Feature flag evaluate API

Resolves a feature flag by walking ordered JsonLogic targeting rules against a context and returning the first matching value, else the default, with which rule served it. Answers 'Is this flag on for this user?', 'Which flag variant should I serve?'.

Price$0.02per request

MethodPOST

Route/v1/workflow/feature-flag

StatusLive

MIME typeapplication/json

Rate limit120/minute

Cache0s public

feature-flagflagtargetingrollouttogglejsonlogicexperimentworkflow

API URLhttps://x402.hexl.dev/v1/workflow/feature-flag

Integration docs

Example request

{
  "flagKey": "new-ui",
  "rules": [
    {
      "when": {
        "==": [
          {
            "var": "plan"
          },
          "pro"
        ]
      },
      "value": true
    }
  ],
  "default": false,
  "context": {
    "plan": "pro"
  }
}

Example response

{
  "flagKey": "new-ui",
  "value": true,
  "matchedRule": 0,
  "usedDefault": false,
  "interpretation": "Flag 'new-ui' served by rule 0 -> true."
}

Input schema

{
  "type": "object",
  "required": [
    "flagKey",
    "default"
  ],
  "properties": {
    "flagKey": {
      "type": "string",
      "examples": [
        "new-ui"
      ]
    },
    "rules": {
      "type": "array",
      "examples": [
        [
          {
            "when": {
              "==": [
                {
                  "var": "plan"
                },
                "pro"
              ]
            },
            "value": true
          }
        ]
      ]
    },
    "default": {
      "examples": [
        false
      ]
    },
    "context": {
      "type": "object",
      "examples": [
        {
          "plan": "pro"
        }
      ]
    }
  }
}

Output schema

{
  "type": "object",
  "additionalProperties": true
}