> ## Documentation Index
> Fetch the complete documentation index at: https://apidocs.seismic-cards.systems/llms.txt
> Use this file to discover all available pages before exploring further.

# Create or update a spend control



## OpenAPI

````yaml /openapi.json post /v1/cards/spend-controls
openapi: 3.1.0
info:
  title: Seismic Card Issuance API
  version: 1.0.0
  description: >-
    The Seismic Card Issuance API is the integration surface for issuing and
    managing cards. Authenticate with your Seismic API key, onboard applicants,
    run KYC, and issue virtual or physical cards — all through one white-labeled
    API.
  contact:
    name: Seismic Support
    url: https://seismic.systems
servers:
  - url: https://api.seismic-cards.systems
    description: Production
  - url: http://localhost:4000
    description: Local development
security:
  - bearerAuth: []
tags:
  - name: Authentication
    description: Exchange Seismic API keys for a short-lived access token.
  - name: Applicants
    description: End-users and businesses, plus their identity verification (KYC).
  - name: KYC
    description: >-
      Identity verification settings, hosted sessions, BYOK share tokens, and
      issuer readiness.
    x-group: Identity verification (KYC)
  - name: Accounts
    description: Funding accounts that back issued cards.
  - name: Cardholders
    description: Approved applicants turned into cardholders.
  - name: Cards
    description: Issue and manage virtual and physical cards.
  - name: Transactions
    description: Card transaction history from the issuer or local ledger.
  - name: Widget SDK
    description: >-
      Public Seismic-hosted Widget.js for Method 1 card reveal (no auth).
      PAN/CVV render inside PCI iframes.
  - name: Card funding
    description: >-
      Fund prepaid cards with stablecoins: Seismic wallet service or
      bring-your-own (BYO) external wallet.
paths:
  /v1/cards/spend-controls:
    post:
      tags:
        - Cards
      summary: Create or update a spend control
      operationId: createCardsSpendControls
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
                - applicant_id
                - usage
                - keywords
                - list_type
              properties:
                applicant_id:
                  type: string
                usage:
                  type: string
                  enum:
                    - MCC
                    - SCENARIO
                    - TRANSACTION_CURRENCY
                keywords:
                  type: string
                  description: 4-digit MCC, 3-letter currency code, or scenario substring.
                list_type:
                  type: string
                  enum:
                    - BLACKLIST
                    - WHITELIST
                id:
                  type: integer
                  description: Issuer control id when updating an existing rule.
                card_ids:
                  type: array
                  items:
                    type: string
                card_bin_ids:
                  type: array
                  items:
                    type: string
            example:
              applicant_id: app_abc123
              usage: MCC
              keywords: '5812'
              list_type: BLACKLIST
      responses:
        '200':
          description: Spend control saved.
          content:
            application/json:
              schema:
                type: object
                properties:
                  data:
                    type: object
                    additionalProperties: true
              example:
                data:
                  id: 1
                  usage: MCC
                  keywords: '5812'
                  list_type: BLACKLIST
components:
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      bearerFormat: JWT
      description: >-
        Bearer access token obtained from `POST /v1/oauth/token` using your
        Seismic API key.

````