Raising the 25 chars limit for tags

Question

I just tried to add a tag for "implementation-defined-behavior" on SO but I couldn't because of the 25 char limit. I had to resort to an abbreviation (implem.-defined-behavior), which is rather ugly and to some extent thwarts the purpose of tags, i.e. easy indexing.

Although I acknowledge that too long tag names could be unwieldy, sometimes there are technical terms that cannot be abbreviated in any useful way (especially when there is no widespread acronym).

Could an increase of that limit be considered?

EDIT

This is to respond to all the comments addressed at me that were triggered by the recent news brought up by @Shog9 in his answer.

Shog9 announced that the limit was raised to 35 chars network-wide, thus some people asked me to accept his answer instead of that of hildred's.

TL;DR:

Sorry but, no, I won't accept Shog9's answer. Although I find the change very welcome, I think it is still somehow a sort of a patch for the SE network as it has evolved. A complex system such as SE network is now could well afford another mechanism vetted by high rep users/mods on per-site basis.

More explanation:

I really welcome the change, but this solution would have satisfied me at the time I originally posted my question. After all, 35 chars is probably a reasonable limit for a site like SO, or EE.SE where I'm currently active and committed.

At that time, IRRC, the SE network was still very young and there were very few sites on the network that rivaled SO in quality and traffic.

But time has changed since then, and there are sites that have greatly improved and that have the potential of outperforming SO in traffic (after all, there are more people watching TV or practicing mountain walking than programmers out there!).

Given how SE network has evolved, I still think that the right, long term, solution is option #5 in hildred's answer: in short, allow much longer names under the supervision of mods and as a new privilege for high rep users.

Abuse is always a possibility, even with shorter tag names or for other facilities of the sites. I don't see why, apart from some technical reason related to the structure of the system, hildred's solution (or kind of) could not be implemented with the same level of safety/security as other facilities.

There are sites, as it was shown by others, that desperately need a much higher tag length limit, if tags are to be useful for them.

As the name of something increases in length, meaningful abbreviations start to become unintuitive and not unique, hence you cannot expect people to gain any convenience when searching for an abbreviation they don't know about or that they must guess.

In the end, as on of those sites grows, the problem becomes ever worse, because funny abbreviations, with lots of still funnier synonyms, increase, rendering the tag system unreliable and inconvenient.

Answer 1

I can see the value of longer tag names in some contexts as noted by Giles. So there are a number of courses of action possible:

1. No change: simple, but does not really fix natural-language-processing.
2. Increase to 27 chars: fixes one specific problem, but both makes it more difficult for SO and does not help SFF if someone were to want to tag questions about John Joseph Adams book the-improbable-adventures-of-sherlock-holmes (44).
3. Change this on a per site basis: This has the advantage of tuning it to the subject at hand so SO would be 25, CS at 30, and SFF at 50 (numbers subject to improvement by picking a source other than thin air). But this does not help with the the fact that in most cases long tag names can be improved and shortened.
4. Make long tag names require high rep or a moderator to create or approve: those with create tag privilege can create tags up to 25 chars long, Anything else would be discussed on the site meta and placed by a high rep user or a placement attempt would go into a approval queue. This can be a new privilege or just lumped in with moderator tools.
5. My favorite, combine options 3 and 4 so that the length limit on tags is site specific and can be bypassed by moderators and high rep users as needed on a case by case basis.

Answer 2

Thunderforge makes a compelling argument that the tag length limit should be longer than 25 characters.

Tim and animuson are quite right that shorter tags are generally better; regardless, supporting arbitrarily long tag names is out of the question for the foreseeable future - there are too many things that would break, that people would intentionally break. I guarantee you, the minute we were to allow 100-character tags some jackass would make a new programming language named bwaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaargh and CodeGolf would make it the topic of 80 new questions and everything would go to hell...

...But there are clearly quite a few legit, not-at-all-trolling uses for tags that run from 26 to 35 characters. And as luck would have it, the system tolerates 35-character tag-names as of a year or so ago.

So as of this afternoon, the maximum length of a tag name is 35 characters on all sites. Use those extra 10 characters wisely!

Answer 3

Further evidence that the 25 character limit is a problem on multiple sites

The current bounty for this question says:

The official staff answer is that there is one case where this is unnecessary, but it has been repeatedly pointed out that there are many cases where this is necessary.

To add evidence to there being many cases where this is necessary, below are actual meta posts about tagging things whose proper names exceed the 25 character limit and have no obvious short versions:

Anime & Manga

• Anime de Wakaru Shinryounaika (29 characters)
• Stella Jogakuin Koutou-ka C³-bu (33 characters)
• The Irregular at Magic High School (35 characters)

Board & Card Games

• Battlestar Galactica Pegasus (28 characters)
• Arkham Horror Curse of the Dark Pharaoh (32 characters if you remove "of the")

Gaming

• Need for Speed Most Wanted (30 characters)
• Spider-Man Shattered Dimensions (26 characters)
• Lightning Returns: Final Fantasy XIII (37 characters)
• El Shaddai Ascension of the Metatron (29 characters if you remove "of the")
• Binding of Isaac Afterbirth (27 characters)
• Ratchet & Clank All for One (25 characters, but & is not allowed in tags and ratchet-and-clank-all-for-one is 29 characters)
• Plants vs Zombies Garden Warfare (32 characters)
• Kiss Psycho Circus The Nightmare Child (38 characters)
• Space Invaders Infinity Gene (28 characters)
• The Chronicles of Riddick: Escape from Butcher Bay (38 characters if you remove "the", "of", and "from")
• And many others…

Literature

• Zen and the Art of Motorcycle Maintenance (41 characters, 30 if you remove "and", "the", and "of")

