# POST /api/promotions/suggest-codes

Suggests promotion codes built from the values the caller has filled in so far.

Memorable codes are guessable by design: they are marketing codes a customer reads off a
flyer. Ask for the private style for a single-use or goodwill discount. Nothing is stored;
a suggestion becomes a promotion only when it is created.

**Operation ID:** `promotionsSuggestCodes`

## Authorization

Requires: Promotions.Promotions, merchant scope.

Requires API key scope: `transactions:write`

Required permissions:
- `Promotions.Promotions`

## Parameters

| Name | In | Required | Type | Description |
| --- | --- | --- | --- | --- |
| suppressNulls | query | no | boolean | If true, omit properties with null values. |

## Request Body

**Content type:** `application/json`

Schema: [`SuggestPromotionCodesInput`](https://devportal.demo.winkpg.io/docs/api/models/SuggestPromotionCodesInput.md)

Properties:
- `merchantId` (string(uuid)): The merchant the promotion will belong to. When given, codes the merchant already uses  are left out of the suggestions. The caller must be authorized over the merchant. Conditional: When MerchantId is not null. (nullable)
- `excludePromotionId` (string(uuid)): The promotion being edited, so its own current code is not treated as taken. (nullable)
- `style` ([PromotionCodeSuggestionStyle](https://devportal.demo.winkpg.io/docs/api/models/PromotionCodeSuggestionStyle.md)): Memorable marketing codes, or private single-use ones.
  Values:
  - `Memorable`: A marketing code a customer can read off a flyer and type at checkout, built from the promotion's own value, name, start date and scope, for example WELCOME10. Guessable by design.
  - `Private`: A code for a single customer or a goodwill discount: a word, a hyphen and four characters drawn from a cryptographic random source, for example THANKS-K7Q2. Nothing in it comes from the promotion's own details, so it cannot be inferred from a flyer or a name. It is still a short bearer value: give the promotion a redemption limit rather than relying on the suffix to keep it private.
- `count` (integer(int32)): How many suggestions to return, between 1 and `MaxCount`. (min 1, max 10)
- `discountType` ([PromotionDiscountType](https://devportal.demo.winkpg.io/docs/api/models/PromotionDiscountType.md)): Whether the value is a percentage or a flat amount. (nullable)
  Values:
  - `Percent`: A percentage of the amount, for example 10 meaning 10%.
  - `Flat`: A flat amount in the promotion's currency, for example 5 meaning 5.00.
- `value` (number(double)): The percentage, or the flat amount. (nullable)
- `currency` (string): The ISO 4217 currency, when the promotion has one. (nullable)
- `name` (string): The operator-facing promotion name. Its first word may appear in a suggestion. (nullable, max length 128)
- `startsAtUtc` (string(date-time)): When the promotion starts. The season and month in a suggestion are read from it. (nullable)
- `appliesToScope` ([PromotionAppliesToScope](https://devportal.demo.winkpg.io/docs/api/models/PromotionAppliesToScope.md)): What the promotion applies to. (nullable)
  Values:
  - `Any`: Anything the merchant charges for. No target list is consulted.
  - `HostedPages`: Only the named hosted payment pages.
  - `Products`: Only the named products.
  - `Plans`: Only the named contract plans.
- `durationMode` ([PromotionDurationMode](https://devportal.demo.winkpg.io/docs/api/models/PromotionDurationMode.md)): How long the discount runs on a recurring charge. (nullable)
  Values:
  - `FirstBillOnly`: Discount only the first bill.
  - `Cycles`: Discount a fixed number of billing cycles.
  - `UntilRemoved`: Discount every bill until someone takes the promotion off the subscription.
- `durationCycles` (integer(int32)): How many billing cycles the discount runs for. (nullable)

**Content type:** `text/json`

Schema: [`SuggestPromotionCodesInput`](https://devportal.demo.winkpg.io/docs/api/models/SuggestPromotionCodesInput.md)

