Here's a constructive solution I managed to collect from different people. To keep it simple and straightforward I'm dividing each suggestion into parts:

Overall Idea
- It's better to scrap the idea of having a uniform rule if it's going to be adapted it as an entity. The best course of action would be to give the server owners freedom to manipulate the rules since there are different kinds of CTF. There's one where you can physically carry the flag back to your base and the other one only needs you to stand inside the flag zone to continuously mine points. A tickable box to control the rules of these two different variations opens up a lot of possibilities.

The Flag Entity
- Functionality-wise this should be made to be simple. A colorable flag pod with a floating scoreboard on it to count how many points did that pod get. Wiring or connecting pods with each other using a connector tool (There might be better ways) recognizes them as the teams involved in that game or round. Holding or pressing E on it colorizes your model with the pod's team color (Can only be done if the round hasn't started yet). Typing "!start" in chat and then getting a "!accept" response from every player who pressed E on the involved pods starts the game. Once a round starts, outsiders will be ghosted and are unable to damage or bump into any of the players involved. This way there can be 2 or more separate CTF games ongoing in a single big map. It's also possible to have one flag pod in a DarkRP server and whoever maintains the position gets to mine money every 15 seconds or so. It's one of the few possibilities that can certainly work.

The Spawnpoint Entity
- Now there are so many ways to do spawning. Let's list them down:

1. Spawning through entities or spawnpods.
The simplest solution. Spawn using an spawnpod with a set time of invulnerability (Like 15 seconds) in case of spawn killing issues. Two or more spawnpods can be involved and connected to a flag pod.

2. Spawn right next to your flag pod.
Basically the same as the first one, but even more simple. No more connections involved.

3. Random spawning in the entire map.
Very self-explanatory. Puts everyone on equal grounds.

There are lots of ways to do this but so far this is what I can come up with that's actually reliable.

Notifications and Other Miscs.
- This can be done with either popup notifications whenever someone steals the flag off of your team or if someone finally scored and brought the enemy flag to the other. Chat notifcations can also work like typing "!score" as someone who's involved in that said round gives you a text or update of the score. This way no HUD or other third party shenanigans are involved.

That's all for now. Some of them might not work as intended but it's a solid ground to stand on if you're pushing the adaptation. Good luck with it!

Ok, so it sounds like what we're actually aiming for, is not just flag entities to interact with, but a CTF addon that manages teams, spawning, and flags. Though, unlike the gamemode, it probably won't control win conditions.

I think it would be better if, instead of having people join teams by running up to the flags and interacting with them, teams were instead handled through a menu. That same menu could also present options to admins for things like capture style, spawn style, and flag manipulability.

Unfortunately, the problem with having a single capture point that earns money for the capturing player in DarkRP is that money is a concept specific to DarkRP, and this addon would have to directly search for and attempt to modify the money of DarkRP. Why should one third party gamemode get special acknowledgement, when it's impossible to acknowledge them all? It's probably also unrealistic to expect me to go in and add an exception everytime someone wants to support a new mod (this is a hobby project, after all).

I guess I'm a little confused on what all you want this hypethetical addon to control. Are you expecting some sort of match management, with win conditions and restarting? If so, that's why it was made as a gamemode in the first place. For example, what does it mean to have a CTF win condition if the addon is loaded on top of Prop Hunt, which has its own teams, rounds, and win conditions?

One last thing: What is there to gain by having 2 CTF matches in the same map? If they're not supposed to be interacting with eachother, then is it any different than being on seperate maps?

I don't mean to be a naysayer, I'm just trying to figure out how CTF could be made into a stand-alone addon that still adds something if placed with other anonymous gamemodes.

Right now it's only a big block of ideas put together. There are better ways out there that we're sure you know as the one who does the coding side of things so you can probably take what is good and not good among what we shared above to make the best functionality.

First as for the DarkRP suggestion, what I considered before is if it really does become an entity it can be used later as an event tool for DarkRP sorts of stuff. Still it's only one of the ways on how it can be used since it'll be an entity but it's probably best not to think about this one for now so we can get to a good consensus which is to make it into a working entity minigame.

As for other gamemodes like Prop Hunt, it probably won't work like you said. But we can never tell since people can think of really fun things out of ridiculous ideas. That's how creative this community is right? How they use it though shouldn't be the concern of the addon. It's probably best to focus on the main functionality fully supported on Sandbox.

So long as it's going to have flexible rules as a game enity it should be golden. Having menus to run it is actually a clever idea and I really like where this is going.

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Of course it should still have the win conditions like:

Win by reaching <-llllllllllllllll-> 300 Points ✔ (Tried to make a slider lol)
Win by capturing all flags ✔
Win by eliminating all enemies (No respawning) ✔

And as per usual you can handpick whatever is good with these suggestions. Just use whatever is usable.

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Having 2 running CTFs will probably complicate things even more so we can probably scrap that, that was only made into a suggestion thinking of how will outsiders be treated when it does become an entity. I guess the server owner can infract them instead if an outsider tries to meddle with an ongoing game in Sandbox.

That should save you some trouble of thinking ways to implement things. Hope it helps.

Win by reaching <-llllllllllllllll-> 300 Points ✔ (Tried to make a slider lol)
Win by capturing all flags ✔
Win by eliminating all enemies (No respawning) ✔

As for "Win by eliminating all enemies", I was thinking if just in case someone wants to add that win condition on top of having all the flags captured as the main win condition sounds like a good detail to add.

Feel free to scrap if it's awful.

Lol, deaths in GMod are so fast and frequent, I think a Last Man Standing version would make for some *very* short matches. If the idea is as a minigame in sandbox, then what actually happens when a match is won? Pops up the "Congrats" image, then simply reverts to the out-of match state? Unlike the gamemode, should there be no difference between active and non-active match in terms of general gamplay? (Like how durring the combat phase there's no access to the physgun or toolgun)

For players who aren't on a team you could do several things: A) Auto assign them to a team to create a good team distribution. B) Let them keep doing their thing, but disallow flag pickup. C) Force them into spectator mode.

Another option we have available, is instead of doing an addon that manages matches, I can simply provide flag bases that are spawnable from the menu that constrain themselves so that there's only one flag per skin. Then use some sort of psuedo team system, where something like the first flag you touch marks that flag as your home flag until it's removed, and then captures are displayed on the flag base, and that's litterally all the addon does.

Such a simplified system may not be desirable, though, but I feel it fits the idea of "sanbox version" more. If people want to play a full CTF match, that's what the gamemode is for, you know?

Yeah I think the ideas we have so far is all good now.

tell me the commands for this mod

So can you make other game modes?

Pls fix simphys vehicles