# Set Experiment Tag

Launch stage: GA

`POST /api/2.0/mlflow/experiments/set-experiment-tag`

Sets a tag on an experiment. Experiment tags are metadata that can be updated.

API scopes: mlflow

## Request body

- `experiment_id` (string, optional)
  ID of the experiment under which to log the tag. Must be provided.
- `key` (string, optional)
  Name of the tag. Keys up to 250 bytes in size are supported.
- `value` (string, optional)
  String value of the tag being logged. Values up to 64KB in size are supported.

## Response

```json
{}
```