Customers API Reference | Anytime Capital Docs

Customers are the clients saved on your Customers page. The API lists them, finds one by email, adds them and updates them, with the same rules as the dashboard: one customer per email address, in any letter case. Card buyers are added automatically when they first pay, so look a customer up by email before you create one.

Topic	Detail
Endpoints	`POST /api/v1/customers`, `GET /api/v1/customers`, `GET /api/v1/customers/{id}`, `PATCH /api/v1/customers/{id}`
Key permissions	`customers:write`, `customers:read`
Samples	curl; Node.js 18+ with the built-in `fetch` (in an ES module); the Node SDK (preview: not on npm yet); Python with `requests`.
Every request can also answer	401 `UNAUTHORIZED`, 401 `API_KEY_EXPIRED`, 403 `NOT_ENROLLED`, 403 `PERMISSION_DENIED`, 403 `IP_NOT_ALLOWED`, 429 `RATE_LIMITED`, 500 `INTERNAL_ERROR`. See Error codes.

The customer object

JSON

{
  "object": "customer",
  "livemode": true,
  "id": "cus_1042",
  "name": "Jordan Lee",
  "email": "jordan@example.com",
  "phone": "+1 555 0100",
  "company": "Lee Studio",
  "notes": null,
  "billingAddress": null,
  "taxId": null,
  "country": "US",
  "createdAt": "2026-09-02T11:20:00.000Z"
}

Field	Type	Description
`object`	string	The type of object. Always `customer`.
`livemode`	boolean	False for test-mode data (an `ak_test_` key); true for live data.
`id`	string	`cus_` followed by digits.
`name`	string	Name.
`email`	string or null	Email.
`phone`	string or null	Phone.
`company`	string or null	Company.
`notes`	string or null	Your notes; never shown to the customer.
`billingAddress`	object or null	A postal address printed on invoices and quotes.
`billingAddress.line1`	string	Street address. Up to 200 characters.
`billingAddress.line2`	string or null	Apartment, suite, unit. Up to 200 characters.
`billingAddress.city`	string	City. Up to 100 characters.
`billingAddress.state`	string or null	State, province or region. Up to 100 characters.
`billingAddress.postalCode`	string	Postal code. Up to 20 characters.
`billingAddress.country`	string	ISO 3166-1 alpha-2 country code.
`taxId`	string or null	VAT, EIN or other tax number.
`country`	string or null	ISO 3166-1 alpha-2, from what you saved or their card's billing address.
`createdAt`	string (date-time)	Added.

Endpoints

Create a customer

POST/api/v1/customers

customers:writeSupports Idempotency-Key.

One customer per email: 409 DUPLICATE_CUSTOMER otherwise. Card buyers are also added on their own when they first pay, so look up by email before creating.

Headers

Idempotency-Key string: Recommended. A unique key such as a UUID: a retry with the same key within 24 hours gets the first response back instead of acting twice. See Idempotency.

Body

name stringrequired: The customer's name. Up to 255 characters.
email string (email): One customer per email address. Up to 255 characters.
phone string: Phone. Up to 50 characters.
company string: Company. Up to 255 characters.
notes string: Your notes. Up to 2000 characters.
billingAddress object or null: A postal address printed on invoices and quotes.
billingAddress.line1 stringrequired: Street address. Up to 200 characters.
billingAddress.line2 string or null: Apartment, suite, unit. Up to 200 characters.
billingAddress.city stringrequired: City. Up to 100 characters.
billingAddress.state string or null: State, province or region. Up to 100 characters.
billingAddress.postalCode stringrequired: Postal code. Up to 20 characters.
billingAddress.country stringrequired: ISO 3166-1 alpha-2 country code.
taxId string or null: VAT, EIN or other tax number. Up to 64 characters.

