Get one Customer

Fetch one Customer by external id. Amounts and currencyCode are the record's own transaction currency. Records created in act may take up to one export cycle to become readable.

Path Parameters

external_id
Type: string
required

The record's external id.

Query Parameters

expand
Type: array of "invoices" or "payments"enumnullable

Linked records to include under expanded (repeat the key).
include_deleted
Type: boolean

Return the record even if act has deleted it; it then carries customFields.t0_deleted_at.
entity
Type: string

External id of the entity to act for, from GET /v1/entities. Required when signed in with OAuth (an organization can hold several entities; ask the user which one if more than one could apply). Optional with an API key, which is scoped to one entity already.

Responses

application/json
400

Signed in with OAuth and no entity given (CAPI12).
401

The credential was refused: none sent (CAPI11), an API key that is not valid (CAPI15), or an OAuth sign-in that has expired (CAPI16), was not issued for this API (CAPI17), names an organization T0 does not hold (CAPI18) or a membership that is no longer usable (CAPI19). detail says what to do.
403

The key lacks customer_api:read, or the signed-in user cannot read this record type on the entity (CAPI71); or entity is not the key's own (CAPI14).
404

No record of this type with that id in the entity (CAPI61), or no such entity in your organization (CAPI13).
409

The id resolves to more than one record of this type (CAPI63), or the entity has no applied books start date (CAPI67).
application/json

get/v1/customers/{external_id}

curl 'https://api.t0.ai/v1/customers/{external_id}?include_deleted=false' \
  --header 'Authorization: Bearer YOUR_SECRET_TOKEN'

Show Schema

{
  "id": {
    "dataType": "Adjustment",
    "externalId": "string",
    "platformDataType": "string",
    "platformId": "string",
    "platformType": "string"
  },
  "data": {
    "customFields": {
      "additionalProperty": "anything"
    },
    "date": "2026-11-11",
    "email": "string",
    "name": "string"
  },
  "links": [
    {
      "dataType": "Adjustment",
      "externalId": "string",
      "platformDataType": "string",
      "platformId": "string",
      "platformType": "string"
    }
  ],
  "expanded": {
    "additionalProperty": [
      {
        "data": {
          "amount": 1,
          "currencyCode": "string",
          "customFields": {
            "additionalProperty": "anything"
          },
          "date": "2026-11-11",
          "description": "string",
          "endDate": "2026-11-11",
          "exchangeRates": [],
          "startDate": "2026-11-11"
        },
        "id": {
          "dataType": "Adjustment",
          "externalId": "string",
          "platformDataType": "string",
          "platformId": "string",
          "platformType": "string"
        },
        "links": []
      }
    ]
  },
  "expanded_truncated": [
    "string"
  ]
}

Successful Response

List payments

List customers