Where is log.file.path in the doc?

Hi, we're using filebeats for a lot of months, I know when we use log input automatically are created some object fields

host
agent
log

Currently, I'm using log.file.path but in specific doesn't appear in the doc.

But I can't find the specification about these fields in the official doc, I'm trying to find them but looks impossible.

I'm searching in the following URL Log file content fields | Filebeat Reference [7.12] | Elastic

Please, guide me