Request

curl -X POST https://anytime-capital.com/api/v1/customers \
  -H "Authorization: Bearer $ANYTIME_API_KEY" \
  -H "Idempotency-Key: customer-jordan" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Jordan Lee",
    "email": "jordan@example.com",
    "company": "Lee Studio"
  }'

const res = await fetch("https://anytime-capital.com/api/v1/customers", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.ANYTIME_API_KEY}`,
    "Content-Type": "application/json",
    "Idempotency-Key": "customer-jordan",
  },
  body: JSON.stringify({
    name: "Jordan Lee",
    email: "jordan@example.com",
    company: "Lee Studio",
  }),
});
const customer = await res.json();
if (!res.ok) throw new Error(`${customer.error.code}: ${customer.error.message}`);

import { AnytimeCapital } from "@anytimecapital/node";

const client = new AnytimeCapital({ apiKey: process.env.ANYTIME_API_KEY! });

const customer = await client.customers.create(
  {
    name: "Jordan Lee",
    email: "jordan@example.com",
    company: "Lee Studio",
  },
  { idempotencyKey: "customer-jordan" },
);

import os

import requests

res = requests.post(
    "https://anytime-capital.com/api/v1/customers",
    headers={
        "Authorization": f"Bearer {os.environ['ANYTIME_API_KEY']}",
        "Idempotency-Key": "customer-jordan",
    },
    json={
        "name": "Jordan Lee",
        "email": "jordan@example.com",
        "company": "Lee Studio",
    },
    timeout=30,
)
customer = res.json()
if not res.ok:
    raise RuntimeError(f"{customer['error']['code']}: {customer['error']['message']}")

Response 201

{
  "object": "customer",
  "livemode": true,
  "id": "cus_1042",
  "name": "Jordan Lee",
  "email": "jordan@example.com",
  "phone": "+1 555 0100",
  "company": "Lee Studio",
  "notes": null,
  "billingAddress": null,
  "taxId": null,
  "country": "US",
  "createdAt": "2026-09-02T11:20:00.000Z"
}

Errors

400INVALID_JSON: The body isn't valid JSON, or couldn't be read. An empty body reads as {}. Send Content-Type: application/json and a JSON object.
400INVALID_INPUT: A field, filter, limit or cursor is missing or invalid. The message starts with the field's name, as in amountCents: …, or reads Invalid cursor. Fix the named field. Don't retry the same request unchanged.
400INVALID_IDEMPOTENCY_KEY: The Idempotency-Key header is empty, longer than 255 characters, or has characters other than printable ASCII. Use a UUID. See Idempotency.
409DUPLICATE_CUSTOMER: Another saved customer already has this email address, in any letter case. Find them with GET /api/v1/customers?email=… and update that customer instead.
422IDEMPOTENCY_KEY_REUSED: The Idempotency-Key was used in the last 24 hours with a different body or endpoint. Use a new key for a new request; reuse a key only to retry the same request.

List customers

GET/api/v1/customers

customers:read

Saved customers, newest first, or one by email.

Query

email string: Only customers with this email, any case. Up to 255 characters.
limit integer: How many objects per page, 1–100. Default 25. See Pagination.
cursor string: The previous page's nextCursor, for the page after it.

Request

curl "https://anytime-capital.com/api/v1/customers?email=jordan%40example.com" \
  -H "Authorization: Bearer $ANYTIME_API_KEY"

const res = await fetch("https://anytime-capital.com/api/v1/customers?email=jordan%40example.com", {
  headers: { Authorization: `Bearer ${process.env.ANYTIME_API_KEY}` },
});
const page = await res.json();
if (!res.ok) throw new Error(`${page.error.code}: ${page.error.message}`);

import { AnytimeCapital } from "@anytimecapital/node";

const client = new AnytimeCapital({ apiKey: process.env.ANYTIME_API_KEY! });

const page = await client.customers.list({ email: "jordan@example.com" });

import os

import requests

res = requests.get(
    "https://anytime-capital.com/api/v1/customers",
    headers={"Authorization": f"Bearer {os.environ['ANYTIME_API_KEY']}"},
    params={"email": "jordan@example.com"},
    timeout=30,
)
page = res.json()
if not res.ok:
    raise RuntimeError(f"{page['error']['code']}: {page['error']['message']}")

