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Source: Roblox Creator Hub · CC BY 4.0 · View source · Code samples: MIT Imported 2026-10-03. Formatting adapted for this site.

POST /v1/passkey/start-authentication-by-user — openapi

Initializes passkey authentication for the user(s) corresponding to the identifier provided.

Endpoint

Method: POST

Path: /v1/passkey/start-authentication-by-user

Servers:

• https://auth.roblox.com

Request Body

{
  "content": {
    "application/json": {
      "schema": {
        "$ref": "#/components/schemas/Roblox.Authentication.Api.Models.Request.StartAuthenticationByUserRequest"
      }
    },
    "text/json": {
      "schema": {
        "$ref": "#/components/schemas/Roblox.Authentication.Api.Models.Request.StartAuthenticationByUserRequest"
      }
    }
  },
  "required": true
}

Responses

{
  "200": {
    "description": "OK",
    "content": {
      "application/json": {
        "schema": {
          "$ref": "#/components/schemas/Roblox.Authentication.Api.Models.Response.StartAuthenticationByUserResponse"
        }
      },
      "text/json": {
        "schema": {
          "$ref": "#/components/schemas/Roblox.Authentication.Api.Models.Response.StartAuthenticationByUserResponse"
        }
      }
    }
  },
  "400": {
    "description": "5: User identifier and type are required.\r\n6: Multi-user passkey authentication is not supported for this credential type."
  },
  "403": {
    "description": "0: Token Validation Failed\r\n4: No passkeys registered for any users found."
  },
  "503": {
    "description": "2: Feature disabled."
  }
}

Authentication

{
  "security": [
    {}
  ],
  "securitySchemes": {
    "roblox-api-key": {
      "type": "apiKey",
      "description": "A configurable key that allows granular access to Roblox resources. See https://create.roblox.com/docs/cloud/auth/api-keys for more information.",
      "name": "x-api-key",
      "in": "header"
    },
    "roblox-legacy-cookie": {
      "type": "apiKey",
      "description": "A browser cookie that represents the identity of a Roblox user. DO NOT SHARE THIS. Sharing this will allow someone to log in as you and to steal your Robux and items. We do not recommend using cookies to call endpoints. When possible, use API keys with the x-api-key header or OAuth 2.0 instead for authentication.",
      "in": "cookie",
      "name": ".ROBLOSECURITY"
    },
    "roblox-oauth2": {
      "type": "oauth2",
      "description": "Build or authorize apps to access Roblox resources. See https://create.roblox.com/docs/cloud/auth/oauth2-overview for more information.",
      "flows": {
        "authorizationCode": {
          "authorizationUrl": "https://apis.roblox.com/oauth/v1/authorize",
          "tokenUrl": "https://apis.roblox.com/oauth/v1/token",
          "refreshUrl": "https://apis.roblox.com/oauth/v1/token",
          "scopes": {}
        }
      }
    }
  }
}

Related Schemas

• Roblox.Authentication.Api.Models.Request.StartAuthenticationByUserRequest

• Roblox.Authentication.Api.Models.Response.StartAuthenticationByUserResponse

Complete Operation Definition

{
  "tags": [
    "Accounts"
  ],
  "summary": "Initializes passkey authentication for the user(s) corresponding to the identifier provided.",
  "requestBody": {
    "content": {
      "application/json": {
        "schema": {
          "$ref": "#/components/schemas/Roblox.Authentication.Api.Models.Request.StartAuthenticationByUserRequest"
        }
      },
      "text/json": {
        "schema": {
          "$ref": "#/components/schemas/Roblox.Authentication.Api.Models.Request.StartAuthenticationByUserRequest"
        }
      }
    },
    "required": true
  },
  "responses": {
    "200": {
      "description": "OK",
      "content": {
        "application/json": {
          "schema": {
            "$ref": "#/components/schemas/Roblox.Authentication.Api.Models.Response.StartAuthenticationByUserResponse"
          }
        },
        "text/json": {
          "schema": {
            "$ref": "#/components/schemas/Roblox.Authentication.Api.Models.Response.StartAuthenticationByUserResponse"
          }
        }
      }
    },
    "400": {
      "description": "5: User identifier and type are required.\r\n6: Multi-user passkey authentication is not supported for this credential type."
    },
    "403": {
      "description": "0: Token Validation Failed\r\n4: No passkeys registered for any users found."
    },
    "503": {
      "description": "2: Feature disabled."
    }
  },
  "servers": [
    {
      "url": "https://auth.roblox.com"
    }
  ],
  "x-roblox-engine-usability": {
    "apiKeyWithHttpService": false
  },
  "security": [
    {}
  ],
  "externalDocs": {
    "url": "https://create.roblox.com/docs/cloud/reference/features/accounts#auth_post_v1_passkey_start_authentication_by_user"
  }
}