Slash · Authentication Profile

Slash Authentication

Authentication

Slash secures its APIs with apiKey and http across 3 declared security schemes, as derived from its OpenAPI definitions.

CompanyBankingPaymentsFinancial-ServicesFintechCorporate CardsBusiness BankingInvoicingExpense ManagementTreasuryFDX
Methods: apiKey, http Schemes: 3 OAuth flows: API key in: header

Security Schemes

api_key apiKey
· in: header (X-API-Key)
bearer http
scheme: bearer
developer_application http
scheme: basic

Source

Authentication Profile

Raw ↑ 
generated: '2026-07-21'
method: searched
source: openapi/slash-openapi-original.json
docs: https://docs.slash.com/introduction
tenancy_header:
  name: x-legal-entity
  required_for: user-scoped keys (except GET /legal-entity)
oauth_oidc:
  note: >-
    Third-party developer applications additionally use OAuth2/OIDC
    (authorization_code, client_secret_basic) with the permission-key model in
    scopes/slash-scopes.yml. Discovery at api.slash.com/.well-known/openid-configuration.
summary:
  types:
  - apiKey
  - http
  api_key_in:
  - header
schemes:
- name: api_key
  type: apiKey
  in: header
  parameter: X-API-Key
  description: |-
    API key authentication for public API requests.

    Keys come in two flavors:

    - *Legal-entity-scoped keys* are pinned to a single legal entity.
      Minted via the dashboard under a specific entity; every request
      acts on that entity.
    - *User-scoped keys* are pinned to a user and span every legal
      entity that user has access to. Every request made with a
      user-scoped key (except `GET /legal-entity`,
  sources:
  - openapi/slash-openapi-original.json
- name: bearer
  type: http
  scheme: bearer
  sources:
  - openapi/slash-openapi-original.json
- name: developer_application
  type: http
  scheme: basic
  sources:
  - openapi/slash-openapi-original.json

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