Response 200

{
  "object": "list",
  "data": [
    {
      "object": "customer",
      "livemode": true,
      "id": "cus_1042",
      "name": "Jordan Lee",
      "email": "jordan@example.com",
      "phone": "+1 555 0100",
      "company": "Lee Studio",
      "notes": null,
      "billingAddress": null,
      "taxId": null,
      "country": "US",
      "createdAt": "2026-09-02T11:20:00.000Z"
    }
  ],
  "hasMore": false,
  "nextCursor": null
}

Errors

400INVALID_INPUT: A field, filter, limit or cursor is missing or invalid. The message starts with the field's name, as in amountCents: …, or reads Invalid cursor. Fix the named field. Don't retry the same request unchanged.

Get a customer

GET/api/v1/customers/{id}

customers:read

One saved customer. Customers removed in the dashboard answer 404.

Path

id stringrequired: cus_…

Request

curl https://anytime-capital.com/api/v1/customers/cus_1042 \
  -H "Authorization: Bearer $ANYTIME_API_KEY"

const res = await fetch("https://anytime-capital.com/api/v1/customers/cus_1042", {
  headers: { Authorization: `Bearer ${process.env.ANYTIME_API_KEY}` },
});
const customer = await res.json();
if (!res.ok) throw new Error(`${customer.error.code}: ${customer.error.message}`);

import { AnytimeCapital } from "@anytimecapital/node";

const client = new AnytimeCapital({ apiKey: process.env.ANYTIME_API_KEY! });

const customer = await client.customers.retrieve("cus_1042");

import os

import requests

res = requests.get(
    "https://anytime-capital.com/api/v1/customers/cus_1042",
    headers={"Authorization": f"Bearer {os.environ['ANYTIME_API_KEY']}"},
    timeout=30,
)
customer = res.json()
if not res.ok:
    raise RuntimeError(f"{customer['error']['code']}: {customer['error']['message']}")

Response 200

{
  "object": "customer",
  "livemode": true,
  "id": "cus_1042",
  "name": "Jordan Lee",
  "email": "jordan@example.com",
  "phone": "+1 555 0100",
  "company": "Lee Studio",
  "notes": null,
  "billingAddress": null,
  "taxId": null,
  "country": "US",
  "createdAt": "2026-09-02T11:20:00.000Z"
}

Errors

404NOT_FOUND: No such object on your business (an id from another business reads the same), or no such endpoint under /api/v1, which still answers in JSON. Check the id and the path. Ids are case-sensitive.

Update a customer

PATCH/api/v1/customers/{id}

customers:writeSupports Idempotency-Key.

Send only what changes; null clears an optional field.

Path

id stringrequired: cus_…

Headers

Idempotency-Key string: Recommended. A unique key such as a UUID: a retry with the same key within 24 hours gets the first response back instead of acting twice. See Idempotency.

Body

name string: The customer's name. Up to 255 characters.
email string (email) or null: One customer per email address. Up to 255 characters.
phone string or null: Phone. Up to 50 characters.
company string or null: Company. Up to 255 characters.
notes string or null: Your notes. Up to 2000 characters.
billingAddress object or null: A postal address printed on invoices and quotes.
billingAddress.line1 stringrequired: Street address. Up to 200 characters.
billingAddress.line2 string or null: Apartment, suite, unit. Up to 200 characters.
billingAddress.city stringrequired: City. Up to 100 characters.
billingAddress.state string or null: State, province or region. Up to 100 characters.
billingAddress.postalCode stringrequired: Postal code. Up to 20 characters.
billingAddress.country stringrequired: ISO 3166-1 alpha-2 country code.
taxId string or null: VAT, EIN or other tax number. Up to 64 characters.

