Message - How can i access sub buckets

How can i access critical_host > buckets > "doc_count"

I can access

provider_name.buckets
like this:

"providers":{
    {{#ctx.results.0.aggregations.provider_name.buckets}}
       "provider_name": "{{key}}",
       "Count": {{doc_count}}
    {{/ctx.results.0.aggregations.provider_name.buckets}}
    }