Commentary (there will be a lot of "to me"s because I have been a bystander to this exchange so far):

I think this post misunderstands Holden's point, because it looks like it's still talking about agents. Tool AI, to me, is a decision support system: I tell Google Maps where I will start from and where I will leave from, and it generates a route using its algorithm. Similarly, I could tell Dr. Watson my medical data, and it will supply a diagnosis and a treatment plan that has a high score based on the utility function I provide.

In neither case are the skills of "looking at the equations and determining real-world consequences" that necessary. There are no dark secrets lurking in the soul of A*. Indeed, that might be the heart of the issue: tool AI might be those situations where you can make a network that represents the world, identify two nodes, and call your optimization algorithm of choice to determine the best actions to choose to attempt to make it from the start node to the end node.

Reducing the world to a network is really hard. Determining preferences between outcomes is hard. But Tool AI looks to me like saying "well, the whole world is really too much. I'm just going to deal with planning routes, which is a simple world that I can understand," where the FAI tools aren't that relevant. The network might be out of line with reality, the optimization algorithm might be buggy or clumsy, but the horror stories that keep FAI researchers up at night seem impossible because of the inherently limited scope, and the ability to do dry runs and simulations until the AI's model of reality is trusted enough to give it control.

Now, this requires that AI only be used for things like planning where to put products on shelves, not planning corporate strategy- but if you work from the current stuff up rather than from the God algorithm down, it doesn't look like corporate strategy will be on the table until AI is developed to the point where it could be trusted with that. If someone gave me a black box that spit out plans based on English input, then I wouldn't trust it and I imagine you wouldn't either- but I don't think that's what we're looking at, and I don't know if planning for that scenario is valuable.

It seems to me that SI has discussed Holden's Tool AI idea- when it made the distinction between AI and AGI. Holden seems to me to be asking "well, if AGI is such a tough problem, why even do it?".