AIAI EngineerJul 31, 2026· 16:30

Ending AI Slop — Thais Castello Branco, Taste Labs

Thais Castello Branco, founder of Taste Labs, argues AI slop persists because subjective domains like design and writing lack the verifiability of code, and ending it requires decomposing taste into measurable components and building preference data that breaks from the mean. She sorts domains along a spectrum from things that verify and execute cleanly to pure preference with no ground truth, showing how brand adherence becomes trainable by decomposing a brand into colors, typography, motion, and textures graded against an original rather than judged whole. She warns that models predicting the most likely outcome collapse to the mean, killing the creativity good design depends on, so Taste Labs works with over 1,000 expert designers to force distribution and create preference vectors that capture pluralism. Her team pairs expert judgment with human QA tied to specific code components, distinguishing disagreement on alignment from disagreement on style, and advocates quality over quantity for subjective domains.

Transcript

Ending AI Slop0:00

Thais Castello Branco0:13

Hello everyone. It's great to meet you all. I'm Thais, I'm the founder of Taste Labs. For those of you who don't know us, we came out of stealth a few weeks ago, and our whole mission is basically: how do we end AI slop?

And we believe that to really solve this problem, we have to first decompose and understand subjective domains,right? I think, as probably all of you know, AI has gotten quite good at things like coding and math, but it's still super behind on things like design, creative writing, personality, emotional intelligence.

And to understand these domains, I think we have to take a little bit of a different approach than we do with, um, with objective ones. So our idea is like, how do we become this data and infrastructure layer to really understand these problems and to become the solution for them across the stack?

So from the foundation model layer, all the way to how do we build solutions for agents as well. So we work primarily in two ways. We work with the top frontier labs on how do we evaluate, benchmark their models, understand where they're breaking, understand how we can fix them, and how do we determine also which problem is better fixed through each method.

So what things should be turned into RL environments, which things should be turned into post-training data problems. But then we also go and work with a lot of agent and application layer companies on what are things that we actually don't believe should be solved at the foundation model layer, and that might be better solved through methods like context or understanding user intent,right?

We're basically betting on a world where suddenly you're going to have billions of people creating that are not necessarily experts. So this understanding of user intent and context is equally as important as how do we get these models to improve.

For today, I'm going to focus on the model training part. For those that are here tomorrow, I'll also be giving a chat on the design track where I'll cover more on what we're doing on the agent side of the house.

But there we go. Okay. So most of the world is subjective, as I was mentioning. A lot of the world is subjective,right? If we talk about these domains of writing, even workflows within companies,right, of sales, marketing, a lot of the times there's this multitude of answers.

There's not one clearright answer, and it's very hard to define what great even means. I think at the end of the day, like, those are why these domains are so difficult. And we oftentimes, I would say, forget to mention, like, why.

Verifiable Code2:29

Thais Castello Branco2:29

We treat, for example, the fact that code is verifiable and measurable as something that is a property about models. And models are great at coding because we've made them great at coding, but realistically it's actually a fact about code.

Code is something that decomposes, it verifies, it executes, and so it makes it a lot easier for us to be able to train on these domains. For something like design or writing, like, how do you decompose it? How do you verify it?

How do you judge if it's actually good? So that's why they become so difficult. So there's two characteristics that I want to touch on today on why fundamentally subjective domains are harder. One is that capability follows measurability. So if we can solve the measurability problem, or at least part of it, then we can solve a big portion of these domains.

The second, which I'll touch on later, is basically this, like, collapse to the mean and why the mean is not necessarily optimal in subjective domains.

Okay.

Decomposing Design3:26

Thais Castello Branco3:32

So to really start solving this problem, we have to turn something that feels fuzzy, like if I ask you, what is great design, into something that is more verifiable. So there's a few questions here,right? Because if I ask you this of what is great design, you could ask yourself, okay,

do you mean great for which type of person, for which type of taste, for which situation? The same slide could be amazing, for example, if you are a startup and completely inappropriate if you are a finance firm. So it's contextual, first of all.

Second of all, it has this property that it changes over time, which is different from other domains. What is considered good today is different than five years ago and different than five years from now. In code, that's not necessarily true, or in math,right?

That's something that is way more consistent over time. So our ability to, again, decompose it and understand how is this good for a specific audience, how is this good today, how is this good in context

is some of the things that we've been thinking about in terms of how to break this down. But I want to give you a very specific example because, of course, this can mean many things. So let's talk about brand.

If you're at a company and you've used coding agents, you've probably shipped an internal dashboard. You've probably shipped an internal, like, landing page. And oftentimes you might wonder, okay, how do I determine if this is slop, if this is actually good?

And you have kind of this secret weapon at your disposal, which is really all the work that probably designers at your companies, for example, put into defining your brand. A brand to define takes a lot of effort, takes a lot of care.

