Thais Castello Branco

Thais Castello Branco is the founder and chief executive of Taste Labs, an AI research and infrastructure company developing human judgment in subjective domains such as design. Her premise is that generating more content is easy; making it original, appropriate to its audience, and faithful to a particular creative identity requires fundamentally better evaluation and training.

Raised in Brazil, Castello Branco studied economics at the University of Chicago and worked in brand strategy at a New York technology startup. She joined the Latitud Fellowship in 2024, pursued an earlier startup, then became an early employee at Exa, where her work included Websets, marketing, and data partnerships.

She subsequently founded Taste Labs with initial backing from Latitud. The company launched publicly in 2026 with $18.5 million in seed funding, co-led by Amplify Partners and CRV. Its work includes model evaluation, specialized training data, reinforcement-learning environments, and tools that help application developers account for user intent and brand context.

Turning taste into usable infrastructure

• Creative quality can be measured without making everything identical. Castello Branco breaks brand identity into attributes such as color, typography, spacing, motion, and texture. Those characteristics provide measurable criteria for verifiable brand adherence, allowing reinforcement-learning systems to assess whether new designs fit a brand without requiring copies of existing work. She cautions that general-purpose model judges can hallucinate or encourage reward hacking.

• Average outputs are often the wrong creative target. Whereas a widely agreed answer can be desirable in mathematics, statistically typical designs or sentences tend toward sameness. Her manifesto on judgment examines how model objectives and aggregated feedback can produce creative mode collapse, suppressing the distinctive styles that make creative work compelling.

• Expert disagreement is sometimes a feature. Designers disagreeing about alignment may expose an error; designers disagreeing about minimalist versus maximalist aesthetics may simply have different, legitimate preferences. Castello Branco favors expert preference data that preserves those distinctions and connects criticism to specific visual or code elements. Programmatic checks handle objective properties, while contextual questions remain with knowledgeable human evaluators—a distinction she develops in her AI Engineer talk.

In August 2026, Castello Branco announced a Taste Labs research fellowship focused on model creativity and human preferences, offering access to compute, custom data, designers, researchers, and a stipend.