Flow-Direct: Feedback-Efficient and Reusable Guidance for Flow Models via Non-Parametric Guidance Field

In three linesFlow-Direct introduces a training-free guidance framework for flow models using a persistent non-parametric guidance field. Analytically derived from the log-density ratio between base and reward-weighted target distributions, this field accumulates all evaluated samples to improve feedback efficiency and enable reusability without additional reward evaluations.

Summary generated by Claude — human-verified