You're defining all these components about it, when it's good, why you're choosing certain combinations of colors, of typography, of spacing, of texture. But if I just ask you to be like, okay, create something great, that's very hard. But suddenly if I'm like, okay, make something that is on brand, that is a much easier problem to define, and a brand is something that can become decomposable.

So for example, if we I'm using the Reducto brand as an example here because I like their website. Let's say that we decompose this brand into the colors, the typography, the motion, the animation, the textures. Suddenly you have these very codified things that you can verify against.

Verifying in general if something is on brand, and you can try this by prompting an LLM as a judge to do it, is quite hard. But once you start picking apart the exact elements that represent what great is, then it suddenly becomes the shape of something that is codifiable and verifiable.

So if you want to turn this into a shape of an RL environment, for example,right, how would you train a model for a capability like brand adherence?

LLMs as a judge might not necessarily always be the best method. We know that there's a lot of reward hacking. We know that there's interesting hallucination patterns there too. And so we oftentimes try to create methods of basically how do we turn a task that feels fuzzy into one where there's a clear ground truth so that it can become the shape of an environment.

So in this case, the task design itself is really kind of the hardest part of the problem of how do you turn something that appears very fuzzy into something that actually can be RLed. And so in this case, that decomposition that I mentioned becomes the ground truth.

So let's say that you start by tasking an agent to create a new page that is going to adhere to the Reducto brand but be completely net new and different. You would want that output to not only be graded versus the original, but to be graded on this ground truth,right?

Because it could come up with completely new ways of using these components that are still valid but are different from the original. So you don't necessarily want to just see if it's replicating the original. So this is one example of, like, how to turn this into a problem of environment shaped so that we can make it more verifiable.

But in a way, all of these things are, I would say, like spectrums,right? You have in a problem like design, you have these elements of things like vision, alignment, typography that are closer to objective. Once you start moving up that scale onto things like style, fit, creativity, how do you judge and measure something like creativity,right?

The Spectrum6:58

Thais Castello Branco7:17

That's much harder. And so you kind of need to think of this as, like, a routing problem of how do you understand this, like, vast fuzzy problem, break it down into smaller components, and what is the best solution for each of these components.

So why does something feel like slop, for example, when we're talking about something like creativity,right? I think this is the second reason why subjective domains are so much harder to solve. Because if we're talking about the properties of models, they're basically predicting what's the most likely outcome to show up next, and they assume that that outcome is the ideal outcome.

Collapse to the Mean7:31

Thais Castello Branco7:49

And for something like math and coding, that is true,right? You want the answer that your model gives you to be the average answer if you're asking what 2 plus 2 is, which also happens to be theright answer and the optimal answer.

But for something like writing or design, you don't necessarily want the average answer,right? The average, meaning the most likely, does not necessarily coincide with, like, the optimal. A lot of, like, what I describe it as a lot of greatness and creativity happens actually at the ends of the distribution.

It's not the most likely outcome. It's when you actually actively break from rules and actively break from patterns that you can create things that are subjective and great. And so the reason why this feels like slop and that we have this feeling that we're surrounded by slop is exactly because of this collapse to the mean and this repetition.

And so we have to find ways of, okay, how do we break these patterns? How do we break from the mean? But in a way that's also intentional. So then you kind of shift the problem onto things that are not so easily maybe verifiable, but that are more questions of human preference and judgment, and that might be better solved by data, for example, than by environments.

And so, again, this kind of, like, mode collapse is really the thing that we're trying to solve in how do we force that distribution back. Oftentimes, by the way, we work, for example, with a community of designers over, like, 1,000 experts that are experts in different types of medium, different styles, and we purposely want to force that distribution when we're breaking down the problem exactly so we don't end up in this mode collapse.

But there's, of course, a lot of other pieces of that puzzle. But I think this is an interesting framework. It's like the closer you are to something that it becomes verifiable, especially programmatically, the better for something like RL,right?

Pulling to Verification9:15

Thais Castello Branco9:27

And I think the challenge is how do we turn things that feel fuzzy into things that become more verifiable by establishing this ground truth and designing tasks in a way that allow for that. But then the more that it does shift to things that are contextual or that depend on that time element that we talked about or this, like, distinction in preference, the more this shifts towards something that requires human judgment.

So

I like this analogy of basically kind of pulling things toward verification. So brand adherence on its own would be something that's very hard and is probably better judged by a human than, for example, by an LLM as a judge or something deterministic.

But by codifying it, by understanding which pieces matter and how do I turn that into something that is observable and measurable, we can kind of pull it into this realm of verification. So this routing logic, as I would say, if you have one takeaway, take this away, is, like, how do we break down this problem into something that you understand what's actually the best method to solve it.

