Wikipedia:Edit filter

From Wikipedia, the free encyclopedia
The edit filter manager logo.

The Edit filter is a tool used to allow trusted users to set specific controls on user activity and create automated reactions for certain behaviors. Edits that trigger an edit filter are listed in a log by default, but each filter can be extended to perform various actions such as tagging the edit, warning the user, or disallowing the edit entirely.

The Abuse Filter extension was developed by Werdna with support from the Wikimedia Foundation, and went live on the English Wikipedia in March 2009. As of July 2009, nearly all user-facing elements of the filter refer to it as the "Edit filter" as not all the edits it flags are abusive. In the software and special pages it retains its original name.

The extension provides a domain-specific language with which authorized users can specify automatic filters/heuristics to be applied to all edits. Specific rules can be developed, such as "users with fewer than 500 edits are blocked from moving pages to titles which match this regular expression: /po{2,}p/". Of course, the rules can get quite a bit more complicated.


Edit filters should primarily be used to target harmful edits with the aim of stopping vandalism and abuse of the encyclopedia. Problems on a single page might be better served with page protection, and problems with page titles or link spam should be handled with the title blacklist and spam blacklist respectively. Additionally, since edit filters check every edit in some way, filters which aren't tripped more than once every few weeks are usually not considered useful, though this isn't a hard rule.

While filters are by default publicly viewable, some are set to be private. For all filters, including those hidden from public view, a brief, general summary of what the rule targets will be available, and displayed in the log, the list of active filters, and in any error messages generated by the filter. It is expected that filters will only be hidden if necessary, such as in long term abuse cases where a user may read the filter to understand how to circumvent it. The community expects that unless absolutely necessary, filters should remain visible.

Implementation of AbuseFilter on Wikipedia is done with due caution — almost all abuse filters should be tested (in "log only" mode) for at least a few days, if not longer, before being brought to full force ("warn", "disallow", or "throttle" modes). If the filter is receiving more than a very small percentage of false flags, or is designed to catch good faith edits, it should not be placed in 'disallow' or 'throttle' modes.

User right[edit]

Only members of the edit filter manager group are allowed to modify the filters and view hidden filters, and this group is assignable by administrators. Administrators are welcome to assign the right to themselves if desired.

The assignment of the edit filter manager user right to non-admins is highly restricted. It should only be requested by and given to highly trusted users, and only when there is a clear, demonstrated need for it. Demonstrated ability that one can and will safely use it is absolutely critical. This is because widespread disruption of the entire encyclopedia can easily occur—even unintentionally—with the smallest of mistakes in changing edit filters. Therefore, demonstrated knowledge of the extension's syntax and confidence in understanding and crafting regular expressions ("regexes") is absolutely essential. Non-admins should consider helping out at requested edit filters and troubleshooting at false positives to help demonstrate these skills.

Requests for assignment of the group to non-admins can be made at the edit filter noticeboard, where a discussion will be held for up to a week before a decision is made.[1]

Disabled features[edit]

When the extension was initially installed the community decided against enabling the block, rangeblock and degroup actions for use on this Wiki. Admins wishing to block users for triggering the abuse filter can use the {{uw-efblock}} template.

See also[edit]


  1. ^ Process informally agreed upon when Cobi (talk · contribs), who was not an admin at the time, was granted the user right in this thread: Wikipedia talk:Edit filter/Archive 3#Abuse Filter editors group membership request. Discussion may extend beyond a week if appropriate consensus, or lack of it, is not clear.