Adding piper to a blueprint

I am trying to get a blueprint to use piper to announce over my google homes but am running into an issue. I’ve added this to the blueprint

- alias: Send notification to Google Home devices
  service: tts.speak
    cache: true
    media_player_entity_id: media_player.office_speaker
    message: '{{ agent.response.speech.plain.speech }}'
    entity_id: tts.piper
    language: 'en'

But get the error Message malformed: extra keys not allowed @ data[‘action’][4][‘target’][‘language’]
I can use it just fine if I use piper directly in an automation but I can’t seem to get it working with a blueprint.

Piper doesn’t work like that. It is not a tts…

did you ever figure it out? I am trying the almost the same with the same error. Trying to take the output of opeanAI and speak it to a media player.

That shows how to run any of the 11 TTS core integrations and piper.
You can even just use the blueprint as is, it creates a script you can call to TTS. you can build it with inputs, ot use data statements to add all or some of the data live into the script.