FAMEPedia:Edit filter

The edit filter is a tool that allows editors in the edit filter manager group to set controls mainly to address common patterns of harmful editing. The current filters can be found at Special:AbuseFilter. A filter automatically compares every edit made to FAMEPedia against a defined set of conditions. If an edit matches the conditions of a filter, that filter will respond by logging the edit. It may also tag the edit summary, warn the editor, revoke their autoconfirmed status, and/or disallow the edit entirely.

The term "edit filter" rather than "abuse filter" is currently used for user-facing elements of the filter as some of the edits it flags are not harmful; the terms are otherwise synonymous.

Because even the smallest mistake in editing a filter can significantly disrupt the encyclopedia, only editors who have the required good judgment and technical proficiency are permitted to configure filters. This page does not discuss technical issues concerning the feature; technical information relating to the operation of the edit filter can be found at Extension:AbuseFilter.

Basics of usage
Edit filters are mainly used to identify and mitigate harmful edits by comparing edits with filtering criteria that address patterns of harmful editing. Filters are created and configured by edit filter managers, but they can be requested by any editor.

When an edit that is being saved "triggers" an active filter, the effect depends on a setting associated with that particular filter:
 * The strongest setting is disallow. In this case, the edit is rejected, and the user will see a customisable message (this one by default). A link is provided for reporting false positives. It is also possible to have a user's autoconfirmed status revoked if a user trips the filter.
 * The next lowest setting is to warn. In this case, the user will see a customisable message (this one by default) that the edit may be problematic. The user then has the option to either proceed with the save or abandon the edit.
 * The next lowest setting is to add a tag. In this case, the edit is tagged for review by patrollers.
 * The lowest setting is to log the edit. In this case, the edit is merely added to the AbuseLog. When testing new filters, this is the suggested setting to use.

Recommended uses
Except in urgent situations, new edit filters should generally be tested without any actions specified (simply enabled) until a good number of edits have been logged and checked before being implemented in "warn" or "disallow" modes. If the filter is receiving more than a very small percentage of false positives it should usually not be placed in 'disallow' mode. If a filter is designed to catch good faith edits it should not be placed in disallow mode without an appropriate consensus.

Administrators should be familiar with alternatives that might be more appropriate in a given situation. For example, problems on a single page might be better served with page protection, and problems with page titles or link spam may find the title blacklist and spam blacklist more effective respectively. Because edit filters check every edit in some way, filters that are tripped only rarely are discouraged.

Edit filters should only be set to disallow to prevent edits that substantially all good-faith editors would agree are undesirable, or where a clear consensus has been reached that a specific type of edit should not be allowed. Any doubts regarding setting a filter to disallow should be discussed with other edit filter managers.

Except in urgent situations, new edit filters must not be set to disallow without thorough testing and a notice at the noticeboard to give other edit filter managers and the community time to review the filter for technical accuracy and necessity. In urgent situations, the notice may be made after-the-fact. Prior to and during the review of an edit filter which is set to "disallow" due to an emergency, the editor placing the edit filter is responsible for seeing that the logs are regularly monitored and false positives are minimized. Editors should avoid altering filters in modes other than log-only without some form of testing.

Requesting edit filters
Edit filters can be requested at the Administrators'noticeboard. Administrators monitor this page and implement edit filters when a good case is made. If there is a disagreement, try to build a consensus. The desirability of an edit filter may also emerge from discussions elsewhere on FAMEPedia or through communication on the mailing list.

If it would not be desirable to discuss the need for a given edit filter on-wiki, such as where the purpose of the filter is to combat harassment by an abusive banned user who is likely to come across the details of the request, please ask using Discord.

If an editor (who need not be an administrator) believes that an existing edit filter is unnecessary, is preventing good edits, or is otherwise problematic, they should raise their concerns on the Administrators' noticeboard or directly with the administrator who created or enabled the filter for further discussion.

Private filters
While edit filter settings and logs are by default publicly viewable, some are set to be private. For all filters, including those hidden from public view, a brief description of what the rule targets is displayed in the log, the list of active filters, and in any error messages generated by the filter. Edit filter managers should take care not to discuss the specifics of hidden filters publicly.

Filters should only be hidden where necessary, such as in long-term abuse cases where the targeted user(s) could review a public filter and use that knowledge to circumvent it. Filters should not generally be named after abusive editors, but rather with a simple description of the type of abuse, provided not too much information is given away.

Filter managers may share the contents of private edit filters with non-administrators on the basis of their good judgment. Be careful not to test sensitive parts of private filters in a public test filter (such as ): use a private test filter (for example ) if testing is required. Similarly be careful not to post sensitive parts of private filters on talk pages or persistent pages of external sites.

Sensitive issues concerning private filters may be raised by emailing filter managers or by contacting them via the discord.

Tools and resources
A watchable page of recent changes to public filters is generated at Special:AbuseFilter/history.

Edit filters sometimes make use of relatively large (though not usually complex) regular expressions (regexes). External tools such as Regex101 can be useful for testing these. Because regexes are extremely fragile and almost any typo in one will cause it to malfunction, use of such a tool is recommended. Use of the test interface when creating or editing filters is also recommended.