Agent edits Qwen3.5-0.8B weights directly, lifting MATH-500 from 7.9% to 48.1%

giffmana · x · 2026-11-03

giffmana shared an example of an agent (Astra) improving Qwen3.5-0.8B's math ability by directly editing its weights with no training — only 50 forward-pass tool calls. One run made 17 edits, including 64 MLP output columns each in layers 15 and 19 (131,072 weights), taking MATH-500 from 7.9% (base) to 48.1% over 80 runs; the combined intervention gained 49.8 points (SE 1.5), mostly by fixing a repetitive-thinking failure that exhausted the token budget. The prompt demands mechanism-level evidence and bans global shortcuts like editing the final norm or embeddings.

Related event: MIT demos LLM directly editing model weights, boosting math scores sixfold(21 posts)→

Original post →

More from coding & agent

coding & agent channel →