How to Mark a Pull Request Edited

[Susheel Prasad Kanakamedala]

We have 2 plugin hooks which get triggered during the pull request merging (Plugin A --> POST merge, Plugin B --> PRE merge). 

Plugin A creates few more pull requests to down merge the code to other branches.

Plugin B makes some validation on the pull requests.

So, I don't want any validation done (by plugin B) on the pull requests created by plugin A.

Is there any way to identify the pull requests created by Plugin A?

Using Bitbucket server 4.14.5