Test-time adaptation (TTA) lets an AI system learn or reason while solving a particular evaluation task, using information supplied by that task rather than relying only on fixed parameters. section 19.3.6
ARC-AGI and o3
Every leading ARC Prize 2024 solution used TTA. OpenAI’s o3 model searched or reasoned with substantial test-time compute, scoring 76% at about $200 per ARC-AGI task and 88% above $20,000 per task. section 19.3.6 section 19.5
TTA commonly takes two forms:
- Test-time training adjusts selected model parameters from examples in the test task, typically with gradient descent. section 19.3.6
- Test-time search explores candidate reasoning steps or solutions, including natural-language reasoning and symbolic program synthesis. section 19.3.6
TTA improves flexibility on novel problems, but current gains can require extreme computation. Efficient, human-like adaptation remains unresolved, and brute-force search does not scale reliably to harder tasks such as ARC-AGI-2. section 20.2 section 20.6
