartsWith, EndsWith, In, NotIn, MatchesRegex, GreaterThan, LessThan, GreaterThanOrEqual, LessThanOrEqual, Before, After

ServeConfigDto

Field	Type	Description
type	string	"Fixed" or "Rollout"
variation	string?	Variation key (when type is Fixed)
bucketBy	string?	Attribute to hash for rollout bucketing
salt	string?	Hash salt for consistent bucketing
variations	WeightedVariationDto[]?	Weighted variations (when type is Rollout)

WeightedVariationDto

Field	Type	Description
key	string	Variation identifier
weight	int	Percentage weight (0—100, must sum to 100 across all entries)

SegmentDto

Field	Type	Description
key	string	Segment identifier
version	int	Configuration version
conditions	ConditionDto[]	Conditions that define segment membership
conditionLogic	string	"And" or "Or"

See also

• API Overview — authentication, rate limiting, and all endpoints
• Evaluate Endpoint — evaluate flags for user contexts
• Streaming Endpoint — receive real-time flag.updated events
• Targeting & Segments — understand rules, conditions, and segments
• SDK Overview — official SDKs fetch and cache flags automatically