Is it a good idea to show a warning to users who are typing tags incorrectly?

Question

On our site, we have a tag field that looks like the following:

Today, while looking at some of our users interacting with the site, I noticed that one of them had used only spaces to separate their tags, instead of using commas as the input field advises (he probably did not see the advice and applied his idea of how tags should be typed in).

This raised a concern: are we going to get many users that fail to read the advice and end up typing in tags by only separating them with spaces (which would lead to having a huge single tag) and if so, should we try to do something about it by educating the user about the problem?

I thought that we could make the field detect if the user has entered no commas in the field and check for the presence of more than one space, and if the condition is met display a warning that would say something along the lines of "You might be typing in your tags incorrectly. Are you using commas to separate them?".

If we didn't tell our user about this issue they would probably have a hard time noticing and correcting the issue after submitting their entry, because the only difference between well-formed tags and "huge chunk" tags is the amount of space that goes between them, a thing which a novice and uneducated user might miss.

Is it a good idea to try to prevent this behavior and try to educate the user a priori? Are we taking the right approach?

Answer 1

One way to guide the user would be to style the tags as soon as the users finish typing a tag, thus indicating that the application/system has recognized their tag.

For example, when the user types in the tags that you have entered for this question i.e. "user-behavior", "tags", "warnings", this is what people typically do.

Instead, try the following. As soon as they type a comma, change the styles of the text to indicate that the word(s) has been added/recognized as a tag.

And most importantly, provide clear instructions above the textbox on the accepted delimiter for the tags. It makes it more readable. When people see textboxes, they start typing right away. It's natural behavior since the user feels invited to respond when there's a call to attention especially with a cursor blinking at them.

And if you have watermark/placeholder text in that box that disappears as soon as the user starts typing something, then the user can't remember what the instructions were.

Finally, highlighting the instructions about the delimiter in the guidelines can play an important role too as it grabs the user's attention by providing contrast to the surrounding content.

Answer 2

1) What Girish said would be my first port of call

2) How many people are doing the 'wrong' thing? Maybe you need to reconsider whether not allowing spaces as separators is the best option? How many people are actually using multi-word tags compared to the number of people making mistakes? Can you support the multi-word tag folk in other ways (hyphens rather than spaces for example)?