> ## Documentation Index
> Fetch the complete documentation index at: https://docs.leadlex.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Create Campaign Step

> Append a new email step to a campaign sequence

## Request

### Path Parameters

<ParamField path="id" type="string" required>
  The campaign's unique ID (UUID)
</ParamField>

### Headers

```
Authorization: Bearer wbk_your_api_key_here
Content-Type: application/json
```

<Note>
  Requires an API key with the `campaigns:write` permission. New steps are appended to the end of the sequence. Fires the `campaign.step_created` webhook event.
</Note>

### Body Parameters

<ParamField body="subject" type="string" required>
  Email subject line. Supports merge variables: `{{first_name}}`, `{{last_name}}`, `{{company_name}}`, `{{job_title}}`.
</ParamField>

<ParamField body="body" type="string" required>
  Email body. Plain text or HTML.
</ParamField>

<ParamField body="delay_days" type="integer" default="0">
  Days to wait after the previous step before sending this one.
</ParamField>

<ParamField body="delay_hours" type="integer" default="0">
  Additional hours on top of `delay_days` (0–23).
</ParamField>

<ParamField body="send_condition" type="string" default="always">
  When to send: `always`, `if_no_reply`, `if_no_open`, `if_opened`, `if_clicked`.
</ParamField>

## Response

<ResponseField name="data" type="object">
  <Expandable title="properties">
    <ResponseField name="step" type="object">
      Full step object (same shape as `GET /v1/campaigns/{id}/steps`).
    </ResponseField>
  </Expandable>
</ResponseField>

<CodeGroup>
  ```bash cURL theme={null}
  curl -X POST https://data.leadlex.com/functions/v1/api-gateway/v1/campaigns/cmp_abc123/steps \
    -H "Authorization: Bearer wbk_your_api_key_here" \
    -H "Content-Type: application/json" \
    -d '{
      "subject": "Re: {{company_name}}",
      "body": "Just circling back on my note from last week...",
      "delay_days": 3,
      "send_condition": "if_no_reply"
    }'
  ```

  ```python Python theme={null}
  import requests

  API_KEY = "wbk_your_api_key_here"
  BASE_URL = "https://data.leadlex.com/functions/v1/api-gateway"
  CAMPAIGN_ID = "cmp_abc123"

  response = requests.post(
      f"{BASE_URL}/v1/campaigns/{CAMPAIGN_ID}/steps",
      headers={
          "Authorization": f"Bearer {API_KEY}",
          "Content-Type": "application/json",
      },
      json={
          "subject": "Re: {{company_name}}",
          "body": "Just circling back on my note from last week...",
          "delay_days": 3,
          "send_condition": "if_no_reply",
      },
  )
  ```

  ```javascript JavaScript theme={null}
  const CAMPAIGN_ID = 'cmp_abc123';

  await fetch(
    `https://data.leadlex.com/functions/v1/api-gateway/v1/campaigns/${CAMPAIGN_ID}/steps`,
    {
      method: 'POST',
      headers: {
        'Authorization': 'Bearer wbk_your_api_key_here',
        'Content-Type': 'application/json',
      },
      body: JSON.stringify({
        subject: 'Re: {{company_name}}',
        body: 'Just circling back on my note from last week...',
        delay_days: 3,
        send_condition: 'if_no_reply',
      }),
    }
  );
  ```
</CodeGroup>

### Example Response

```json theme={null}
{
  "data": {
    "step": {
      "id": "step_2",
      "index": 1,
      "subject": "Re: {{company_name}}",
      "body": "Just circling back on my note from last week...",
      "delay_days": 3,
      "delay_hours": 0,
      "send_condition": "if_no_reply",
      "created_at": "2026-04-17T14:30:00Z"
    }
  }
}
```

## Errors

| Status | Code                       | Description                                |
| ------ | -------------------------- | ------------------------------------------ |
| 400    | `missing_required_field`   | `subject` or `body` missing                |
| 400    | `invalid_send_condition`   | `send_condition` is not a recognized value |
| 401    | `invalid_key`              | Invalid or expired API key                 |
| 403    | `insufficient_permissions` | Missing `campaigns:write` permission       |
| 404    | `campaign_not_found`       | No campaign with this ID                   |
| 429    | `rate_limited`             | Rate limit exceeded                        |