Always getting invalid response error for hash with Rails and jbuilder

I am setting up the middleware like this in my config/application.rb;

if Rails.env.development? || Rails.env.test?
  config.middleware.use Committee::Middleware::RequestValidation, 
	schema_path: 'docs/schema-bundled.yml',
	params_key: 'action_dispatch.request.request_parameters'
  config.middleware.use Committee::Middleware::ResponseValidation, 
	schema_path: 'docs/schema-bundled.yml',
	raise: true
end

Now whenever I render anything from my controllers, like;

def doorkeeper_forbidden_render_options(*)
  { json: { error: { code: 'forbidden', message: 'This action is outside the authorized scopes' } } }
end

I always receive a Committee:InvalidResponse error;

Committee::InvalidResponse: #/components/responses/forbidden/content/application~1json/schema expected , but received Hash: {"error"=>{"code"=>"forbidden", "message"=>"This action is outside the authorized scopes"}}

Where the schema definitions looks like this;

openapi: 3.0.0

paths:
  '/api/v1/accounts/{account_id}':
    get:
      operationId: get_account
      summary: Retrieve an existing acocunt
      description: >
        To show information about an account, send a GET request to
        `/api/v1/accounts/$ACCOUNT_ID`.
      tags:
        - Accounts
      parameters:
        - $ref: '#/components/parameters/account_id'
      responses:
        '401':
          $ref: '#/components/responses/unauthorized'

components:
  parameters:
    account_id:
      in: path
      name: account_id
      description: A unique identifier for an account.
      required: true
      schema:
        type: string
        format: uuid
      example: acf19357-d974-4843-9525-e98426ad5346
  
  schemas:
    error:
      type: object
      properties:
        code:
          type: string
          description: >
            A short identifier corresponding to the HTTP status code returned.
            For example, the identifier for a response returning a 404 status code
            would be "not_found."
          example: not_found
        message:
          type: string
          description: >
            A message providing additional information about the error,
            including details to help resolve it when possible.
          example: The resource you were accessing could not be found.
        request_id:
          type: string
          format: uuid
          description: |
            Optionally, some endpoints may include a request ID that should be
            provided when reporting bugs or opening support tickets to help
            identify the issue.
          example: 4d9d8375-3c56-4925-a3e7-eb137fed17e9
      required:
        - code
        - message

  responses:
    forbidden:
      description: Forbidden.
      content:
        application/json:
          schema:
            type: object
            properties:
              error:
                $ref: '#/components/schemas/error'
          example:
            error:
              code: forbidden
              message: Forbidden to authenticate you.

Am I missing maybe some configuration value?

Start with the middleware configuration in config/application.rb and the supplied OpenAPI schema, then trace Committee::Middleware::ResponseValidation for the rendered controller response. Reproduce the doorkeeper_forbidden_render_options case and compare the response body with the schema; done means the documented Rails and Jbuilder response validates without Committee::InvalidResponse.