# Save and Access Metadata Information About Your Processing Job
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To save metadata from the processing container after exiting it, containers can write UTF-8 encoded text to the `/opt/ml/output/message` file. After the processing job enters any terminal status ("`Completed`", "`Stopped`", or "`Failed`"), the "`ExitMessage`" field in [https://docs.amazonaws.cn/sagemaker/latest/APIReference/API_DescribeProcessingJob.html](https://docs.amazonaws.cn/sagemaker/latest/APIReference/API_DescribeProcessingJob.html) contains the first 1 KB of this file. Access that initial part of file with a call to [https://docs.amazonaws.cn/sagemaker/latest/APIReference/API_DescribeProcessingJob.html](https://docs.amazonaws.cn/sagemaker/latest/APIReference/API_DescribeProcessingJob.html), which returns it through the `ExitMessage` parameter. For failed processing jobs, you can use this field to communicate information about why the processing container failed.

**Important**  
Don't write sensitive data to the `/opt/ml/output/message` file. 

If the data in this file isn't UTF-8 encoded, the job fails and returns a `ClientError`. If multiple containers exit with an `ExitMessage,` the content of the `ExitMessage` from each processing container is concatenated, then truncated to 1 KB.