|**CLEARML_LOG_ENVIRONMENT** | List of Environment variable names. These environment variables will be logged in the ClearML task’s configuration hyperparameters `Environment` section. When executed by a ClearML agent, these values will be set in the task’s execution environment. |
|**CLEARML_TASK_NO_REUSE** | Boolean. <br/> When set to `true`, a new task is created for every execution (see Task [reuse](../clearml_sdk/task_sdk#task_reuse). |
|**CLEARML_CACHE_DIR** | Set the path for the ClearML cache directory, where ClearML stores all downloaded content. |
|**CLEARML_DOCKER_IMAGE** | Sets the default docker image to use when running an agent in [Docker mode](../clearml_agent.md#docker-mode). |
|**CLEARML_SUPPRESS_UPDATE_MESSAGE** | Boolean. <br/> When set to `1`, suppresses new ClearML package version availability message. |
|**CLEARML_DEFAULT_OUTPUT_URI** | The default output destination for model checkpoints (snapshots) and artifacts. |
|**CLEARML_SET_ITERATION_OFFSET** | Set initial iteration value for the executed task. The task will report its iterations starting with the specified value +1. Specify `0` to force resetting the iteration count.|