Fin

Fin Authentication API

A modified OAuth 2.0 Client Credential Flow

GitHub OpenAPI

Operations 2

POST /v1/oauth/token Issue a Token #
POST /v1/oauth/refresh-token Refresh a Token #

Documentation

📖
Authentication
https://artifacts.apis.io/fin/authentication/fin-authentication.yml

Specifications

⚙
OpenAPI
https://artifacts.apis.io/fin/openapi/fin-authentication-api-openapi.yml

Other Resources

🔗
Webhooks
https://artifacts.apis.io/fin/asyncapi/fin-webhooks.yml
🔗
ErrorCatalog
https://artifacts.apis.io/fin/errors/fin-problem-types.yml
🔗
Conventions
https://artifacts.apis.io/fin/conventions/fin-conventions.yml
🔗
DataModel
https://artifacts.apis.io/fin/data-model/fin-data-model.yml
🔗
APIsJSON
https://artifacts.apis.io/fin/apis.yml

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OpenAPI Specification

fin-authentication-api-openapi.yml Raw ↑ 
openapi: 3.2.0
info:
  title: Fin Authentication API
  version: 1.0.0
  description: 'Operations tagged Authentication across 2 of this provider''s published API definitions: fin-openapi-original.yml, fin-openapi.yml. Each path carries the servers of the definition it was published in.'
servers:
- url: https://sandbox.api.fin.com
  description: Sandbox server
- url: https://api.fin.com
  description: Production server
tags:
- name: Authentication
  description: A modified OAuth 2.0 Client Credential Flow
paths:
  /v1/oauth/token:
    post:
      summary: Issue a Token
      description: Generate an access token using client credentials
      x-mint:
        content: "Grab your `client_id` and `client_secret` from the\n[API Keys](https://orchestration.fin.com/api-keys) section\nof the [Orchestration Dashboard](https://orchestration.fin.com/)\n\n<Note>\n  The TTLs returned from this API are actually the time\n  that the the token will expire; i.e. not validity in number of seconds\n  since creation.\n</Note>\n\n<Note>\n  The timestamps, i.e. TTLs returned from this endpoint are NOT\n  in ISO 8601 format. Rather it is in the format \n  `YYYY-MM-DD HH:MM:SS+00`\n</Note>\n"
      tags:
      - Authentication
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - client_id
              - client_secret
              properties:
                client_id:
                  type: string
                  description: Client ID
                client_secret:
                  type: string
                  description: Client Secret
                  format: password
      responses:
        '200':
          description: Token issued successfully
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/TokenResponse'
        '401':
          $ref: '#/components/responses/AuthenticationError'
        '422':
          $ref: '#/components/responses/ValidationError'
      operationId: postV1OauthToken
      x-operation-id-source: derived
    servers:
    - url: https://sandbox.api.fin.com
      description: Sandbox server
    - url: https://api.fin.com
      description: Production server
  /v1/oauth/refresh-token:
    post:
      summary: Refresh a Token
      description: Generate a new token pair based on a refresh token.
      x-mint:
        content: "Exchanges a `refresh_token` received from the [Issue Token](/api-reference/authentication/issue-a-token) endpoint for a new\npair of `access_token` and `refresh_token`\n\n<Note>\n  The TTLs returned from this API are actually the time\n  that the the token will expire; i.e. not validity in number of seconds\n  since creation.\n</Note>\n\n<Note>\n  The timestamps, i.e. TTLs returned from this endpoint are NOT\n  in ISO 8601 format. Rather it is in the format \n  `YYYY-MM-DD HH:MM:SS+00`\n</Note>\n"
      tags:
      - Authentication
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - refresh_token
              properties:
                refresh_token:
                  type: string
                  description: The refresh_token received from the [Issue a token](https://developer.fin.com/api-reference/authentication/issue-a-token) endpoint.
      responses:
        '200':
          description: Token issued successfully
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/TokenResponse'
        '401':
          $ref: '#/components/responses/AuthenticationError'
        '422':
          $ref: '#/components/responses/ValidationError'
      operationId: postV1OauthRefreshToken
      x-operation-id-source: derived
    servers:
    - url: https://sandbox.api.fin.com
      description: Sandbox server
    - url: https://api.fin.com
      description: Production server
components:
  schemas:
    TokenResponse:
      type: object
      properties:
        access_token:
          type: string
          example: eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...
        access_token_ttl:
          type: string
          format: date-time
          example: '2025-12-28 10:34:45+00'
        refresh_token:
          type: string
          example: eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...
        refresh_token_ttl:
          type: string
          format: date-time
          example: '2025-12-28 10:34:45+00'
        current_time:
          type: string
          format: date-time
          example: '2025-12-21 10:34:45+00'
    TokenResponse_2:
      type: object
      properties:
        access_token:
          type: string
          description: The access token for API authentication
          example: eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...
        access_token_ttl:
          type: string
          format: date-time
          description: Access token expiration timestamp
          example: '2025-12-28 10:34:45+00'
        refresh_token:
          type: string
          description: The refresh token for obtaining new access tokens
          example: eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...
        refresh_token_ttl:
          type: string
          format: date-time
          description: Refresh token expiration timestamp
          example: '2025-12-28 10:34:45+00'
        current_time:
          type: string
          format: date-time
          description: Current server timestamp
          example: '2025-12-21 10:34:45+00'
  responses:
    ValidationError:
      description: Failed due to a formatting error.
      content:
        application/json:
          schema:
            type: object
            required:
            - message
            properties:
              message:
                type: string
              errors:
                type: array
                items:
                  type: object
                  additionalProperties:
                    type: string
    AuthenticationError:
      description: Authentication failed due to invalid credentials
      content:
        application/json:
          schema:
            type: object
            properties:
              message:
                type: string
                example: Authentication failed
    ValidationError_2:
      description: Failed due to a formatting error.
      content:
        application/json:
          schema:
            type: object
            required:
            - message
            properties:
              message:
                type: string
                description: An error message describing what went wrong.
              errors:
                type: array
                items:
                  type: object
                  additionalProperties:
                    type: string
                    example: Appropriate client_secret required.
    AuthenticationError_2:
      description: Authentication failed due to invalid credentials
      content:
        application/json:
          schema:
            type: object
            properties:
              message:
                type: string
                description: The error message
                example: Authentication failed
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      bearerFormat: JWT
      description: Bearer token authentication. Obtain token from [Issue a Token](https://developer.fin.com/api-reference/authentication/issue-a-token) endpoint
x-refined-from:
- fin-openapi-original.yml
- fin-openapi.yml