Request

curl -X PATCH https://anytime-capital.com/api/v1/customers/cus_1042 \
  -H "Authorization: Bearer $ANYTIME_API_KEY" \
  -H "Idempotency-Key: customer-jordan-phone" \
  -H "Content-Type: application/json" \
  -d '{
    "phone": "+1 555 0199",
    "notes": null
  }'

const res = await fetch("https://anytime-capital.com/api/v1/customers/cus_1042", {
  method: "PATCH",
  headers: {
    Authorization: `Bearer ${process.env.ANYTIME_API_KEY}`,
    "Content-Type": "application/json",
    "Idempotency-Key": "customer-jordan-phone",
  },
  body: JSON.stringify({ phone: "+1 555 0199", notes: null }),
});
const customer = await res.json();
if (!res.ok) throw new Error(`${customer.error.code}: ${customer.error.message}`);

import { AnytimeCapital } from "@anytimecapital/node";

const client = new AnytimeCapital({ apiKey: process.env.ANYTIME_API_KEY! });

const customer = await client.customers.update(
  "cus_1042",
  { phone: "+1 555 0199", notes: null },
  { idempotencyKey: "customer-jordan-phone" },
);

import os

import requests

res = requests.patch(
    "https://anytime-capital.com/api/v1/customers/cus_1042",
    headers={
        "Authorization": f"Bearer {os.environ['ANYTIME_API_KEY']}",
        "Idempotency-Key": "customer-jordan-phone",
    },
    json={"phone": "+1 555 0199", "notes": None},
    timeout=30,
)
customer = res.json()
if not res.ok:
    raise RuntimeError(f"{customer['error']['code']}: {customer['error']['message']}")

Response 200

{
  "object": "customer",
  "livemode": true,
  "id": "cus_1042",
  "name": "Jordan Lee",
  "email": "jordan@example.com",
  "phone": "+1 555 0199",
  "company": "Lee Studio",
  "notes": null,
  "billingAddress": null,
  "taxId": null,
  "country": "US",
  "createdAt": "2026-09-02T11:20:00.000Z"
}

Errors

400INVALID_JSON: The body isn't valid JSON, or couldn't be read. An empty body reads as {}. Send Content-Type: application/json and a JSON object.
400INVALID_INPUT: A field, filter, limit or cursor is missing or invalid. The message starts with the field's name, as in amountCents: …, or reads Invalid cursor. Fix the named field. Don't retry the same request unchanged.
400INVALID_IDEMPOTENCY_KEY: The Idempotency-Key header is empty, longer than 255 characters, or has characters other than printable ASCII. Use a UUID. See Idempotency.
404NOT_FOUND: No such object on your business (an id from another business reads the same), or no such endpoint under /api/v1, which still answers in JSON. Check the id and the path. Ids are case-sensitive.
409DUPLICATE_CUSTOMER: Another saved customer already has this email address, in any letter case. Find them with GET /api/v1/customers?email=… and update that customer instead.
422IDEMPOTENCY_KEY_REUSED: The Idempotency-Key was used in the last 24 hours with a different body or endpoint. Use a new key for a new request; reuse a key only to retry the same request.

Find or create

To keep one record per person, look the email up first and create only when nothing comes back. Two processes doing this at once can race: the second create answers 409 DUPLICATE_CUSTOMER, so treat that as “found” and list by email again.

Node.js 18+

const API = "https://anytime-capital.com/api/v1";
const headers = { Authorization: `Bearer ${process.env.ANYTIME_API_KEY}` };

export async function findOrCreateCustomer({ name, email }) {
  const find = async () => {
    const res = await fetch(`${API}/customers?email=${encodeURIComponent(email)}`, { headers });
    const page = await res.json();
    if (!res.ok) throw new Error(`${page.error.code}: ${page.error.message}`);
    return page.data[0] ?? null;
  };
  const existing = await find();
  if (existing) return existing;

  const res = await fetch(`${API}/customers`, {
    method: "POST",
    headers: { ...headers, "Content-Type": "application/json" },
    body: JSON.stringify({ name, email }),
  });
  const customer = await res.json();
  // Someone else created them first, or our earlier attempt went through:
  // one customer per email makes the retry safe without an Idempotency-Key.
  if (res.status === 409 && customer.error.code === "DUPLICATE_CUSTOMER") return find();
  if (!res.ok) throw new Error(`${customer.error.code}: ${customer.error.message}`);
  return customer;
}

customer.created and customer.updated webhooks carry this object whenever a customer is added or changed, by hand, by the API or when they first pay.

