How far down the rabbit hole do you want to go? That's kind of what this turns into.
Software & tools
software seems to be pretty clearly things that could fit comfortably in tools, as it's almost entirely about some kind of tooling. Hell, "tools" is the second word in the description of software, and "software" is the third word in tools. They're pretty clearly overlapping heavily.
On top of that, if you look at gm-tools, you'll see software and tools being used interchangeably on a lot of questions in combination with gm-tools.
On the surface this seems somewhat reasonable, as GM tools may not overlap very well with player tools. The problem is that gm-tools doesn't do a very good job of dividing things up by topic. Looking at gm-tools questions, you also see a bunch of other tags, such as map-making, gm-techniques, campaign-development, generator, and in the case of a question like this with gm-preparation, where gm-tools isn't related to tools at all. You'll also find quite a few also tagged with software or tools.
Given that, I'd also create a synonym for gm-tools to tools, and let the more specific tags like map-making let people find questions related to a specific type of tool. This is also going to work for tools that are of interest to players and GMs, like character generators, without raising more questions like "is that a tools, or gm-tools question?"
online-resources is actually being used for two things at once. One of them is yet another version of tools, only online. Like this. Or this. Unsurprisingly, tools and software show up along with online-resources quite a significant number of times. Even when it's not there, a lot of tools questions are given answers for online tools.
The other use is for online versions of printed material.. Or web enhancements to printed material.
I don't think these two things have any business being together, as they really have no relationship and having them in the same tag doesn't help organization at all.
In the first case, they should be retagged tools. In the second case... does anybody find that second case useful? I can't decide if it's worth keeping or not. Right now I'm leaning towards no, as "online version of a book" really isn't something I feel needs a tag.
The tools tag description is this:
A device, software, procedure or process used for a specific purpose
in relationship to roleplaying games.
The software one is this:
Applications, tools and utilities which assist in character creation,
combat management, or DM/GM organization/preparation.
The current tools description is entirely accurate, but not the easiest language to parse. I prefer the software one, as it's very clear on what it's trying to be. Given that, I'll throw out a rough suggestion for a combined wording for tools. This needs more work, but it's something to discuss.
Software, devices, or procedures to assist in character creation,
combat management, GM organization/preparation, or game play.
Summary - Steps to take
- tools - Keep as is.
- software - Make a synonym of tools.
- gm-tools - Make a synonym of tools.
- online-resources - Go through the 58 questions with this and retag the ones that aren't about online tools to something more appropriate (like a tag for the relevant game system). Then make a synonym of tools.