Learning Task Representations from In-Context Learning
Baturay Sağlam, Xinyang Hu, Zhuoran Yang, Dionysios S. Kalogerias, Amin Karbasi · 2025
Large language models (LLMs) have demonstrated remarkable proficiency in in-context learning (ICL), where models adapt to new tasks through example-based prompts without requiring parameter updates.However, understanding how tasks are internally encoded and generalized remains a challenge.To address some of the empirical and technical gaps in the literature, we introduce an automated formulation for encoding task information in ICL prompts as a function of attention heads within the transformer architecture.This approach computes a single task vector as a weighted sum of attention heads, with the weights optimized causally via gradient descent.Our findings show that existing methods fail to generalize effectively to modalities beyond text.In response, we also design a benchmark to evaluate whether a task vector can preserve task fidelity in functional regression tasks.The proposed method successfully extracts task-specific information from in-context demonstrations and excels in both text and regression tasks, demonstrating its generalizability across modalities.