Anytime Capital is a fintech company, not a bank. Payment processing, banking and payout services are provided by Anytime Capital's licensed partners. Rates shown are for US card payments; international cards, currency conversion and disputes may carry additional fees shown in your dashboard before you accept a payment.

Topic	Detail
Endpoints	`POST /api/v1/customers`, `GET /api/v1/customers`, `GET /api/v1/customers/{id}`, `PATCH /api/v1/customers/{id}`
Key permissions	`customers:write`, `customers:read`
Samples	curl; Node.js 18+ with the built-in `fetch` (in an ES module); the Node SDK (preview: not on npm yet); Python with `requests`.
Every request can also answer	401 `UNAUTHORIZED`, 401 `API_KEY_EXPIRED`, 403 `NOT_ENROLLED`, 403 `PERMISSION_DENIED`, 403 `IP_NOT_ALLOWED`, 429 `RATE_LIMITED`, 500 `INTERNAL_ERROR`. See Error codes.

The customer object

JSON

{
  "object": "customer",
  "livemode": true,
  "id": "cus_1042",
  "name": "Jordan Lee",
  "email": "jordan@example.com",
  "phone": "+1 555 0100",
  "company": "Lee Studio",
  "notes": null,
  "billingAddress": null,
  "taxId": null,
  "country": "US",
  "createdAt": "2026-09-02T11:20:00.000Z"
}

Field	Type	Description
`object`	string	The type of object. Always `customer`.
`livemode`	boolean	False for test-mode data (an `ak_test_` key); true for live data.
`id`	string	`cus_` followed by digits.
`name`	string	Name.
`email`	string or null	Email.
`phone`	string or null	Phone.
`company`	string or null	Company.
`notes`	string or null	Your notes; never shown to the customer.
`billingAddress`	object or null	A postal address printed on invoices and quotes.
`billingAddress.line1`	string	Street address. Up to 200 characters.
`billingAddress.line2`	string or null	Apartment, suite, unit. Up to 200 characters.
`billingAddress.city`	string	City. Up to 100 characters.
`billingAddress.state`	string or null	State, province or region. Up to 100 characters.
`billingAddress.postalCode`	string	Postal code. Up to 20 characters.
`billingAddress.country`	string	ISO 3166-1 alpha-2 country code.
`taxId`	string or null	VAT, EIN or other tax number.
`country`	string or null	ISO 3166-1 alpha-2, from what you saved or their card's billing address.
`createdAt`	string (date-time)	Added.

Endpoints

Create a customer

POST/api/v1/customers

customers:writeSupports Idempotency-Key.

One customer per email: 409 DUPLICATE_CUSTOMER otherwise. Card buyers are also added on their own when they first pay, so look up by email before creating.

Headers

Idempotency-Key string: Recommended. A unique key such as a UUID: a retry with the same key within 24 hours gets the first response back instead of acting twice. See Idempotency.

Body

name stringrequired: The customer's name. Up to 255 characters.
email string (email): One customer per email address. Up to 255 characters.
phone string: Phone. Up to 50 characters.
company string: Company. Up to 255 characters.
notes string: Your notes. Up to 2000 characters.
billingAddress object or null: A postal address printed on invoices and quotes.
billingAddress.line1 stringrequired: Street address. Up to 200 characters.
billingAddress.line2 string or null: Apartment, suite, unit. Up to 200 characters.
billingAddress.city stringrequired: City. Up to 100 characters.
billingAddress.state string or null: State, province or region. Up to 100 characters.
billingAddress.postalCode stringrequired: Postal code. Up to 20 characters.
billingAddress.country stringrequired: ISO 3166-1 alpha-2 country code.
taxId string or null: VAT, EIN or other tax number. Up to 64 characters.

