Blend

Blend Borrowers & Parties API

Borrowers, coborrowers, realtors, employers, incomes, and positions.

Documentation GitHub OpenAPI

Business capability

Credit Origination Management BC-1320.10

Operations 6

GET /applications/{id}/parties List parties for an application #

POST /applications/{id}/parties Add a party (coborrower, etc.) to an application #

PATCH /applications/{id}/parties/{partyId} Update a party #

DELETE /applications/{id}/parties/{partyId} Remove a party #

GET /applications/{id}/borrower-positions Get borrower positions #

PUT /applications/{id}/borrower-positions Set borrower positions #

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OpenAPI Specification

openapi: 3.2.0
info:
  title: Blend Public Borrowers & Parties API
  description: The Blend Public API is the documented REST surface of the Blend Labs digital lending and account-opening platform (developers.blend.com).
  version: 12.0.0
  contact:
    name: Blend Labs
    url: https://developers.blend.com/blend
  termsOfService: https://blend.com/legal/terms-of-service/
servers:
- url: https://api.blendlabs.com
  description: Production
- url: https://api.beta.blendlabs.com
  description: Beta / integration environment (used in Blend's documentation examples)
security:
- bearerAuth: []
tags:
- name: Borrowers & Parties
  description: Borrowers, coborrowers, realtors, employers, incomes, and positions.
paths:
  /applications/{id}/parties:
    parameters:
    - $ref: '#/components/parameters/ApplicationId'
    get:
      operationId: listParties
      tags:
      - Borrowers & Parties
      summary: List parties for an application
      responses:
        '200':
          description: The parties on the application.
          content:
            application/json:
              schema:
                type: object
                properties:
                  data:
                    type: array
                    items:
                      $ref: '#/components/schemas/Party'
    post:
      operationId: createParty
      tags:
      - Borrowers & Parties
      summary: Add a party (coborrower, etc.) to an application
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/PartyInput'
      responses:
        '201':
          description: The created party.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Party'
  /applications/{id}/parties/{partyId}:
    parameters:
    - $ref: '#/components/parameters/ApplicationId'
    - $ref: '#/components/parameters/PartyId'
    patch:
      operationId: patchParty
      tags:
      - Borrowers & Parties
      summary: Update a party
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/PartyInput'
      responses:
        '200':
          description: The updated party.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Party'
    delete:
      operationId: deleteParty
      tags:
      - Borrowers & Parties
      summary: Remove a party
      responses:
        '204':
          description: Removed.
  /applications/{id}/borrower-positions:
    parameters:
    - $ref: '#/components/parameters/ApplicationId'
    get:
      operationId: getBorrowerPositions
      tags:
      - Borrowers & Parties
      summary: Get borrower positions
      responses:
        '200':
          description: Borrower positions.
    put:
      operationId: putBorrowerPositions
      tags:
      - Borrowers & Parties
      summary: Set borrower positions
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
      responses:
        '200':
          description: Updated borrower positions.
components:
  schemas:
    PartyInput:
      type: object
      properties:
        name:
          type: object
          properties:
            firstName:
              type: string
            lastName:
              type: string
        email:
          type: string
          format: email
        role:
          type: string
    Party:
      type: object
      properties:
        id:
          type: string
        name:
          type: object
          properties:
            firstName:
              type: string
            lastName:
              type: string
        email:
          type: string
          format: email
        econsent:
          type: string
  parameters:
    PartyId:
      name: partyId
      in: path
      required: true
      schema:
        type: string
      description: The party ID.
    ApplicationId:
      name: id
      in: path
      required: true
      schema:
        type: string
      description: The application ID.
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      bearerFormat: JWT
      description: Blend authenticates requests with an authorization Bearer token. Each call must also send blend-api-version (to pin the API version) and blend-target-instance (tenant~instance) headers. API Secret Keys are exchanged for short-lived, request-scoped JWTs at Blend's API Gateway. Credentials are issued to Blend customers and certified partners - contact your Blend account team or partnerships to obtain them.