# List levels for a grid feed

Returns all levels for the specified grid feed. Levels represent the time-varying signal values that influence smart charging decisions. Each level applies to a specific time interval and has a value between 1 and 100, where values above 50 discourage charging and values below 50 encourage it.
Use `started_at__gte` and `started_at__lte` to filter by time range.

Endpoint: GET /grid_feeds/{grid_feed_id}/levels
Version: 2.0
Security: oauth2

## Path parameters:

  - `grid_feed_id` (string, required)
    Uniquely identify a specific grid feed.

## Query parameters:

  - `started_at__gte` (string)
    Filter for levels starting at or after this datetime (ISO 8601).

  - `started_at__lte` (string)
    Filter for levels starting at or before this datetime (ISO 8601).

  - `page` (number)
    The page number to return results for.

  - `page_size` (integer)
    Specify the number of results to return per page.

## Header parameters:

  - `EvEnergy-Version` (number)
    Specify the version of this endpoint to use.

## Response 200 fields (application/json):

  - `value` (integer, required)
    The grid level value (1-100). 50 is neutral, higher values discourage charging, lower values encourage it.
    Example: 80

  - `started_at` (string, required)
    When this grid level interval began (ISO 8601 datetime). Null if the interval has no lower bound.
    Example: 2024-01-15T18:00:00Z

  - `interval_seconds` (integer, required)
    The duration of this grid level interval in seconds. Null if the interval has no upper or lower bound.
    Example: 10800

  - `created_at` (string, required)
    When this grid level was created (ISO 8601 datetime).
    Example: 2024-01-14T09:00:00Z

## Response 400 fields (application/problem+json):

  - `type` (string)
    Example: https://api.ev.energy/v2/problems/example-problem/

  - `status` (number)
    Example: 400

  - `title` (string, required)
    Example: Short description

  - `detail` (string, required)
    Example: Long, more specific description.

  - `instance` (string)
    Example: https://api.ev.energy/v2/users/user01HN2P75GBNFRJPCZJXEFVXH5E

  - `notification` (object)
    Something that the user should be informed about.

  - `notification.id` (string, required)
    Unique identifier for the Notification
    Example: notf67O36PLTFDB57M0E5L33JZLGM0

  - `notification.url` (string, required)
    Example: https://api.ev.energy/notifications/notf67O36PLTFDB57M0E5L33JZLGM0

  - `notification.message_id` (string, required)
    Internal identifier for this notification type. E.g. 'ERR0023'

  - `notification.category` (string, required)
    Category of this notification type
    Enum: "ACTIONABLE", "SERVICE", "RETRY", "MARKETING", "INTERNAL"

  - `notification.event_time` (string, required)
    The timestamp of the event described by this notification

  - `notification.short_text_title` (string, required)
    Short title for the notification

  - `notification.short_text_body` (string, required)
    Short description of the event being notified

  - `notification.detail_page_title` (string, required)
    Title of a help page giving more information about this notification

  - `notification.detail_page_body` (string, required)
    Text of a help page giving more information about this notification

  - `notification.external_link` (string | null, required)
    URL of a web page giving further information about this notification

  - `notification.external_button_label` (string, required)
    Text to be displayed on a button leading to the external_link location

  - `notification.read_at` (string)
    When the user examined the contents of this notification

  - `notification.resolved_at` (string)
    When the problem associated with this notification was resolved

## Response 401 fields (application/problem+json):

  - `status` (number)
    Example: 401

  - `title` (string, required)
    Example: Unauthorized

  - `detail` (string, required)
    Example: Authentication credentials were not provided.

## Response 403 fields (application/problem+json):

  - `status` (number)
    Example: 403

  - `title` (string, required)
    Example: Forbidden

  - `detail` (string, required)
    Example: You do not have permission to perform this action.

## Response 404 fields (application/problem+json):

  - `status` (number)
    Example: 404

  - `title` (string, required)
    Example: Not found

  - `detail` (string, required)
    Example: Resource does not exist or cannot be accessed.

## Response 406 fields (application/problem+json):

  - `status` (number)
    Example: 406

  - `title` (string, required)
    Example: Not Acceptable

  - `detail` (string, required)
    Example: Could not satisfy the request Accept header.

## Response 429 fields (application/problem+json):

  - `type` (string)
    Example: https://api.ev.energy/v2/problems/example-problem/

  - `status` (number)
    Example: 400

  - `title` (string, required)
    Example: Short description

  - `detail` (string, required)
    Example: Long, more specific description.

  - `instance` (string)
    Example: https://api.ev.energy/v2/users/user01HN2P75GBNFRJPCZJXEFVXH5E

  - `notification` (object)
    Something that the user should be informed about.

  - `notification.id` (string, required)
    Unique identifier for the Notification
    Example: notf67O36PLTFDB57M0E5L33JZLGM0

  - `notification.url` (string, required)
    Example: https://api.ev.energy/notifications/notf67O36PLTFDB57M0E5L33JZLGM0

  - `notification.message_id` (string, required)
    Internal identifier for this notification type. E.g. 'ERR0023'

  - `notification.category` (string, required)
    Category of this notification type
    Enum: "ACTIONABLE", "SERVICE", "RETRY", "MARKETING", "INTERNAL"

  - `notification.event_time` (string, required)
    The timestamp of the event described by this notification

  - `notification.short_text_title` (string, required)
    Short title for the notification

  - `notification.short_text_body` (string, required)
    Short description of the event being notified

  - `notification.detail_page_title` (string, required)
    Title of a help page giving more information about this notification

  - `notification.detail_page_body` (string, required)
    Text of a help page giving more information about this notification

  - `notification.external_link` (string | null, required)
    URL of a web page giving further information about this notification

  - `notification.external_button_label` (string, required)
    Text to be displayed on a button leading to the external_link location

  - `notification.read_at` (string)
    When the user examined the contents of this notification

  - `notification.resolved_at` (string)
    When the problem associated with this notification was resolved