info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments
Panels in a panel group are laid out in rows consisting of two panels per row. An exception to this rule are single panels on a row: these panels take the full width of their containing row.
| `type` | string | no, defaults to `area-chart` | Specifies the panel type to use, for example `area-chart`, `line-chart` or `anomaly-chart`. Only types listed among [all panel types](panel_types.md) are allowed. |
| `title` | string | yes | Heading for the panel. |
| `y_label` | string | no, but highly encouraged | Y-Axis label for the panel. |
| `y_axis` | string | no | Y-Axis configuration for the panel. |
| `max_value` | number | no | Denominator value used for calculating [percentile based results](panel_types.md#percentile-based-results) |
| `metrics` | array | yes | The metrics which should be displayed in the panel. Any number of metrics can be displayed when `type` is `area-chart` or `line-chart`, whereas only 3 can be displayed when `type` is `anomaly-chart`. |
| `links` | array | no | Add links to display on the chart's [context menu](index.md#chart-context-menu). |
| `id` | string | no | Used for associating dashboard metrics with database records. Must be unique across dashboard configuration files. Required for [alerting](../alerts.md) (support not yet enabled, see [relevant issue](https://gitlab.com/gitlab-org/gitlab/-/issues/27980)). |
| `unit` | string | yes | Defines the unit of the query's return data. |
| `label` | string | no, but highly encouraged | Defines the legend-label for the query. Should be unique within the panel's metrics. Can contain time series labels as interpolated variables. |
| `query` | string/number | yes if `query_range` is not defined | Defines the Prometheus query to be used to populate the chart/panel. If defined, the `query` endpoint of the [Prometheus API](https://prometheus.io/docs/prometheus/latest/querying/api/) is used. |
| `query_range` | string/number | yes if `query` is not defined | Defines the Prometheus query to be used to populate the chart/panel. If defined, the `query_range` endpoint of the [Prometheus API](https://prometheus.io/docs/prometheus/latest/querying/api/) is used. |
| `step` | number | no, value is calculated if not defined | Defines query resolution step width in float number of seconds. Metrics on the same panel should use the same `step` value. |
## Dynamic labels
Dynamic labels are useful when multiple time series are returned from a Prometheus query.
When a static label is used and a query returns multiple time series, then all the legend items are labeled the same, which makes identifying each time series difficult:
For labels to be more explicit, using variables that reflect time series labels is a good practice. The variables are replaced by the values of the time series labels when the legend is rendered:
This works by converting the value of `label` to lower-case and, if there are more words separated by spaces, replacing those spaces with an underscore (`_`). The transformed value is then checked against the labels of the time series returned by the Prometheus query. If a time series label is found that is equal to the transformed value, then the label value renders in the legend like this:
This is displayed when the YAML file is larger than 1 MB.
1.`YAML syntax: Invalid configuration format`
This is displayed when the YAML file is empty or does not contain valid YAML.
Metrics Dashboard YAML definition validation information is also available as a [GraphQL API field](../../../api/graphql/reference/index.md#metricsdashboard)