Request

curl -X POST https://anytime-capital.com/api/v1/customers \
  -H "Authorization: Bearer $ANYTIME_API_KEY" \
  -H "Idempotency-Key: customer-jordan" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Jordan Lee",
    "email": "jordan@example.com",
    "company": "Lee Studio"
  }'

const res = await fetch("https://anytime-capital.com/api/v1/customers", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.ANYTIME_API_KEY}`,
    "Content-Type": "application/json",
    "Idempotency-Key": "customer-jordan",
  },
  body: JSON.stringify({
    name: "Jordan Lee",
    email: "jordan@example.com",
    company: "Lee Studio",
  }),
});
const customer = await res.json();
if (!res.ok) throw new Error(`${customer.error.code}: ${customer.error.message}`);

import { AnytimeCapital } from "@anytimecapital/node";

const client = new AnytimeCapital({ apiKey: process.env.ANYTIME_API_KEY! });

const customer = await client.customers.create(
  {
    name: "Jordan Lee",
    email: "jordan@example.com",
    company: "Lee Studio",
  },
  { idempotencyKey: "customer-jordan" },
);

import os

import requests

res = requests.post(
    "https://anytime-capital.com/api/v1/customers",
    headers={
        "Authorization": f"Bearer {os.environ['ANYTIME_API_KEY']}",
        "Idempotency-Key": "customer-jordan",
    },
    json={
        "name": "Jordan Lee",
        "email": "jordan@example.com",
        "company": "Lee Studio",
    },
    timeout=30,
)
customer = res.json()
if not res.ok:
    raise RuntimeError(f"{customer['error']['code']}: {customer['error']['message']}")

Response 201

{
  "object": "customer",
  "livemode": true,
  "id": "cus_1042",
  "name": "Jordan Lee",
  "email": "jordan@example.com",
  "phone": "+1 555 0100",
  "company": "Lee Studio",
  "notes": null,
  "billingAddress": null,
  "taxId": null,
  "country": "US",
  "createdAt": "2026-09-02T11:20:00.000Z"
}

Errors

400INVALID_JSON: The body isn't valid JSON, or couldn't be read. An empty body reads as {}. Send Content-Type: application/json and a JSON object.
400INVALID_INPUT: A field, filter, limit or cursor is missing or invalid. The message starts with the field's name, as in amountCents: …, or reads Invalid cursor. Fix the named field. Don't retry the same request unchanged.
400INVALID_IDEMPOTENCY_KEY: The Idempotency-Key header is empty, longer than 255 characters, or has characters other than printable ASCII. Use a UUID. See Idempotency.
409DUPLICATE_CUSTOMER: Another saved customer already has this email address, in any letter case. Find them with GET /api/v1/customers?email=… and update that customer instead.
422IDEMPOTENCY_KEY_REUSED: The Idempotency-Key was used in the last 24 hours with a different body or endpoint. Use a new key for a new request; reuse a key only to retry the same request.

List customers

GET/api/v1/customers

customers:read

Saved customers, newest first, or one by email.

Query

email string: Only customers with this email, any case. Up to 255 characters.
limit integer: How many objects per page, 1–100. Default 25. See Pagination.
cursor string: The previous page's nextCursor, for the page after it.

Request

curl "https://anytime-capital.com/api/v1/customers?email=jordan%40example.com" \
  -H "Authorization: Bearer $ANYTIME_API_KEY"

const res = await fetch("https://anytime-capital.com/api/v1/customers?email=jordan%40example.com", {
  headers: { Authorization: `Bearer ${process.env.ANYTIME_API_KEY}` },
});
const page = await res.json();
if (!res.ok) throw new Error(`${page.error.code}: ${page.error.message}`);

import { AnytimeCapital } from "@anytimecapital/node";

const client = new AnytimeCapital({ apiKey: process.env.ANYTIME_API_KEY! });

const page = await client.customers.list({ email: "jordan@example.com" });

import os

import requests

res = requests.get(
    "https://anytime-capital.com/api/v1/customers",
    headers={"Authorization": f"Bearer {os.environ['ANYTIME_API_KEY']}"},
    params={"email": "jordan@example.com"},
    timeout=30,
)
page = res.json()
if not res.ok:
    raise RuntimeError(f"{page['error']['code']}: {page['error']['message']}")

