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ScientistTwo: Pioneering the Human Knowledge Frontier with Autonomous AI

Automate the end-to-end research loop from problem definition through experiments, ablations, review and rebuttal.

Jaehyun Nam, Jinsung Yoon, Yanzhou Pan, Yubo Wang, Rui Meng, Parthasarathy Ranganathan, Tomas PfisterSep 17, 2026arXiv preprint14 min read
AI Agentsautonomous researchmulti-agent systemsAI scientistevaluationpeer reviewscientific discoveryclosed-loop researchidea evolutionsubset-to-full evaluation

TL;DR

ScientistTwo reports 86 successful advances across 107 problems and a 25.2% average relative gain over human SOTA baselines.

Why It Matters

It treats autonomous research as a stateful workflow with explicit evidence and review gates.

Research Brief

The shortest useful explanation.

ScientistTwo reports 86 successful advances across 107 problems and a 25.2% average relative gain over human SOTA baselines.

closed-loop researchidea evolutionsubset-to-full evaluationablationpeer reviewrebuttalautonomous researchmulti-agent systems

Core Explanation

A fully autonomous multi-agent research framework that generates ideas, runs experiments, performs ablations, drafts papers, conducts peer review and rebuttal experiments, and meta-reviews the result.

Why It Matters

It treats autonomous research as a stateful workflow with explicit evidence and review gates.

ScientistTwo multi-agent research pipeline.

ScientistTwo overview

Original paper architecture figure.

Section 01

The Problem

01 THE PROBLEM

Expert-level autonomous research needs multi-dimensional evaluation, ablation-driven analysis and active response to peer review, not only single-metric optimization.

1Single-metric limits2Evidence loops3Review

Section 02

The Big Idea

02 THE BIG IDEA

ScientistTwo makes the full research lifecycle an explicit multi-agent loop: limitation extraction, idea generation, subset testing, full experiments, ablations, drafting, peer review, rebuttal experiments and meta-review.

1Closed loop2Verification gates

Section 03

How It Works

03 HOW IT WORKS

Ideas are screened on benchmark subsets before full experiments; promising ideas are refined, ablated, drafted, reviewed and rebutted with new experiments before finalization.

1Limitations2Ideas3Subset tests4Full tests5Ablations6Review/rebuttal7Meta-review

Section 04

The Math

04 THE MATH

The system maps a scientific problem to a paper and reproducible codebase through specialized agents; review scores use a 1–10 scale and acceptance thresholds.

1Problem-to-artifact2Review score

Section 05

Architecture

05 ARCHITECTURE

Idea Generator, Evaluator, Analyzer, Writer, Peer-Review and Meta-Review groups coordinate specialized critics and refiners.

1Idea Generator2Evaluator3Analyzer4Writer5Peer-Review6Meta-Review

Section 06

Experiments

06 EXPERIMENTS

On 107 problems, ScientistTwo reports 86 successful advances and 25.2% average relative gain. ScientistOne: 21 papers, ScholarPeer 3.8±1.2/14.3%, Stanford 4.1±0.7/0%. ScientistTwo: 86 papers, ScholarPeer 7.5±1.3/91.9%, Stanford 5.7±0.6/72.1%. Venue generated results: ICLR 4/5 with 7.0±1.2/100.0% and 5.4±0.2/75.0%; NeurIPS 33/38 with 7.3±1.7/87.9% and 5.6±0.7/75.8%; ICML Spotlight 49/64 with 7.6±1.0/93.9% and 5.7±0.6/69.4%; overall 86/107 with 7.5±1.3/91.9% and 5.7±0.6/72.1%.

1107 problems286/107380.4% success425.2% gain

Section 07

What We Learned

07 WHAT WE LEARNED

Peer-review ablation reports ScholarPeer acceptance 46.9% without rebuttal, 79.6% after one round and 93.9% after two; Stanford acceptance 49.0%, 73.5% and 69.4%. The production lesson is to make review trigger evidence gathering rather than only text edits.

1Ablation2Review-driven evidence3Held-out evaluation

Section 08

What Came Next

08 WHAT CAME NEXT

Related work includes ReAct, AutoGen, SWE-agent, OpenHands, AIDE, MLE-STAR, AI Scientist, AI Scientist-v2, PaperOrchestra and ScholarPeer. Future work is broader autonomous discovery with stronger verification and reproducibility.

1AI Scientist2AI Scientist-v23ScientistOne4ScholarPeer

Section 09

Engineering Takeaways

ENGINEERING TAKEAWAYS

Use durable workflow state, executable experiments, subset-first screening, first-class ablations, tool-using review agents and a held-out evaluator. Failure modes include evaluator leakage, reviewer correlation, runaway compute and polished prose before validity.

1Workflow state2Held-out evaluator3Compute budgets4Artifact lineage

Formulas

Problem-to-artifact mapping

(mathcalP+,mathcalC+)=mathcalA(mathcalG),quadmathcalA=mathcalA1,dots,mathcalANa(\\mathcal{P}^{+},\\mathcal{C}^{+})=\\mathcal{A}(\\mathcal{G}),\\quad \\mathcal{A}=\\{\\mathcal{A}_1,\\dots,\\mathcal{A}_{N_a}\\}

A scientific problem is transformed into a paper and reproducible codebase by specialized agents.

Aautonomous research system
Gproblem
Aispecialized agent
C+codebase
P+paper

Related Research

References