openapi: 3.0.3 info: title: Lithic 3DS Card Authorizations API description: The Lithic API is a card issuing and issuer-processor platform for issuing virtual and physical cards, authorizing and clearing transactions, moving money across ledgered financial accounts, and managing the full card lifecycle - KYC/KYB account holder onboarding, authorization rules and real-time Auth Stream Access (ASA) decisioning, disputes, tokenization into digital wallets, 3DS authentication, ACH payments, book transfers, external payments, settlement reporting, and fraud/transaction monitoring. This document curates the real, published Lithic OpenAPI 3.1 definitions (https://github.com/lithic-com/lithic-openapi) into the endpoint surface referenced by this apis.yml, expressed as OpenAPI 3.0.3 with lightweight response schemas. Requests are authenticated with an API key sent as the raw value of the Authorization header (not a Bearer token). version: 1.0.0 contact: name: Lithic url: https://www.lithic.com license: name: Apache 2.0 url: https://www.apache.org/licenses/LICENSE-2.0.txt servers: - url: https://api.lithic.com description: Production - url: https://sandbox.lithic.com description: Sandbox (mirrors production functionality) security: - ApiKeyAuth: [] tags: - name: Card Authorizations description: Responses to real-time authorization challenges. paths: /v1/card_authorizations/{event_token}/challenge_response: post: operationId: respondToAuthorizationChallenge tags: - Card Authorizations summary: Respond to Authorization Challenge description: Card program's response to Authorization Challenge. Programs that have Authorization Challenges configured as Out of Band receive a [card_authorization.challenge](https://docs.lithic.com/reference/post_card-authorization-challenge) webhook when an authorization attempt triggers a challenge. The card parameters: - name: event_token in: path required: true description: Globally unique identifier for the authorization event that triggered the challenge schema: type: string requestBody: required: true content: application/json: schema: type: object additionalProperties: true responses: '200': description: Successful response. content: application/json: schema: $ref: '#/components/schemas/CardAuthorizations' '401': $ref: '#/components/responses/Unauthorized' '422': $ref: '#/components/responses/ValidationError' components: responses: ValidationError: description: The request failed validation. Unauthorized: description: Missing or invalid API key. schemas: CardAuthorizations: type: object description: Responses to real-time authorization challenges. properties: token: type: string format: uuid description: Globally unique identifier for the object. created: type: string format: date-time additionalProperties: true securitySchemes: ApiKeyAuth: type: apiKey in: header name: Authorization description: Raw API secret key value (not prefixed with "Bearer").