---
title: "Retrieves a specific feature flag by key."
method: GET
path: "/v1/sdk/flags/{key}"
tags: ["Server SDK"]
---

# Retrieves a specific feature flag by key.

`GET /v1/sdk/flags/{key}`

## Request

- Base URL: `https://eval.featureflip.io`
- URL: `https://eval.featureflip.io/v1/sdk/flags/{key}`
- Auth: API key in header `Authorization`

## Path parameters

- `key` string, required

## Response `200`

Returns the flag configuration.

- FlagDto
  - `key` string, nullable, required
  - `version` integer, required
  - `type` 'Boolean' | 'String' | 'Number' | 'Json', required
  - `enabled` boolean, required
  - `variations` VariationDto[], nullable, required
    - `key` string, nullable, required
    - `value` unknown, required
  - `rules` RuleDto[], nullable, required
    - `id` string, nullable, required
    - `priority` integer, required
    - `conditionGroups` ConditionGroupDto[], nullable, required
      - `operator` 'And' | 'Or', required
      - `conditions` ConditionDto[], nullable, required
        - `attribute` string, nullable, required
        - `operator` 'Equals' | 'NotEquals' | 'Contains' | 'NotContains' | 'StartsWith' | 'EndsWith' | 'In' | 'NotIn' | 'MatchesRegex' | 'GreaterThan' | 'LessThan' | 'GreaterThanOrEqual' | 'LessThanOrEqual' | 'Before' | 'After' | 'SemverEquals' | 'SemverGreaterThan' | 'SemverGreaterThanOrEqual' | 'SemverLessThan' | 'SemverLessThanOrEqual', required
        - `values` string[], nullable, required
        - `negate` boolean
    - `serve` ServeConfigDto, required
      - `type` 'Fixed' | 'Rollout', required
      - `variation` string, nullable
      - `bucketBy` string, nullable
      - `salt` string, nullable
      - `variations` WeightedVariationDto[], nullable
        - `key` string, nullable, required
        - `weight` integer, required
    - `segmentKey` string, nullable
  - `fallthrough` ServeConfigDto, required
    - `type` 'Fixed' | 'Rollout', required
    - `variation` string, nullable
    - `bucketBy` string, nullable
    - `salt` string, nullable
    - `variations` WeightedVariationDto[], nullable
      - `key` string, nullable, required
      - `weight` integer, required
  - `offVariation` string, nullable, required
  - `prerequisites` PrerequisiteDto[], nullable, required
    - `prerequisiteFlagKey` string, nullable, required
    - `expectedVariationKey` string, nullable, required

## Other responses

- `401`: SDK key is missing or invalid.
- `404`: Flag with the specified key was not found.
- `503`: Flag configuration is temporarily unavailable; retry after the interval in `Retry-After`.

---

[API](https://skmtc.dev/featureflip/apis/featureflip-evaluation-api.md) · [All operations](https://skmtc.dev/featureflip/apis/featureflip-evaluation-api/llms.txt) · [OpenAPI document](https://skmtc.dev/featureflip/apis/featureflip-evaluation-api/revisions/1f5311d7fc25?raw)