Movies

• Godzilla Against Mechagodzilla (30 characters)
• Much Ado About Nothing (1993 version) (much-ado-about-nothing is 23 characters, currently using much-ado-about-1993)
• The Girl With the Dragon Tattoo (Swedish version) (currently using dragon-tattoo-se)
• Captain America: The Winter Soldier (30 characters if you remove "the")

Portuguese Language

• diferenças-transatlânticas (26 characters)
• questões-transatlânticas (26 characters)

Role Playing Games

• Doctor Who Adventures in Time and Space (33 characters if you remove "in" and "and")

Science Fiction & Fantasy

• Teenage Mutant Ninja Turtles (28 characters)
• The League of Extraordinary Gentlemen (33 characters if you remove "the")
• Captain America The Winter Soldier (30 characters if you remove "the")
• Guardians of the Galaxy vol. 1 (29 characters, same for vol. 2)
• Do Androids Dream of Electric Sheep (35 characters, 32 if you remove "of")

Software Engineering

• Natural Language Processing (27 characters) (SE has since then settled on nlp, but Computer Science has reluctantly kept natural-lang-processing and Code Review has natural-language-proc.)

Stack Overflow

• Cryptographic hash function (27 characters, so the solution was to have cryptographichashfunction)
• NSFetchedResultsController (26 characters, so the name was truncated, which confused people)
• PresentModalViewController (26 characters, so presentmodalviewcontrolle, which is missing the last letter, was chosen)
• Windows Identity Foundation (usually shortened to wif)

Unix & Linux

• Windows Subsystem for Linux (27 characters)

In pretty much all of these cases, an inferior equivalent with heavy abbreviations or missing letters had to be chosen in order to get around the hard-coded 25 character limit.

I shouldn't have to create a silly tag because PresentModalViewController or Teenage Mutant Ninja Turtles is too long. Please increase the tag character limit so that we can avoid these issues!

_{Anyone can feel free to edit this post if you know of more sites that have had meta issues brought up due to the 25 character tag limit}

Answer 4

While I'd support longer tags when moderator-approved, at the very minimum I'd like to see an error message when searching for a tag that is too long.

As an example, here's one that tripped me up for quite a while. If I search for datacontractjsonserializer on stackoverflow, I get results stating 0 questions tagged:

However, in reality there are 119 questions relating to DataContractJsonSerializer on stackoverflow - but they are tagged datacontractjsonserialize. It took me a while to realize that such a tag even existed, since the more natural datacontractjsonserializer is only one character too long.

Can the tag search results be modified to indicate that the tag being searched on is too long? Better yet, if there is a valid, known tag of 25 characters in length whose first 25 characters match the searched tag, can the results include a suggested redirection to the shorter tag?

(Update - Now that the limit has been lifted, I've introduced the tag datacontractjsonserializer on stackoverflow and have retagged the old questions.)

Answer 5

It looks like the Stack Exchange staff may have had a change of heart.

The maximum tag length for Literature SE was increased to 32 characters on June 12, 2017.

This can be increased, but only up to a maximum of 35 characters.... [I] increased the allowed length to 32
_-Shog9

In the comments, Shog9 explains that this is currently not a network-wide change, and that Literature SE is being used as a testing grounds for increased tag character limits.

It's not network-wide... [let's] try it here for a little bit & make sure nothing breaks unexpectedly. The only other place this has been changed from the default is the Russian-language Stack Overflow, and there are a lot of other differences there too - so this is the first time it's been changed on an otherwise-standard English-language site. Also, 32 is a nice round number.
_-Shog9

Answer 6

There is always a better way to tag something than using an atrociously long tag name and without using silly abbreviations which are even worse and extremely hard to find in the tag suggestions.

For your specific case, I would just drop one of the words. Possibilities:

• defined-behavior
• implementation-behavior
• implementation-defined

Just make sure it gets a tag wiki and excerpt that clearly defines the tag's purpose.

If you're ever unsure about how a tag should be created due to the character limit, come to Meta and ask the community to help you. But increasing the character limit just isn't a good option.

Answer 7

IMHO tags must be as short as possible, for readability, usage, and create exceptions to the rules can lead to abuse...

it-seems-this-tag-is-now-wrapped-in-mobile-app-but-still-not-on-desktop-notagoodidea-notagoodidea-notagoodidea-notagoodidea-notagoodidea-notagoodidea-notagoodidea-notagoodidea-notagoodidea-notagoodidea-notagoodidea-notagoodidea-notagoodidea-notagoodidea

Concerning your specific case, I don't know what would be the best, but I really think @animuson suggests you valuable possibilities.

EDIT

• If the tag cannot be written in a concise manner, then it should probably be part of the title instead.

• there are some sites that do not respect this rule? Ask to fix those sites instead of wanting increase the limit in the others.

Answer 8

If you're wanting to exceed the maximum character limit for a new tag, experience has taught us that you probably want to re-think the tag and see if it can be broken out into more than one. Animuson suggested some good alternatives that could be used interchangeably and applied to a broader range.

Remember also that tags are candidates for inclusion in the title of the page when viewed, so the constraints are as practical as they are philosophical. Raising the limit here would be a little self-defeating in both aspects.

Others have noted that what you were trying to create is a meta tag and I don't think this is the case. The term oddly specific comes to mind, but that just points to the fact that the tag would be more useful if split into several.

And please, whatever you do, don't invent a programming language with a name that exceeds 25 characters or I'll have to eat this status-declined with salt & pepper.

Answer 9

The tag you want to create is Meta Tag. Tags should be used for technologies or libraries involved in questions. Such 'canonical' tags don't tend to be so extremely long, so the limit is actually doing what it is supposed to do.

Tags should be used for tags and not for descriptions. This is what Jeff's post is about.