Properties:
- `merchantId` (string(uuid)): The merchant the promotion will belong to. When given, codes the merchant already uses  are left out of the suggestions. The caller must be authorized over the merchant. Conditional: When MerchantId is not null. (nullable)
- `excludePromotionId` (string(uuid)): The promotion being edited, so its own current code is not treated as taken. (nullable)
- `style` ([PromotionCodeSuggestionStyle](https://devportal.demo.winkpg.io/docs/api/models/PromotionCodeSuggestionStyle.md)): Memorable marketing codes, or private single-use ones.
  Values:
  - `Memorable`: A marketing code a customer can read off a flyer and type at checkout, built from the promotion's own value, name, start date and scope, for example WELCOME10. Guessable by design.
  - `Private`: A code for a single customer or a goodwill discount: a word, a hyphen and four characters drawn from a cryptographic random source, for example THANKS-K7Q2. Nothing in it comes from the promotion's own details, so it cannot be inferred from a flyer or a name. It is still a short bearer value: give the promotion a redemption limit rather than relying on the suffix to keep it private.
- `count` (integer(int32)): How many suggestions to return, between 1 and `MaxCount`. (min 1, max 10)
- `discountType` ([PromotionDiscountType](https://devportal.demo.winkpg.io/docs/api/models/PromotionDiscountType.md)): Whether the value is a percentage or a flat amount. (nullable)
  Values:
  - `Percent`: A percentage of the amount, for example 10 meaning 10%.
  - `Flat`: A flat amount in the promotion's currency, for example 5 meaning 5.00.
- `value` (number(double)): The percentage, or the flat amount. (nullable)
- `currency` (string): The ISO 4217 currency, when the promotion has one. (nullable)
- `name` (string): The operator-facing promotion name. Its first word may appear in a suggestion. (nullable, max length 128)
- `startsAtUtc` (string(date-time)): When the promotion starts. The season and month in a suggestion are read from it. (nullable)
- `appliesToScope` ([PromotionAppliesToScope](https://devportal.demo.winkpg.io/docs/api/models/PromotionAppliesToScope.md)): What the promotion applies to. (nullable)
  Values:
  - `Any`: Anything the merchant charges for. No target list is consulted.
  - `HostedPages`: Only the named hosted payment pages.
  - `Products`: Only the named products.
  - `Plans`: Only the named contract plans.
- `durationMode` ([PromotionDurationMode](https://devportal.demo.winkpg.io/docs/api/models/PromotionDurationMode.md)): How long the discount runs on a recurring charge. (nullable)
  Values:
  - `FirstBillOnly`: Discount only the first bill.
  - `Cycles`: Discount a fixed number of billing cycles.
  - `UntilRemoved`: Discount every bill until someone takes the promotion off the subscription.
- `durationCycles` (integer(int32)): How many billing cycles the discount runs for. (nullable)

**Content type:** `application/*+json`

Schema: [`SuggestPromotionCodesInput`](https://devportal.demo.winkpg.io/docs/api/models/SuggestPromotionCodesInput.md)

Properties:
- `merchantId` (string(uuid)): The merchant the promotion will belong to. When given, codes the merchant already uses  are left out of the suggestions. The caller must be authorized over the merchant. Conditional: When MerchantId is not null. (nullable)
- `excludePromotionId` (string(uuid)): The promotion being edited, so its own current code is not treated as taken. (nullable)
- `style` ([PromotionCodeSuggestionStyle](https://devportal.demo.winkpg.io/docs/api/models/PromotionCodeSuggestionStyle.md)): Memorable marketing codes, or private single-use ones.
  Values:
  - `Memorable`: A marketing code a customer can read off a flyer and type at checkout, built from the promotion's own value, name, start date and scope, for example WELCOME10. Guessable by design.
  - `Private`: A code for a single customer or a goodwill discount: a word, a hyphen and four characters drawn from a cryptographic random source, for example THANKS-K7Q2. Nothing in it comes from the promotion's own details, so it cannot be inferred from a flyer or a name. It is still a short bearer value: give the promotion a redemption limit rather than relying on the suffix to keep it private.
- `count` (integer(int32)): How many suggestions to return, between 1 and `MaxCount`. (min 1, max 10)
- `discountType` ([PromotionDiscountType](https://devportal.demo.winkpg.io/docs/api/models/PromotionDiscountType.md)): Whether the value is a percentage or a flat amount. (nullable)
  Values:
  - `Percent`: A percentage of the amount, for example 10 meaning 10%.
  - `Flat`: A flat amount in the promotion's currency, for example 5 meaning 5.00.
- `value` (number(double)): The percentage, or the flat amount. (nullable)
- `currency` (string): The ISO 4217 currency, when the promotion has one. (nullable)
- `name` (string): The operator-facing promotion name. Its first word may appear in a suggestion. (nullable, max length 128)
- `startsAtUtc` (string(date-time)): When the promotion starts. The season and month in a suggestion are read from it. (nullable)
- `appliesToScope` ([PromotionAppliesToScope](https://devportal.demo.winkpg.io/docs/api/models/PromotionAppliesToScope.md)): What the promotion applies to. (nullable)
  Values:
  - `Any`: Anything the merchant charges for. No target list is consulted.
  - `HostedPages`: Only the named hosted payment pages.
  - `Products`: Only the named products.
  - `Plans`: Only the named contract plans.
- `durationMode` ([PromotionDurationMode](https://devportal.demo.winkpg.io/docs/api/models/PromotionDurationMode.md)): How long the discount runs on a recurring charge. (nullable)
  Values:
  - `FirstBillOnly`: Discount only the first bill.
  - `Cycles`: Discount a fixed number of billing cycles.
  - `UntilRemoved`: Discount every bill until someone takes the promotion off the subscription.
- `durationCycles` (integer(int32)): How many billing cycles the discount runs for. (nullable)

