# Contents of a run cache
<a name="workflow-cache-contents"></a>

HealthOmics organizes your run cache with the following structure in your S3 bucket:

```
s3://{cache.S3location}/{cache.uuid}/runID/taskID/{cacheentry.uuid}/
```

The cache.uuid is the globally unique id for the cache. The cacheentry.uuid is the globally unique uuid for a cached task. HealthOmics assigns the uuids to caches and tasks. 

For all workflow engines, the cache contains the following files: 
+ The **\$1cacheentryuuid\$1.json** file – HealthOmics creates this manifest file, which contains information about the cache, including a list of all items in the cache, and the [cache version](how-run-cache.md#workflow-cache-data-versions).
+ Task output files – Each task output consists of one or more files, as defined by the task. 

For a workflow that uses Nextflow, the Nextflow engine creates these additional files in the cache:
+ The **command.out** file – This file contains the task execution stdout contents.
+ The **.exitcode** file – This file contains the task exit code (an integer).

**Note**  
If you want to access intermediate task files in your run cache for advanced troubleshooting, declare these files as task outputs in the workflow definition.