---
title: "EP-20 — Schemes"
url: "https://dev.ionova.ai/apis/ars-address-resolution-service-4/versions/fdd2c316-7f84-4f04-8bb7-64e9bf97893b/operations/getSchemes"
---

> Full API specification: https://dev.ionova.ai/apis/ars-address-resolution-service-4/versions/fdd2c316-7f84-4f04-8bb7-64e9bf97893b.md

# EP-20 — Schemes

`GET` `/schemes`

Operation ID: `getSchemes`

Returns all 11 payment schemes supported by ARS v4.3. No request body. Cache aggressively.

## Header parameters

- `X-Request-ID` (string, uuid, optional) - Client-supplied correlation ID echoed in response headers for tracing.

## Responses

- `200` - Scheme list returned
- `401` - Unauthorized — missing or invalid authentication credentials.
- `500` - Internal Server Error — unexpected server-side failure.

## OpenAPI definition

```yaml
openapi: 3.0.3
info:
  title: ARS — Address Resolution Service
  version: 4.3.1
servers:
  - url: https://api-uat.ionova.ai/ars
    description: UAT (test data only)
paths:
  /schemes:
    get:
      tags:
        - Layer 4 — Reference
      summary: EP-20 — Schemes
      description: Returns all 11 payment schemes supported by ARS v4.3. No request
        body. Cache aggressively.
      operationId: getSchemes
      parameters:
        - $ref: "#/components/parameters/XRequestId"
      responses:
        "200":
          description: Scheme list returned
          content:
            application/json:
              schema:
                $ref: "#/components/schemas/SchemesResponse"
        "401":
          $ref: "#/components/responses/Unauthorized"
        "500":
          $ref: "#/components/responses/InternalServerError"
      security:
        - ApiKeyAuth: []
security:
  - ApiKeyAuth: []
components:
  parameters:
    XRequestId:
      name: X-Request-ID
      in: header
      required: false
      schema:
        type: string
        format: uuid
      description: Client-supplied correlation ID echoed in response headers for tracing.
  schemas:
    SchemesResponse:
      type: object
      xml:
        name: SchemesResponse
      properties:
        schemes:
          type: array
          items:
            type: object
            properties:
              code:
                $ref: "#/components/schemas/SchemeCode"
              name:
                type: string
              description:
                type: string
              messageTypes:
                type: array
                items:
                  $ref: "#/components/schemas/MessageType"
    SchemeCode:
      type: string
      description: Payment scheme identifier.
      enum:
        - SCT
        - SCT_INST
        - SDD_CORE
        - SDD_B2B
        - OCT_INST
        - CBPRPLUS
        - CHAPS
        - T2
        - EURO1
        - FEDWIRE
        - OTHER
    MessageType:
      type: string
      description: >
        ISO 20022 message type. R-transaction types (pain.002, pain.007,
        pacs.002,

        pacs.004, camt.029, camt.052, camt.053, camt.054, camt.055, camt.056,
        camt.058, camt.110, camt.111) must be submitted to R-transaction
        endpoints only

        (EP-07, EP-15). Submitting them to Check/Convert endpoints returns HTTP
        422 (REG-06).
      enum:
        - pain.001
        - pain.002
        - pain.007
        - pain.008
        - pacs.002
        - pacs.003
        - pacs.004
        - pacs.008
        - pacs.009
        - pacs.010
        - camt.029
        - camt.052
        - camt.053
        - camt.054
        - camt.055
        - camt.056
        - camt.057
        - camt.058
        - camt.060
        - camt.105
        - camt.106
        - camt.107
        - camt.108
        - camt.109
        - camt.110
        - camt.111
    ErrorResponse:
      type: object
      xml:
        name: ErrorResponse
      description: Standard error envelope returned on 4xx and 5xx responses.
      properties:
        code:
          type: integer
          description: HTTP status code.
        message:
          type: string
          description: Human-readable error description.
        requestId:
          type: string
          description: Correlation ID for support.
  responses:
    Unauthorized:
      description: Unauthorized — missing or invalid authentication credentials.
      content:
        application/json:
          schema:
            $ref: "#/components/schemas/ErrorResponse"
          example:
            code: 401
            message: Authentication credentials are missing or invalid.
            requestId: b1a2c3d4-0000-0000-0000-000000000001
        application/xml:
          schema:
            $ref: "#/components/schemas/ErrorResponse"
          example: >
            <?xml version="1.0" encoding="UTF-8"?>

            <ErrorResponse>
              <code>401</code>
              <message>Authentication credentials are missing or invalid.</message>
              <requestId>b1a2c3d4-0000-0000-0000-000000000001</requestId>
            </ErrorResponse>
    InternalServerError:
      description: Internal Server Error — unexpected server-side failure.
      content:
        application/json:
          schema:
            $ref: "#/components/schemas/ErrorResponse"
          example:
            code: 500
            message: An unexpected error occurred. Please contact support with your
              requestId.
            requestId: b1a2c3d4-0000-0000-0000-000000000006
        application/xml:
          schema:
            $ref: "#/components/schemas/ErrorResponse"
          example: |
            <?xml version="1.0" encoding="UTF-8"?>
            <ErrorResponse>
              <code>500</code>
              <message>An unexpected error occurred.</message>
              <requestId>b1a2c3d4-0000-0000-0000-000000000006</requestId>
            </ErrorResponse>
  securitySchemes:
    ApiKeyAuth:
      type: apiKey
      in: header
      name: X-API-Key
      description: Your ioNova platform API key. Generate it from your organisation
        admin in the ioNova app, then paste it here to test.
```