MIRA-AC trains research agents on proxy feedback, lifting symbolic regression from 50 to 63 solved

anirudhg9119 · x · 2026-10-14

The author presents MIRA-AC: an autoresearch policy trained purely on proxy feedback that improves gold outcomes over untrained MIRA:

Key design: the critic sees causal data; the actor does not. For RL, full research episodes are reconstructed and decision-level advantages computed from downstream outcomes; only the meta-reasoner's reasoning and work orders are updated while executor, tools and context curation stay fixed — "training WHAT, not HOW." To fix credit-assignment bias from auto-compaction splitting long episodes, MIRA resets context at every decision and stitches meta-reasoning decisions back into one logical episode.

Related event: MIRA-AC: Training Autoresearch Agents with Proxy Feedback and Credit Assignment(14 posts)→

Original post →

More from coding & agent

coding & agent channel →