All multivalue parameters have this limit. Perhaps that should be noted somewhere in the autogenerated help. I do believe this is already documented in the mw.org docs.

• Bug 32499 has been marked as a duplicate of this bug. ***

titles in action=query should be another.

(In reply to comment #3)

titles in action=query should be another.

Hmm it's just what was said in the duplicated bug

beau wrote:

This information needs to be available through API too (not only in help). I always use limit=max, because some scripts run under bot account and some not. I am unable to do that for titles= parameter, because I cannot fetch that value using for example meta=userinfo.

The PARAM_TYPE for this params are not set. With bug 28254 code was added to action=paraminfo to handle the missing type. You can add this code also to action=help to get the right type. With a type the information is displayed. At the moment this is under a condition, which check the $type (ApiBase::makeHelpMsgParameters). Another solution is to move the text out of the condition.

a possible fix commited with gerrit 4061

successfully merged by Hashar