---
title: Retrieve a Message Batch
url: https://platform.claude.com/docs/en/api/php/messages/batches/retrieve
---

# Retrieve a Message Batch

`$client->messages->batches->retrieve(string messageBatchID, ?string workspaceID): MessageBatch`

**GET** `/v1/messages/batches/{message_batch_id}`

This endpoint is idempotent and can be used to poll for Message Batch completion. To access the results of a Message Batch, make a request to the `results_url` field in the response.

Learn more about the Message Batches API in our [user guide](https://platform.claude.com/docs/en/build-with-claude/batch-processing?sdk_languages=php)

## Parameters

- `messageBatchID: string` (path parameter)

  ID of the Message Batch.

- `workspaceID?: optional string` (header parameter)

  Optional header to select the Workspace for this request. The value is a Workspace ID (for example, `wrkspc_011CZkZaBF1tNoB5wlCeusgy`).

  Only needed for credentials that can act on more than one Workspace. A credential that belongs to a specific Workspace may omit it; if sent, it must match that Workspace.

## Returns

- `class MessageBatch`

  - `"message_batch" type`

    Object type.

    For Message Batches, this is always `"message_batch"`.

  - `string id`

    Unique object identifier.

    The format and length of IDs may change over time.

  - `?\Datetime archivedAt`

    RFC 3339 datetime string representing the time at which the Message Batch was archived and its results became unavailable.

  - `?\Datetime cancelInitiatedAt`

    RFC 3339 datetime string representing the time at which cancellation was initiated for the Message Batch. Specified only if cancellation was initiated.

  - `\Datetime createdAt`

    RFC 3339 datetime string representing the time at which the Message Batch was created.

  - `?\Datetime endedAt`

    RFC 3339 datetime string representing the time at which processing for the Message Batch ended. Specified only once processing ends.

    Processing ends when every request in a Message Batch has either succeeded, errored, canceled, or expired.

  - `\Datetime expiresAt`

    RFC 3339 datetime string representing the time at which the Message Batch will expire and end processing, which is 24 hours after creation.

  - `ProcessingStatus processingStatus`

    Processing status of the Message Batch.

  - `MessageBatchRequestCounts requestCounts`

    Tallies requests within the Message Batch, categorized by their status.

    Requests start as `processing` and move to one of the other statuses only once processing of the entire batch ends. The sum of all values always matches the total number of requests in the batch.

  - `?string resultsURL`

    URL to a `.jsonl` file containing the results of the Message Batch requests. Specified only once processing ends.

    Results in the file are not guaranteed to be in the same order as requests. Use the `custom_id` field to match results to requests.

## Example

```php
<?php

require_once dirname(__DIR__) . '/vendor/autoload.php';

use Anthropic\Client;

$client = new Client(apiKey: 'my-anthropic-api-key');

$messageBatch = $client->messages->batches->retrieve(
  'message_batch_id', workspaceID: 'wrkspc_011CZkZaBF1tNoB5wlCeusgy'
);

var_dump($messageBatch);
```

### Response (200)

```json
{
  "id": "msgbatch_013Zva2CMHLNnXjNJJKqJ2EF",
  "archived_at": "2024-08-20T18:37:24.100435Z",
  "cancel_initiated_at": "2024-08-20T18:37:24.100435Z",
  "created_at": "2024-08-20T18:37:24.100435Z",
  "ended_at": "2024-08-20T18:37:24.100435Z",
  "expires_at": "2024-08-20T18:37:24.100435Z",
  "processing_status": "in_progress",
  "request_counts": {
    "canceled": 10,
    "errored": 30,
    "expired": 10,
    "processing": 100,
    "succeeded": 50
  },
  "results_url": "https://api.anthropic.com/v1/messages/batches/msgbatch_013Zva2CMHLNnXjNJJKqJ2EF/results",
  "type": "message_batch"
}
```