I'd say that you should display <https://wikitech.wikimedia.org/wiki/Wikitech:Labs_Terms_of_use#If_my_tools_collect_Private_Information...> *before* you collect that private information. It's true that email addresses are not listed in that page as private information, but EU-wide email addresses are private information so I'd display the warning nonetheless. Thanks.

2018-02-10 12:26 GMT+01:00 Martin Urbanec <martin.urbanec@wikimedia.cz>:

upon request at Czech Wikipedia's helpdesk I created a tool that sends notifications about new weekly articles by e-mail together with its first paragraph and link to it. To accomplish such a thing I need user's email, so I firstly decided to store it in a database. To prevent this tool from spamming I of course require its confirmation by accessing an URL with a random string (MD5 hash of user's email and random number from 1 to 100; I mean, those two things are in one hash). You can have a look at this tool at tools.wmflabs.org/wiki2email/.

My question is: Is this okay? Should I add some kind of formal information to the tool? If so, is there some help page? Should I stop with collecting mails at all and use some WMF-maintained service for mass-emailing (mailman at lists.wikimedia.org maybe?) and make the tool to just send an email to the list itself? 

This question came to my mind before creating, so I do appologize for asking after programming. 

Best regards, 
Martin Urbanec
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