The official ClickUp MCP server can set custom field values but cannot clear them. Setting a dropdown field to "", null or "none" through update_task fails with "Value must be an option index or uuid", and none of the server's operators covers custom fields. The REST API supports it (DELETE /task/{task_id}/field/{field_id}).

Use case: we track the target release of a task in a dropdown field. When a task leaves a release, the field has to be emptied, which today needs a manual step or an automation.

Please let "Set Custom Fields" / update_task accept null to clear a field, or expose "Remove Custom Field Value" as a tool.