Hi @Volkmann Stephan ,
Welcome to Microsoft Q&A forum and thanks for your query.
Unfortunately it is not possible. Currently annotations field in ADF pipeline doesn't support dynamic content, hence you won't be able to differentiate the runs of a particular pipeline for various source systems using annotations.
I would recommend you to please log a feature request in ADF user voice forum: https://feedback.azure.com/forums/270578-azure-data-factory
All the feedback share in this form are actively monitored and reviewed by ADF engineering team. And also do share the link here so that other users with similar idea can upvote and/or comment on your suggestion which would help to increase the priority of feature request.
Here is an existing feedback to support dynamic content for annotations : Allow dynamic content in annotations field Please feel free to upvote/comment on it.
Hope this info helps.
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