TLDR: we built Oh My Quant, a harness designed for research from first principles -> fast & cheap experiment running, monitoring and storing. Our harness with Opus is top 1 on MLE leaderboard.

The point is to let an agent spawn, run, and track a lot of hypotheses and experiments in parallel without confusing itself.

Most harnesses right now are for coding, which is fine for SWE but not ideal for research. Good research means shipping many hypotheses, experiments, and validations, instead of static PRs. We used Codex and Claude Code for a while, but they have poor research 'taste' and are bad at running and comparing multiple experiments.

We ended up designing Oh My Quant from scratch for our own research. The harness is built around hypothesis → experiment → evidence, with a few simple principles: no hardcoded workflows, main agent decides which subagents to spawn; cheap and fast experiment design and tracking; harness handles all tedious things like parsing experiment metadata, run and monitor experiment, store result metrics - and leaves the agent's entire context window free to do the intelligent judgement calls for research design.