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

# Smartlead: Reply To Lead Thread

> Reply to a lead's email in a Smartlead campaign thread. Includes SDK V2 guidance, input constraints, response fields, and Deepline credit cost.

Reply to a lead's email in a Smartlead campaign thread.

> [!NOTE]
>
> Tool ID: `smartlead_reply_to_lead_thread`

## Run this action

This action has conditional or dynamic inputs. A static example cannot describe these inputs reliably.

Read the live contract before you execute this action:

```bash theme={"languages":{"custom":["/languages/deepline-prompt.json"]}}
deepline describe smartlead_reply_to_lead_thread --json
```

## Example response

The static output schema lacks the details for a reliable example. Use `deepline describe smartlead_reply_to_lead_thread --json` for the complete live contract.

## Input reference

Smartlead reply to lead thread input.

| Name | Type | Required | Default | Details |
| - | - | - | - | - |
| `payload.campaign_id` | `string \| integer` | Yes | — | Smartlead campaign identifier (number or positive numeric string). |
| `payload.email_stats_id` | `string` | Yes | — | Minimum length: 1. |
| `payload.email_body` | `string` | Yes | — | Minimum length: 1. |
| `payload.reply_message_id` | `string` | Yes | — | Minimum length: 1. |
| `payload.reply_email_time` | `string` | Yes | — | ISO datetime (e.g. 2026-01-15T09:30:00.000Z). Minimum length: 1. Pattern: `^\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}`. |
| `payload.reply_email_body` | `string` | No | — | Minimum length: 1. |
| `payload.cc` | `string` | No | — | — |
| `payload.bcc` | `string` | No | — | — |
| `payload.add_signature` | `boolean` | No | — | — |

<details>
  <summary>Show raw input schema</summary>

  ### Input JSON Schema

  ```json theme={"languages":{"custom":["/languages/deepline-prompt.json"]}}
  {
    "type": "object",
    "description": "Smartlead reply to lead thread input.",
    "properties": {
      "campaign_id": {
        "description": "Smartlead campaign identifier (number or positive numeric string).",
        "anyOf": [
          {
            "type": "string",
            "description": "Smartlead campaign identifier (number or positive numeric string).",
            "minLength": 1,
            "pattern": "^\\d+$"
          },
          {
            "type": "integer",
            "description": "Smartlead campaign identifier (number or positive numeric string).",
            "minimum": 1
          }
        ]
      },
      "email_stats_id": {
        "type": "string",
        "minLength": 1
      },
      "email_body": {
        "type": "string",
        "minLength": 1,
        "allowsTemplatePlaceholders": true
      },
      "reply_message_id": {
        "type": "string",
        "minLength": 1
      },
      "reply_email_time": {
        "type": "string",
        "description": "ISO datetime (e.g. 2026-01-15T09:30:00.000Z).",
        "minLength": 1,
        "pattern": "^\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}"
      },
      "reply_email_body": {
        "type": "string",
        "minLength": 1,
        "allowsTemplatePlaceholders": true
      },
      "cc": {
        "type": "string"
      },
      "bcc": {
        "type": "string"
      },
      "add_signature": {
        "type": "boolean"
      }
    },
    "required": [
      "campaign_id",
      "email_stats_id",
      "email_body",
      "reply_message_id",
      "reply_email_time"
    ],
    "additionalProperties": false
  }
  ```
</details>

## Output reference

Raw Smartlead lead reply payload.

The static output schema is not available. Run `deepline describe smartlead_reply_to_lead_thread --json` for the live contract.

<details>
  <summary>Show raw output schema</summary>

  ### Output JSON Schema

  ```json theme={"languages":{"custom":["/languages/deepline-prompt.json"]}}
  {
    "description": "Raw Smartlead lead reply payload."
  }
  ```
</details>

## Deepline cost

* Pricing model: `fixed` (per call).
* Estimated Deepline credits: `0` per pricing unit.
* Provider-native pricing may still exist outside Deepline credit billing.

## Related documentation

* [SDK V2 quickstart](https://deepline.com/docs/sdk-v2/quickstart.md)
* [SDK reference](https://deepline.com/docs/sdk-v2/sdk-reference.md)
* [Run tools across a CSV](https://deepline.com/docs/sdk-v2/batch-csv.md)


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