Response 200

{
  "object": "list",
  "data": [
    {
      "object": "customer",
      "livemode": true,
      "id": "cus_1042",
      "name": "Jordan Lee",
      "email": "jordan@example.com",
      "phone": "+1 555 0100",
      "company": "Lee Studio",
      "notes": null,
      "billingAddress": null,
      "taxId": null,
      "country": "US",
      "createdAt": "2026-09-02T11:20:00.000Z"
    }
  ],
  "hasMore": false,
  "nextCursor": null
}

Errors

400INVALID_INPUT: A field, filter, limit or cursor is missing or invalid. The message starts with the field's name, as in amountCents: …, or reads Invalid cursor. Fix the named field. Don't retry the same request unchanged.

Get a customer

GET/api/v1/customers/{id}

customers:read

One saved customer. Customers removed in the dashboard answer 404.

Path

id stringrequired: cus_…

Request

curl https://anytime-capital.com/api/v1/customers/cus_1042 \
  -H "Authorization: Bearer $ANYTIME_API_KEY"

const res = await fetch("https://anytime-capital.com/api/v1/customers/cus_1042", {
  headers: { Authorization: `Bearer ${process.env.ANYTIME_API_KEY}` },
});
const customer = await res.json();
if (!res.ok) throw new Error(`${customer.error.code}: ${customer.error.message}`);

import { AnytimeCapital } from "@anytimecapital/node";

const client = new AnytimeCapital({ apiKey: process.env.ANYTIME_API_KEY! });

const customer = await client.customers.retrieve("cus_1042");

import os

import requests

res = requests.get(
    "https://anytime-capital.com/api/v1/customers/cus_1042",
    headers={"Authorization": f"Bearer {os.environ['ANYTIME_API_KEY']}"},
    timeout=30,
)
customer = res.json()
if not res.ok:
    raise RuntimeError(f"{customer['error']['code']}: {customer['error']['message']}")

Response 200

{
  "object": "customer",
  "livemode": true,
  "id": "cus_1042",
  "name": "Jordan Lee",
  "email": "jordan@example.com",
  "phone": "+1 555 0100",
  "company": "Lee Studio",
  "notes": null,
  "billingAddress": null,
  "taxId": null,
  "country": "US",
  "createdAt": "2026-09-02T11:20:00.000Z"
}

Errors

404NOT_FOUND: No such object on your business (an id from another business reads the same), or no such endpoint under /api/v1, which still answers in JSON. Check the id and the path. Ids are case-sensitive.

Update a customer

PATCH/api/v1/customers/{id}

customers:writeSupports Idempotency-Key.

Send only what changes; null clears an optional field.

Path

id stringrequired: cus_…

Headers

Idempotency-Key string: Recommended. A unique key such as a UUID: a retry with the same key within 24 hours gets the first response back instead of acting twice. See Idempotency.

Body

name string: The customer's name. Up to 255 characters.
email string (email) or null: One customer per email address. Up to 255 characters.
phone string or null: Phone. Up to 50 characters.
company string or null: Company. Up to 255 characters.
notes string or null: Your notes. Up to 2000 characters.
billingAddress object or null: A postal address printed on invoices and quotes.
billingAddress.line1 stringrequired: Street address. Up to 200 characters.
billingAddress.line2 string or null: Apartment, suite, unit. Up to 200 characters.
billingAddress.city stringrequired: City. Up to 100 characters.
billingAddress.state string or null: State, province or region. Up to 100 characters.
billingAddress.postalCode stringrequired: Postal code. Up to 20 characters.
billingAddress.country stringrequired: ISO 3166-1 alpha-2 country code.
taxId string or null: VAT, EIN or other tax number. Up to 64 characters.

