generated: '2026-07-18'
method: searched
source: https://docs.cello.so/api-reference/introduction
note: >-
  Cello ships a fully separate sandbox environment across API, MCP, and asset
  hosts. Credentials (accessKeyId / secretAccessKey) are issued per environment
  from the Access Keys section of the dashboard; no published magic test values.
environments:
  - name: sandbox
    api_base_url: https://api.sandbox.cello.so
    mcp_url: https://mcp.sandbox.cello.so/mcp
    assets_url: https://assets.sandbox.cello.so/attribution/latest/cello-attribution.js
  - name: production
    api_base_url: https://api.cello.so
    mcp_url: https://mcp.cello.so/mcp
    assets_url: https://assets.cello.so/attribution/latest/cello-attribution.js
credentials:
  model: per-environment access keys
  fields: [accessKeyId, secretAccessKey]
  issued_from: Access Keys section of the Cello dashboard
  note: >-
    Exchange accessKeyId + secretAccessKey at POST /token for a bearer accessToken.
    Sandbox and production keys are distinct. No public test cards or magic
    identifiers are published (Cello is a referral platform, not a card acquirer).
tooling:
  - Event Feed (portal) - inspect incoming signup/purchase event payloads with per-field validation
  - Integration Status (portal) - change signup/purchase sources directly in sandbox