Let's Speedrun Costco: Brainstorming With Fable

This module is where we have some fun. We're building Flatbed, a Costco speedrun app I made a few weeks ago for my wife and me. We had a massive Costco order to get through and we're both extremely competitive, so I wanted one screen each, the store split into departments, and a race. I think the creativity is where the gold is, and plenty of real products started as a fun side project (Twitter came out of one), so that's the spirit for the whole module.

This first part is the brainstorm, and it's where the magic starts. I switch Claude desktop over to Fable 5.1, set thinking to Extra and just talk at it. No spec, no code, nothing gets built. I want it to think around the idea with me. Here's the prompt:

I am going to create a fun little application that I can use to speed run Costco, a Costco shopping event. This is designed for, let's say, 2, 3, or 4 people, and the whole idea is that we want to divide Costco out into departments based on how many people are going to be joining. This is supposed to be fun. It's supposed to be highly visual and entertaining.

At some point, I want to plug in AI so it can help us find things. Perhaps we can scheme and strategize in some way. Where I am right now is I am just trying to get inspiration. I'm trying to think around the notion of speed running because it is for me and my friends. My wife is extremely competitive, as I am, and I feel like we could optimize and have a really good time going to Costco together, doing these fun things. So help me think through this. Help me think around it, through it, under it, over it. I'm really focused on the fun angle here. Give me a few ideas. How can we design this? Obviously going to be on our phones. Help me think of things that I haven't thought of.

Before I hit go, I added this to the end:

The last thing I want you to consider is that I am not going to deploy this as a native app on any platform. It should be a web app that I can deploy easily somewhere for free. That is the big one. And the last thing is it should be extremely easy to use for a non-technical person. So easy button presses, the screen should stay up, things like that. Okay. Give me some ideas here. Let's scope this thing.

Fable came back with a mockup (Kirkland eggs, a "Can't find it" button, the works) and I answered with another wall of text. It's loosey-goosey on purpose. We're brainstorming, and the structure gets squeezed out of this later:

I really like the shape of this and I love the speed run angle. Go full speed run on this. As far as the things I haven't hit yet, signal's fine at our Costco. Not worried about that. The screen staying on is okay too. Sync to start: we'll just start together. We don't need to count down. We'll just do it together and hit go. As far as checkout goes, we'll hit stop together. It's not that competitive. As far as the store layout being different, maybe let's go with just a standard Costco layout for now, whatever is the most common one. I don't know how to get a hold of that, so just go with whatever you can find online. Disputes, that's okay. We're going to go with a trust. I'm not going to dial the number up on that. Share card, I like that. That's fine. We'll keep that. No typing during a run: this made me think that perhaps we want some chat in there. "I can't find this. Can you get it for me?" This basically pings the other person in real time, and then maybe we could razz each other too. I'm not sure. What I want for the scope is I want everything. I want to do this in one long run and make it look as gorgeous as I can. As far as AI here goes, I'd like an AI to heckle us and then also to answer questions. By heckling, it watches us as we go, ticking the list down, and maybe heckles the other person saying, "Hey, Carolynn's catching up to you," or whatever. That sounds like fun. Let's tighten this up. Is there anything I am not considering here?

Then I learned a lesson I seem to learn about once a month: be careful what you tell your agent. I finished answering its last round of questions with this:

Good, all of this is great. Let's go with every one of those. That sounds like a lot of fun to me. Hopefully you have enough to go on.

To me that meant "write the spec." To Claude it meant "start building," and with Fable, which is great at thinking things through and not what I want writing code. I stopped it, had it write spec.md, architecture.md and plan.md instead, and we talk about how much ceremony a fun little app actually needs. Next up: guardrails, so we're not vibe coding a mountain of garbage.

The grill-me skill I mention is Matt Pocock's: aihero.dev/skills-grill-me.