New installation of AppDaemon not starting with error

I’m getting the following errors in my AppDaemon log file, and it fails to start. Any pointers as to what the problem might be?

2024-01-12 07:40:27.539270 INFO AppDaemon: AppDaemon Version 4.4.2 starting
2024-01-12 07:40:27.540102 INFO AppDaemon: Python version is 3.11.6
2024-01-12 07:40:27.540499 INFO AppDaemon: Configuration read from: /config/appdaemon.yaml
2024-01-12 07:40:27.540882 INFO AppDaemon: Added log: AppDaemon
2024-01-12 07:40:27.541285 INFO AppDaemon: Added log: Error
2024-01-12 07:40:27.541629 INFO AppDaemon: Added log: Access
2024-01-12 07:40:27.541974 INFO AppDaemon: Added log: Diag
2024-01-12 07:40:27.870014 WARNING AppDaemon: ------------------------------------------------------------
2024-01-12 07:40:27.870408 WARNING AppDaemon: Unexpected error during run()
2024-01-12 07:40:27.874323 WARNING AppDaemon: ------------------------------------------------------------
Traceback (most recent call last):
File “/usr/lib/python3.11/site-packages/appdaemon/main.py”, line 131, in run
self.AD = ad.AppDaemon(self.logging, loop, **appdaemon)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File “/usr/lib/python3.11/site-packages/appdaemon/appdaemon.py”, line 250, in init
self.plugins = plugins.Plugins(self, args)
^^^^^^^^^^^^^^^^^^^^^^^^^^^
File “/usr/lib/python3.11/site-packages/appdaemon/plugin_management.py”, line 114, in init
class_name = “{}Plugin”.format(basename.capitalize())
^^^^^^^^^^^^^^^^^^^
AttributeError: ‘NoneType’ object has no attribute ‘capitalize’
2024-01-12 07:40:27.876092 INFO AppDaemon: Previous message repeated 1 times
2024-01-12 07:40:27.876413 INFO AppDaemon: AppDaemon Exited

My appdaemon.yaml is:

---
appdaemon:
  latitude: 50.84555
  longitude: -0.94924
  elevation: 2
  time_zone: Europe/London
  thread_duration_warning_threshold: 120
  plugins:
    HASS:
      type: 
  app_dir: /homeassistant/appdaemon/apps
http:
  url: http://127.0.0.1:5050
admin:
api:
hadashboard:
logs:
  main_log:
    filename: /homeassistant/appdaemon/appdaemon.log
    log_size: 1000000000

Found the problem - I’d missed the type: hass setting for the HASS plugin