> ## Documentation Index
> Fetch the complete documentation index at: https://docs.getarca.app/llms.txt
> Use this file to discover all available pages before exploring further.

# Create list

> Creates a new list inside a folder.

<Info>Requires the `lists:write` scope. Viewers cannot create lists.</Info>

## Request body

<ParamField body="workspace_id" type="string" required>
  Numeric ID of the workspace to create the list in.
</ParamField>

<ParamField body="folder_id" type="string">
  Numeric ID of the folder this list belongs to. The folder must exist in the
  same workspace. Unlike the Arca app, this field is required when creating a
  list via the API.
</ParamField>

<ParamField body="name" type="string" required>
  List name.
</ParamField>

<ParamField body="icon" type="string">
  Optional icon identifier slug (e.g., `"folder-1"`, `"chart"`, `"code"`).
</ParamField>

<ParamField body="color" type="string">
  Optional color label. Defaults to `"gray"` if not provided.
</ParamField>

## Response

Returns the created list. The `position` is automatically assigned as one greater than the current maximum position in the workspace.

<ResponseField name="id" type="number" required>
  New list identifier.
</ResponseField>

<ResponseField name="workspace_id" type="number" required>
  Workspace this list belongs to.
</ResponseField>

<ResponseField name="folder_id" type="number|null" required>
  Parent folder ID.
</ResponseField>

<ResponseField name="name" type="string" required>
  List name.
</ResponseField>

<ResponseField name="icon" type="string | null">
  Icon. `null` if not provided.
</ResponseField>

<ResponseField name="color" type="string | null">
  Color. Defaults to `"gray"`.
</ResponseField>

<ResponseField name="position" type="number" required>
  Auto-assigned sort position.
</ResponseField>

<ResponseField name="created_at" type="string" required>
  UTC ISO-8601 creation timestamp.
</ResponseField>

<ResponseExample>
  ```json 201 theme={null}
  {
    "id": 25,
    "workspace_id": 3,
    "folder_id": 10,
    "name": "API Tasks",
    "icon": "folder-1",
    "color": "blue",
    "position": 3,
    "created_at": "2026-03-18T11:00:00.000Z"
  }
  ```

  ```json 400 theme={null}
  {
    "error": "workspace_id is required"
  }
  ```

  ```json 401 theme={null}
  {
    "error": "Invalid API key"
  }
  ```

  ```json 403 theme={null}
  {
    "error": "Scope 'lists:write' is required for this endpoint"
  }
  ```

  ```json 404 theme={null}
  {
    "error": "Folder not found"
  }
  ```
</ResponseExample>