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# Custom Language Model Builds Failed

Analyze how often your app-triggered rebuild of a custom language model failed.

## Overview

The data in this report details the number of times that the app-triggered rebuild of a Speech framework custom language model failed.

- Territories: Worldwide
- Platforms: iOS, iPadOS.  For more information about iOS and iPadOS, see the Platforms section in [Data Completeness and Corrections](/documentation/Analytics-Reports/data-completeness-corrections).
- Availability:
  - Daily: Every day.
- History: On request, data is available beginning with iOS 17.4 and iPadOS 17.4.
- Completeness: Data from devices that contribute to this report can arrive as late as 8 days after the date it generates on device. You can download recent data daily, but it might be incomplete, and data updates incrementally daily, until all late-arriving events are available.
- Privacy:
  - Includes data from users who have opted to share their data with Apple and developers.
  - Individual rows will only appear if they have a value of 5 or more.
- Data Context: You can analyze your data with additional context by comparing it with the data in the [App Sessions Context](/documentation/Analytics-Reports/app-sessions-context) report, which provides a count of unique devices that use your app on a specific day. For example, if your app performed an action detailed in this report on 10 unique devices on a specific day, and the App Sessions Context report shows there were 100 unique devices running your app that day, then you can approximate that 10% of the devices running your app performed that action.

## Report Fields

|Report Field       |Description                                                           |Data Type|
|-------------------|----------------------------------------------------------------------|---------|
|Count              |Number of times the event occurred                                    |`integer`|
|Territory          |Country or region in which the event occurred                         |`string` |
|Date               |Date when the event occurred                                          |`string` |
|Platform           |OS version on the device on which the event occurred                  |`string` |
|Device             |Type of device on which the event occurred                            |`string` |
|Build              |Build of device on which event occurred                               |`string` |
|Unique Devices     |The count of unique devices                                           |`integer`|
|Release Type       |Type of software release                                              |`string` |
|Artifact Identifier|A developer-defined string that uniquely identifies the language model|`string` |

## Glossary

|Dimension          |Value |Definition                                                            |
|-------------------|------|----------------------------------------------------------------------|
|Artifact Identifier|string|A developer-defined string that uniquely identifies the language model|

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