## Responses

### 200

OK

**Content type:** `application/json`

Schema: [`ListResultDtoOfPromotionCodeSuggestionDto`](https://devportal.demo.winkpg.io/docs/api/models/ListResultDtoOfPromotionCodeSuggestionDto.md)

Properties:
- `items` (array<[PromotionCodeSuggestionDto](https://devportal.demo.winkpg.io/docs/api/models/PromotionCodeSuggestionDto.md)>): (nullable)
  Fields of each item:
  - `code` (string): The code, in its stored form: trimmed and upper-cased. (nullable)

### 403

Forbidden

**Content type:** `application/json`

Schema: [`RemoteServiceErrorResponse`](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorResponse.md)

Properties:
- `error` ([RemoteServiceErrorInfo](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorInfo.md))

### 401

Unauthorized

**Content type:** `application/json`

Schema: [`RemoteServiceErrorResponse`](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorResponse.md)

Properties:
- `error` ([RemoteServiceErrorInfo](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorInfo.md))

### 400

Bad Request

**Content type:** `application/json`

Schema: [`RemoteServiceErrorResponse`](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorResponse.md)

Properties:
- `error` ([RemoteServiceErrorInfo](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorInfo.md))

_Example: Request failed validation_

One or more fields were rejected before any rule ran. error.code is null on the envelope and the causes are in validationErrors, one entry per failure. An entry carries code when the validator declared a publishable one, and memberPaths when the full path says more than members does (an element inside a collection, for example). Both keys are omitted when they would add nothing.

```json
{
  "error": {
    "code": "null",
    "message": "Your request is not valid!",
    "details": "The following errors were detected during validation.",
    "data": {
      "correlationId": "0123456789abcdef0123456789abcdef"
    },
    "validationErrors": [
      {
        "message": "'Amount' must be greater than 0.",
        "members": [
          "amount"
        ]
      },
      {
        "message": "The card has expired.",
        "members": [
          "expirationDate"
        ],
        "code": "CardData:CardExpired"
      },
      {
        "message": "'Value' must not be empty.",
        "members": [
          "value"
        ],
        "memberPaths": [
          "customFields[2].value"
        ]
      }
    ]
  }
}
```

### 404

Not Found

**Content type:** `application/json`

Schema: [`RemoteServiceErrorResponse`](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorResponse.md)

Properties:
- `error` ([RemoteServiceErrorInfo](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorInfo.md))

_Example: Resource not found_

The id in the path names no record the caller can see. Most resources answer with a null error.code and a message naming the resource type and the id; a resource that publishes a not-found code in the catalog above carries it in error.code instead, so check for one before matching on the message.

```json
{
  "error": {
    "code": "null",
    "message": "There is no entity Transaction with id = 7d1f3a52-0c4e-4b8a-9e21-5a6b7c8d9e00!",
    "details": "null",
    "data": {
      "correlationId": "0123456789abcdef0123456789abcdef"
    },
    "validationErrors": "null"
  }
}
```

### 501

Not Implemented

**Content type:** `application/json`

Schema: [`RemoteServiceErrorResponse`](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorResponse.md)

Properties:
- `error` ([RemoteServiceErrorInfo](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorInfo.md))

### 500

Internal Server Error

**Content type:** `application/json`

Schema: [`RemoteServiceErrorResponse`](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorResponse.md)

Properties:
- `error` ([RemoteServiceErrorInfo](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorInfo.md))

### default

The request failed. The body carries the standard error envelope: a machine-readable `error.code`, a human-readable `error.message`, and `error.validationErrors` when the failure was a validation rejection. The [error reference](https://devportal.demo.winkpg.io/docs/errors.md) lists the values `error.code` can take.

