code: func protoMessageDoc(msg proto.Message) (name, doc string) {
  	withDesc, ok := msg.(descriptor.Message)
  	if !ok {
  		return "", ""
  	}
  
  	fd, md := descriptor.ForMessage(withDesc)
  	if fd == nil || md == nil {
  		return "", ""
  	}
  
  	for _, info := range publicProtos {
  		// Find the exact same *.proto file within publicProtos struct.
  		if info.goPath == fd.GetName() {
  			if info.docURL == "" {
  				return "", "" // no docs for it
  			}
  			return md.GetName(), info.docURL
  		}
  	}
  
  	return "", "" // not a public proto
  }
docs: // protoMessageDoc returns the message name and a link to its schema doc.
  //
  // If there's no documentation, returns two empty strings.