Google’s John Mueller Says on Twitter that the URL parameter tool is not a replacement for robot.txt file for blocking content so there is no use of using it. John then was asked, ” How reliable is it?” when setting up “crawl no URLs” of a specific type of URL pattern. John Replied ” It is not a replacement for robots.txt- if you want to be sure that something is not crawled, then you should block it properly.”
Here Are The Tweets :
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It is to note that last year John Mueller said to not make use of robots.txt to block indexing of URLs with parameters. So one must keep in mind this as well.