generated: '2026-06-20'
method: searched
status: mixed
notes: >-
  Shift4 does NOT publish an official Model Context Protocol server for the
  Payment Platform REST API. The docs host does expose a Redocly-hosted
  documentation-assistant MCP endpoint at https://docs.shift4.com/_mcp
  (discovered via /.well-known/oauth-authorization-server), which is auth-gated
  (OAuth 2.0 authorization_code / client_credentials, PKCE S256) and answers
  questions over the documentation — it is a docs-search MCP, not a
  transaction-execution MCP bound to the API operations. tools/list over that
  endpoint returns the docs SPA shell / OAuth challenge for anonymous callers,
  so the live tool schemas require authenticated introspection. The tools[]
  below are a CANDIDATE surface derived one-per-operation from the OpenAPI, to
  seed an execution MCP; each cites its backing operationId (real inputSchema =
  that operation's parameters + requestBody in openapi/shift4-payment-api.yml).
servers:
  - name: shift4-docs-assistant
    kind: documentation-assistant
    transport: http
    url: https://docs.shift4.com/_mcp
    status: published
    auth:
      type: oauth2
      authorization_endpoint: https://docs.shift4.com/_mcp/oauth2/auth
      token_endpoint: https://docs.shift4.com/_mcp/oauth2/token-portal
      registration_endpoint: https://docs.shift4.com/_mcp/register
      scopes_supported: [openid, profile, email, offline_access]
      grant_types: [authorization_code, refresh_token, client_credentials]
      code_challenge_methods: [S256]
    gated: true
tools:
  - name: exchange_access_token
    description: Exchange a Client GUID + Auth Token for a merchant Access Token
    source_operation: openapi/shift4-payment-api.yml#accesstokenexchange
  - name: authorize_transaction
    description: Authorize a card payment (hold funds)
    source_operation: openapi/shift4-payment-api.yml#transactionsauthorization
  - name: capture_transaction
    description: Capture a previously authorized transaction
    source_operation: openapi/shift4-payment-api.yml#transactionscapture
  - name: sale_transaction
    description: Authorize and capture in a single call (sale/purchase)
    source_operation: openapi/shift4-payment-api.yml#transactionssale
  - name: refund_transaction
    description: Refund a settled or captured transaction
    source_operation: openapi/shift4-payment-api.yml#refund
  - name: void_transaction
    description: Void an open (unsettled) transaction by invoice
    source_operation: openapi/shift4-payment-api.yml#void
  - name: get_invoice
    description: Retrieve invoice / transaction status
    source_operation: openapi/shift4-payment-api.yml#getinvoice
  - name: add_token
    description: Tokenize a card into TokenStore (card-on-file)
    source_operation: openapi/shift4-payment-api.yml#tokensadd
  - name: verify_card
    description: Verify a card with the processor
    source_operation: openapi/shift4-payment-api.yml#cardsverify
  - name: create_payment_link
    description: Create a hosted payment link
    source_operation: openapi/shift4-payment-api.yml#paymentslinkcreate
  - name: batch_totals_report
    description: Retrieve batch totals report
    source_operation: openapi/shift4-payment-api.yml#reportsbatchtotals