Request

curl -X PATCH https://anytime-capital.com/api/v1/customers/cus_1042 \
  -H "Authorization: Bearer $ANYTIME_API_KEY" \
  -H "Idempotency-Key: customer-jordan-phone" \
  -H "Content-Type: application/json" \
  -d '{
    "phone": "+1 555 0199",
    "notes": null
  }'

const res = await fetch("https://anytime-capital.com/api/v1/customers/cus_1042", {
  method: "PATCH",
  headers: {
    Authorization: `Bearer ${process.env.ANYTIME_API_KEY}`,
    "Content-Type": "application/json",
    "Idempotency-Key": "customer-jordan-phone",
  },
  body: JSON.stringify({ phone: "+1 555 0199", notes: null }),
});
const customer = await res.json();
if (!res.ok) throw new Error(`${customer.error.code}: ${customer.error.message}`);

import { AnytimeCapital } from "@anytimecapital/node";

const client = new AnytimeCapital({ apiKey: process.env.ANYTIME_API_KEY! });

const customer = await client.customers.update(
  "cus_1042",
  { phone: "+1 555 0199", notes: null },
  { idempotencyKey: "customer-jordan-phone" },
);

import os

import requests

res = requests.patch(
    "https://anytime-capital.com/api/v1/customers/cus_1042",
    headers={
        "Authorization": f"Bearer {os.environ['ANYTIME_API_KEY']}",
        "Idempotency-Key": "customer-jordan-phone",
    },
    json={"phone": "+1 555 0199", "notes": None},
    timeout=30,
)
customer = res.json()
if not res.ok:
    raise RuntimeError(f"{customer['error']['code']}: {customer['error']['message']}")

Response 200

{
  "object": "customer",
  "livemode": true,
  "id": "cus_1042",
  "name": "Jordan Lee",
  "email": "jordan@example.com",
  "phone": "+1 555 0199",
  "company": "Lee Studio",
  "notes": null,
  "billingAddress": null,
  "taxId": null,
  "country": "US",
  "createdAt": "2026-09-02T11:20:00.000Z"
}

Errors

400INVALID_JSON: The body isn't valid JSON, or couldn't be read. An empty body reads as {}. Send Content-Type: application/json and a JSON object.
400INVALID_INPUT: A field, filter, limit or cursor is missing or invalid. The message starts with the field's name, as in amountCents: …, or reads Invalid cursor. Fix the named field. Don't retry the same request unchanged.
400INVALID_IDEMPOTENCY_KEY: The Idempotency-Key header is empty, longer than 255 characters, or has characters other than printable ASCII. Use a UUID. See Idempotency.
404NOT_FOUND: No such object on your business (an id from another business reads the same), or no such endpoint under /api/v1, which still answers in JSON. Check the id and the path. Ids are case-sensitive.
409DUPLICATE_CUSTOMER: Another saved customer already has this email address, in any letter case. Find them with GET /api/v1/customers?email=… and update that customer instead.
422IDEMPOTENCY_KEY_REUSED: The Idempotency-Key was used in the last 24 hours with a different body or endpoint. Use a new key for a new request; reuse a key only to retry the same request.

Find or create

Node.js 18+

const API = "https://anytime-capital.com/api/v1";
const headers = { Authorization: `Bearer ${process.env.ANYTIME_API_KEY}` };

export async function findOrCreateCustomer({ name, email }) {
  const find = async () => {
    const res = await fetch(`${API}/customers?email=${encodeURIComponent(email)}`, { headers });
    const page = await res.json();
    if (!res.ok) throw new Error(`${page.error.code}: ${page.error.message}`);
    return page.data[0] ?? null;
  };
  const existing = await find();
  if (existing) return existing;

  const res = await fetch(`${API}/customers`, {
    method: "POST",
    headers: { ...headers, "Content-Type": "application/json" },
    body: JSON.stringify({ name, email }),
  });
  const customer = await res.json();
  // Someone else created them first, or our earlier attempt went through:
  // one customer per email makes the retry safe without an Idempotency-Key.
  if (res.status === 409 && customer.error.code === "DUPLICATE_CUSTOMER") return find();
  if (!res.ok) throw new Error(`${customer.error.code}: ${customer.error.message}`);
  return customer;
}

customer.created and customer.updated webhooks carry this object whenever a customer is added or changed, by hand, by the API or when they first pay.