**Content type:** `application/json`

Schema: [`RemoteServiceErrorResponse`](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorResponse.md)

Properties:
- `error` ([RemoteServiceErrorInfo](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorInfo.md))

_Example: Business rule refused the request_

The request was understood and rejected by a platform rule. This is the shape that carries a code from the catalog above, so branch on error.code rather than on the message text. The HTTP status is the one listed against the code.

```json
{
  "error": {
    "code": "Transactions:OperationNotAllowed",
    "message": "The operation 'Void' is not allowed on a Sale transaction with result 'Approved' and settlement state 'Settled'.",
    "details": "null",
    "data": {
      "correlationId": "0123456789abcdef0123456789abcdef"
    },
    "validationErrors": "null"
  }
}
```

### 429

The request was refused because a rate limit was exceeded, or because something a later retry can clear stopped it. A rate limit refusal carries an `application/problem+json` body: wait at least the interval `Retry-After` names before retrying, then back off. Limits are tuned per deployment, so read the allowance from the response headers rather than assuming a fixed ceiling. Any other refusal carries the standard error envelope as `application/json`, and its `error.code` names the cause.

**Content type:** `application/problem+json`

Schema: [`RateLimitProblemDetails`](https://devportal.demo.winkpg.io/docs/api/models/RateLimitProblemDetails.md)

Properties:
- `type` (string) required: The problem type identifier. Always the same value: the failure is the status code itself,  so there is no sub-type for a caller to branch on. (nullable)
- `title` (string) required: A short, human-readable summary of the problem type. (nullable)
- `status` (integer(int32)) required: The HTTP status code, repeated in the body as the problem-details format defines.
- `detail` (string) required: A human-readable explanation of this occurrence of the problem. (nullable)
- `retryAfterSeconds` (integer(int32)) required: How long to wait before retrying, in whole seconds, carrying the same figure as the  `Retry-After` header. Always at least one: a value of zero would invite an immediate  retry that is certain to be rejected again.

**Content type:** `application/json`

Schema: [`RemoteServiceErrorResponse`](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorResponse.md)

Properties:
- `error` ([RemoteServiceErrorInfo](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorInfo.md))

## Example request

Every block below sends the same request. Replace {{BASE_URL}} with the address of the API you are calling and {{API_KEY}} with your own key.

The request body is a SuggestPromotionCodesInput. See the Request body section below for its fields.

### cURL

```bash
curl -X POST "{{BASE_URL}}/api/promotions/suggest-codes" \
  -H "api-key: {{API_KEY}}" \
  -H "Content-Type: application/json" \
  -d '{
  "merchantId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
  "excludePromotionId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
  "style": {},
  "count": 1,
  "discountType": {},
  "value": 0,
  "currency": "",
  "name": "",
  "startsAtUtc": "2026-01-01T00:00:00Z",
  "appliesToScope": {},
  "durationMode": {},
  "durationCycles": 0
}'
```

### PowerShell

```powershell
$headers = @{
    'api-key' = '{{API_KEY}}'
}

$body = @'
{
  "merchantId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
  "excludePromotionId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
  "style": {},
  "count": 1,
  "discountType": {},
  "value": 0,
  "currency": "",
  "name": "",
  "startsAtUtc": "2026-01-01T00:00:00Z",
  "appliesToScope": {},
  "durationMode": {},
  "durationCycles": 0
}
'@

$response = Invoke-RestMethod -Method POST -Uri '{{BASE_URL}}/api/promotions/suggest-codes' `
    -Headers $headers -ContentType 'application/json' -Body $body
```

