# Order of operations (/order-of-operations)



This walkthrough puts the API calls in the order you actually make them: start
from a template, create an order, attach recipients, then confirm and pay. Each
step links to the full reference, where you can fire the request live with your
own key.

<Callout>
  New here? Skim [Authentication & API keys](/authentication-api-keys) first —
  every call below sends your key in the `X-API-KEY` header.
</Callout>

## 1. Get a template ID [#1-get-a-template-id]

Orders are generated from a **template** you design in the LettrLabs app
(handwritten cards, printed mail, and so on). Open the template in the app; its
numeric **template ID** is the `templateId` you pass when creating an order.
There is no public endpoint that lists templates — the ID comes from the app.

## 2. Create the order [#2-create-the-order]

Create the order with [`POST /v1/order`](/api-reference/orders/v1-order-post). The only required
field is `templateId`; recipients and mailing options can be set now or added in
the next step.

```bash
curl -X POST https://app.lettrlabs.com/api/v1/order \
  -H "X-API-KEY: your_api_key_here" \
  -H "Content-Type: application/json" \
  -d '{ "templateId": 12345 }'
```

Keep the returned **order ID** — every later step uses it.

## 3. Add recipients [#3-add-recipients]

Attach (or replace) the order's recipients with
[`PUT /v1/order/{id}/recipients`](/api-reference/orders/v1-order-id-recipients-put). Review what's currently
attached with [`GET /v1/order/{id}/recipients`](/api-reference/orders/v1-order-id-recipients-get).

```bash
curl -X PUT https://app.lettrlabs.com/api/v1/order/ORDER_ID/recipients \
  -H "X-API-KEY: your_api_key_here" \
  -H "Content-Type: application/json" \
  -d '[ { /* see the reference for the recipient shape */ } ]'
```

## 4. Preview a proof (optional) [#4-preview-a-proof-optional]

Before you pay, pull a rendered proof with
[`GET /v1/order/{id}/proof`](/api-reference/orders/v1-order-id-proof-get) to confirm the mail looks right.

## 5. Check out [#5-check-out]

Confirm and pay for the order with
[`POST /v1/order/{id}/checkout`](/api-reference/orders/v1-order-id-checkout-post). Until you check out, the order
is a draft and nothing mails.

```bash
curl -X POST https://app.lettrlabs.com/api/v1/order/ORDER_ID/checkout \
  -H "X-API-KEY: your_api_key_here"
```

## After it mails [#after-it-mails]

* Track recipient‑level delivery and engagement with **Order Recipient
  Analytics** (see the [API Reference](/api-reference)).
* Record outcomes with conversions — see
  [Attributions & Conversions](/attributions-and-conversions).

<Callout type="warn">
  Re‑sending `POST /v1/order` creates a **new** order every time — there is no
  automatic de‑duplication. See the idempotency note in
  [Creating an Order](/creating-an-order) before adding retries.
</Callout>