And so when we are talking about these things that are more subjective, we do require human judgment. I think this is something that

Human Judgment10:24

Thais Castello Branco10:33

we believe human judgment is still at a much higher level than any LLM as a judge. And this, like, human taste is really how do we encapsulate this in a way that can be turned into high-quality data so that we can train these models better.

And I think one of the tricky things here is oftentimes in the past, you had kind of this collection of preference data that would collapse, again, to the mean because you would collect it from a bunch of different people without necessarily understanding who they are, what they like, why they like it, when they like it.

And if you don't break up that problem accordingly, you then end up, again, with preferences that kind of don't agree with each other. Because that naturally happens in the world,right? I bet that some of you might like one style better than another.

And that doesn't mean either of those things are wrong, or it doesn't mean that the best answer is the average of what two people might like. It means that we need to fundamentally understand that the world is multi-preference and how do we do that matching accordingly.

So this almost, like, understanding of how do we create, like, a preference vector, let's say, for someone and attach that to even something like preference data can help us to train in a way that allows for that more pluralism of preferences intentionally instead of that data being turned into something that's noisy.

When we talk about data quality as well for these domains, I think it becomes very I don't know if any of you have bought data, for example, for these domains or have tried to curate data yourselves. But it's very hard to define, okay, like, now I'm realming to this side of data.

Data Quality11:41

Thais Castello Branco11:55

What is actually good? What is actually going to be helpful to my model? And there's obviously a few things that are harder to define, but a few that I think become more controllable. And how do we actually understand patterns of quality so that we can measure them?

So one I would say is that problem decomposition. How do we force, like, true distributions of what you see in the world? How do you force true, like, expert selection across these different buckets? And these are things that you can totally control,right?

You can see who those experts are. You can do a selection pattern that is very strict. And you can decompose that problem. And this is something that is completely in your control and that totally helps with the results, let's say, of the experiment being good.

The second is I would say that, like, flow of, like, how do you determine then theright problem routed to theright solution? We also, I would say, do a lot of what we call

essentially, like, QA on this data. And I think there's two ways to do that is understanding what are properties about that data point that correlate with it being rich and high signal. So for example, specificity. When you're trying to ask an expert to define, is this good, is this bad, or put reasoning behind it, or create a whole observation system around how they would judge an asset, the specificity of their language and of how precise they're being able to be with how they're doing that description is what will determine that data quality.

Or for example, if you can tie their commentary with actually which piece in the code does this relate to. Like, let's say you have an expert that's judging a landing page. They might be able to just, like, write a paragraph describing this, but we know that models have a tricky time kind of actually connecting the piece of the code to the visual.

And so if you can find, for example, a method to tie that exact code component to the commentary of the expert, suddenly you have data that is way less noisy and way more clear. So these are some things that we can do both in terms of the flow of how you connect the data, of how you collect the data, but also in these, like, QA checks of how do you determine characteristics about it that will correlate highly, let's say, with valuable data.

Human QA13:58

Thais Castello Branco13:58

And same with human QA. I think, by the way, human QA is tricky here because there's two sides to it. There is a side of, for example, let's say you're collecting a bunch of preference data about slide design.

You could have human QA be like, okay, is this, again, high-quality data? Is it following the specs, which most people would agree on? But suddenly if you ask for expert consensus and you try to have another expert see if they agree with the initial designer's, like, votes, you might start seeing some disagreement there.

And I think the key is understanding, is that disagreement something that's actually a flaw in the data? Meaning, are they, for example, disagreeing on something that they should be agreeing on, such as alignment? Like, alignment is something that's pretty objective.

So it would be kind of odd to see experts disagreeing on that front. But suddenly if they're disagreeing on things like style or aesthetics, that is not necessarily bad data. That's actually good data. It shows you that there is a distinction for what people like.

And so this almost, like, analysis of how do you run human QA in a way that both screens for kind of the fundamentals, but then when you use consensus, I think, in an intentional way is another big, big piece of this.

And then obviously kind of seeing actually how this data is interacting with models. We run a lot of research on our side. Obviously, when you're interacting with labs as we do, there's a lot more involved and we oftentimes don't get that feedback loop of exactly what affected this cause, which is why we're so adamant on focusing on these things we can control in terms of data quality.

Quality Over Quantity15:26

Thais Castello Branco15:26

Because these are things that we can completely measure on our side. So I think one other piece of advice or message of the day is I think especially when it comes to subjective domains, I would advocate for a quality over quantity approach.

I think creating high-quality data is expensive. It's difficult. It takes a lot of understanding and depth around a specific domain. And having that be incredibly high quality done by people that also are incredibly high taste or whatever you want to call it in that domain yields far better results than getting a bunch of noisy data or a bunch of messy data that was not necessarily intentional or didn't have all those things we talked about of, like, the problem breakdown.

So that is my message of the day. Thank you.