### TypeScript (SDK)

```bash
npm install @winkpg/winkpg-api
```

```typescript
import { Configuration, PromotionsApi } from '@winkpg/winkpg-api';

const api = new PromotionsApi(new Configuration({
  basePath: '{{BASE_URL}}',
  apiKey: '{{API_KEY}}',
}));

const { data } = await api.promotionsSuggestCodes({
  "merchantId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
  "excludePromotionId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
  "style": {},
  "count": 1,
  "discountType": {},
  "value": 0,
  "currency": "",
  "name": "",
  "startsAtUtc": "2026-01-01T00:00:00Z",
  "appliesToScope": {},
  "durationMode": {},
  "durationCycles": 0
});
```

### TypeScript (raw HTTP)

```typescript
const response = await fetch('{{BASE_URL}}/api/promotions/suggest-codes', {
  method: 'POST',
  headers: {
    "api-key": "{{API_KEY}}",
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "merchantId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
    "excludePromotionId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
    "style": {},
    "count": 1,
    "discountType": {},
    "value": 0,
    "currency": "",
    "name": "",
    "startsAtUtc": "2026-01-01T00:00:00Z",
    "appliesToScope": {},
    "durationMode": {},
    "durationCycles": 0
  }),
});

const data = await response.json();
```

### C# (SDK)

```bash
dotnet add package WinkPg.Api.Client
```

```csharp
using WinkPg.Api.Client.Api;
using WinkPg.Api.Client.Client;
using System.Text.Json;

var config = new Configuration { BasePath = "{{BASE_URL}}" };
config.AddApiKey("api-key", "{{API_KEY}}");

var api = new PromotionsApi(config);
var body = JsonSerializer.Deserialize<SuggestPromotionCodesInput>("""
    {
      "merchantId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
      "excludePromotionId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
      "style": {},
      "count": 1,
      "discountType": {},
      "value": 0,
      "currency": "",
      "name": "",
      "startsAtUtc": "2026-01-01T00:00:00Z",
      "appliesToScope": {},
      "durationMode": {},
      "durationCycles": 0
    }
    """);

var result = await api.PromotionsSuggestCodesAsync(body);
```

### C# (raw HTTP)

```csharp
using System.Text;

using var http = new HttpClient { BaseAddress = new Uri("{{BASE_URL}}") };

var request = new HttpRequestMessage(new HttpMethod("POST"), "/api/promotions/suggest-codes");
request.Headers.Add("api-key", "{{API_KEY}}");

request.Content = new StringContent("""
    {
      "merchantId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
      "excludePromotionId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
      "style": {},
      "count": 1,
      "discountType": {},
      "value": 0,
      "currency": "",
      "name": "",
      "startsAtUtc": "2026-01-01T00:00:00Z",
      "appliesToScope": {},
      "durationMode": {},
      "durationCycles": 0
    }
    """, Encoding.UTF8, "application/json");

var response = await http.SendAsync(request);
response.EnsureSuccessStatusCode();
var json = await response.Content.ReadAsStringAsync();
```

### Python (SDK)

```bash
pip install winkpg-api
```

```python
import winkpg_api

configuration = winkpg_api.Configuration(host="{{BASE_URL}}")
configuration.api_key["ApiKey"] = "{{API_KEY}}"

with winkpg_api.ApiClient(configuration) as client:
    api = winkpg_api.PromotionsApi(client)
    body = winkpg_api.SuggestPromotionCodesInput.from_dict({
      "merchantId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
      "excludePromotionId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
      "style": {},
      "count": 1,
      "discountType": {},
      "value": 0,
      "currency": "",
      "name": "",
      "startsAtUtc": "2026-01-01T00:00:00Z",
      "appliesToScope": {},
      "durationMode": {},
      "durationCycles": 0
    })
    result = api.promotions_suggest_codes(body)
```

### Python (raw HTTP)

```bash
pip install requests
```

```python
import requests

headers = {
    "api-key": "{{API_KEY}}",
    "Content-Type": "application/json",
}

body = {
  "merchantId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
  "excludePromotionId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
  "style": {},
  "count": 1,
  "discountType": {},
  "value": 0,
  "currency": "",
  "name": "",
  "startsAtUtc": "2026-01-01T00:00:00Z",
  "appliesToScope": {},
  "durationMode": {},
  "durationCycles": 0
}

response = requests.request(
    "POST",
    "{{BASE_URL}}/api/promotions/suggest-codes",
    headers=headers,
    json=body,
)
response.raise_for_status()
data = response.json()
```

## See also

- [All documentation](https://devportal.demo.winkpg.io/llms.txt): the machine-readable index of every public page on this site.