I just want to chime in and say that this isn't a problem (unless you don't trust your DM to make these decisions fairly, and that's not really a "rules" problem). Not only that, the DM is both allowed and encouraged to make such decisions, per the rules in the DMG.
Folks here in this thread (and elsewhere) often cite this as a flaw or problem to be avoided/overcome/corrected. Maybe it is, maybe it isn't, but it's consistent with the 5E D&D rules...it is what the devs intended.
I mean, it's not a problem unless it's not your preference. It's not how I prefer to GM, not is it how I prefer other to GM when I play, even if I accept that it may happen.
The earlier days of D&D were less filled with the "ah, just do what you want" type of ethos that's present in 5e.
Okay but the GM deciding something isn't railroading
I don't think I implied that.
I provide you guys with the tools and procedures I use. But I also clarify that they aren't prescriptive (just as Rob has). I don't think there is any lack of clarity on how I run a sandbox. I just put out content that is open enough that a different GM can apply the tools to their own approach. I don't think every sandbox has to run the same, but there are basic ideas and parameters to them: open world adventure, a place to explore, the players being able to take initiative and steer the adventure through their actions, a sense of things being alive and dynamic (i.e. the world and NPCs are not static), having a variety of tools like encounter tables, event tables, generators, travel procedures, etc. Again, sandbox isn't attempting to reinvent the wheel. It isn't saying: this is a whole new game. It is saying this is an open approach to running an RPG. People can of course quibble, and debate. I don't own the term, and I think this is just how I look at it. But me and Rob have given you guys example after example, procedure after procedure, and all I can see is responses that we aren't answering your questions (and maybe that is true because you seem especially focused on the very incremental details of the interactions between the players and GM and we are not; and on having consistent procedures from table to table, and I think we aren't). Other posters have done the same. We aren't just giving you hot air. But if you looks at our stuff, we are offering up pretty clear approaches and procedures that we generally follow, as well as principles about rulings and such. We just generally refrain from saying "this is how it has to be done or it isn't a sandbox" and I have a particularly fluid and evolving approach where I am experimenting from one campaign to another with new procedures and tools.
But check out my the good sandbox + thread and you will see I post a lot in there about what I do (I already know fro responses there are people for whom this is inadequate but I think I gave enough information for most people to get how I approach things). Just keep in mind that is a + thread and it is for sharing sandbox not having another one of these debates
Generally, you answer in very vague ways about what you do. It gives the impression that there are not set processes you use. That there is a lack of consistency in the way rules and processes are applied.
What I think would be best is if you took an actual example of play and then described the actual processes used to facilitate that bit of play. Rather than talking about things in a very general way that kind of amounts to "Well, I see what's relevant and then I consider what would make sense in the setting and how the world responds to the players, and maybe I'll use some dice" kind of comments.
You by no means have to do so... but honestly, the lack of specificity makes it seem like you're just deciding in any moment what to do rather than that you have established play processes.
I don't think you need a whole lot beyond the GM asking the players what they want to do, and if the players say they want to go anywhere, or do anything, even if it doesn't seem particularly like it would be fruitful for adventure, the GM says "Okay let's see what happens".
See I don't think a sandbox is about "going anywhere or doing anything". I think that's such a broad idea that it makes the term lose its heft.
A sandbox, to me, is a bounded area of play. this is where things will be happening. What will be happening? Well, that's largely up to the players, though probably not entirely. The GM likely has some ideas, as well... especially at the start of play. Or the game or genre may present certain expectations for play.
What procedures specifically the GM uses there will vary from game to game, and even GM to GM, but the core idea is being open to going anywhere or trying anything, and of course there are some assumptions (like you expect a setting map, location descriptions, etc) but those assumptions I think are flexible points.
See this is what I mean... most of your comments about it are like the above.
What is it that YOU do? Specifically, what do you do? If you're starting a game of Wandering Heroes of Ogre Gate... how do you begin? How do you get the players to drive play?
Like I said, if someone asked this about my game of Spire, I could talk about what I did for that game specifically. I wouldn't talk about making organic decisions or making sure that my decisions make sense and all that general stuff. I'd talk about what I did in that game as GM.