Hello, Rowemu,

I understand that adding this tag was inspired after the following thread on the forum.
https://community.openstreetmap.org/t/how-to-tag-free-admission-fur-icom-member/131475

The "Any tags you like" policy also mandates that people should make the extra effort to create a proper documentation about new tags they are introducing.

I see on Taginfo that you are currently the sole user of this tag.
https://taginfo.openstreetmap.org/keys/fee:icom_member#overview

Could I invite you to write a description for this tag on the OSM Wiki.  One important aspect here is that the list of museums for which the ICOM membership cards grants free access, should be publicly available, so that other mappers can also add or remove places in the future.  I tried to inspect https://icom.museum/en/network/membership-card/ but the list of eligible museums does not seem easy to find.

Would you please do this?