I will check with WMF-Legal to see what policies and processes need to be followed in selecting a content license.

As the WMF-Legal project tag was added to this task, some general information to avoid wrong expectations:
Please note that public tasks in Wikimedia Phabricator are in general not a place where to expect feedback from the Legal Team of the Wikimedia Foundation due to the scope of the team and/or nature of legal topics. See the project tag description.
Please see https://meta.wikimedia.org/wiki/Legal for when and how to contact the Legal Team. Thanks!

@Lydia_Pintscher Do you have any advice you can share?

Creative Commons Attribution-ShareAlike 4.0 International License - The most recent version of the CC-BY license family which is used for main namespace content on most (all?) Wikimedia wikis.

I don't know of any WMF wiki that uses CC BY-SA 4.0. Most use CC BY-SA 3.0, and some use others, such as CC BY 2.5.
CC BY-SA 4.0 is not considered compatible with CC BY-SA 3.0 by WMF Legal.

In T288832#7281739, @Keegan wrote:

@Lydia_Pintscher Do you have any advice you can share?

Happy to chime in, yes. Is there an example of the data we're talking about that I could look at?

In T288832#7281756, @Lydia_Pintscher wrote:

Happy to chime in, yes. Is there an example of the data we're talking about that I could look at?

The most visually complete toolinfo record in the demo system can be seen at https://toolhub-demo.wmcloud.org/tool/wikimedia-toolhub. Currently a toolinfo record is controlled by a single individual from the point of view of Toolhub. This "owner" is the user who either added the URL the record is obtained from or created the record directly via the API/UI. There are roadmap plans to add other community contributed structured fields to the toolinfo records which will also introduce shared authorship of the records themselves. This is the "annotation" set of features mentioned at https://meta.wikimedia.org/wiki/Toolhub/Data_model

The other type of user contributed content that we will have in the initial launch is a list of toolinfo records such as the one available at https://toolhub-demo.wmcloud.org/list/2.

In T288832#7281742, @JJMC89 wrote:

Creative Commons Attribution-ShareAlike 4.0 International License - The most recent version of the CC-BY license family which is used for main namespace content on most (all?) Wikimedia wikis.

I don't know of any WMF wiki that uses CC BY-SA 4.0. Most use CC BY-SA 3.0, and some use others, such as CC BY 2.5.
CC BY-SA 4.0 is not considered compatible with CC BY-SA 3.0 by WMF Legal.

Thank you for this information @JJMC89! I did know that article content was more commonly CC-BY-SA 3.0 and that CC-BY-SA 4.0 was primarly in use on Commons for media, but was not aware of potential incompatibility issues of embedding 4.0 licensed content within a 3.0 licensed wiki. I will add this to the specifics to discuss off ticket with the Foundation Legal team. Toolhub does not yet have any direct wiki integrations, but lua access to the Toolhub data store is something that I have hopes of seeing implemented in the future.

IANAL but I would go with CC-0.

Change 721643 had a related patch set uploaded (by BryanDavis; author: Bryan Davis):

[wikimedia/toolhub@main] ui: Add content license information

https://gerrit.wikimedia.org/r/721643

I agree with @Lydia_Pintscher.

We're recommending CC0 for the tool records.

Change 721643 merged by jenkins-bot:

[wikimedia/toolhub@main] ui: Add content license information

https://gerrit.wikimedia.org/r/721643