Please add an accurate count for how many episodes characters actually APPEAR in.

Could you provide an example of where being credited vs. appearing in creates confusion. ....

Whether significant "confusion" exists may be debatable, but we can readily find many examples to illustrate the issue in question.

Here is one such example:

In the cast list on the title page for Sense8 (2015), we see that Daryl Hannah is listed as credited for 12 episodes:

 

Although that number is presumably accurate, In most of those 12 episodes Daryl Hannah did not appear but was merely credited.  Indeed, most of those credits have the "(credit only)" attribute.  Currently, that attribute appears for 7 of those 12 credits, leaving 5 without that attribute.  (Some sources had said Hannah was to appear in just 3 episodes but I'm not certain if that's the accurate number.)

Anyway, the point of this example is that such credit lines in series cast lists don't provide any immediate indication of the number of episode credits that do not have the "(credit only)" attribute.  Depending on the accuracy of the data, that number would indicate the number of episodes in which the actress is believed to have actually appeared.

Nobody,
Thanks for the clarification and example! I'll investigate the issue and report back...

Do their names appear in the regular on screen credits? If so, episodes they are credited for, but don't appear in, can have the attribute "(credit only)" added.

yes they do, your suggestion is fine, they need to figure out how to show both numbers.