Co-Scientist (Google)

Gemini-based multi-agent reasoning engine focused on hypothesis generation, using a generation/reflection/ranking/evolution ensemble with Elo-style tournaments. Validated in three peer-reviewed biomedical case studies.

   
Affiliation Google Cloud AI Research / Google DeepMind / Google Research, with collaborators at Stanford, Imperial College London, and Houston Methodist (Google Research)
First introduced 2025-02 (initial blog announcement); peer-reviewed paper accepted 2026-05
Lifecycle stages Hypothesis, Experiment design
Autonomy level Semi-autonomous (scientist-in-the-loop collaborative paradigm)
Domain focus General; validated in biomedicine (drug repurposing, target discovery, antimicrobial resistance)
Availability Closed / API only — full source not public; experimental access program announced; Gemini foundation model accessible via Google APIs

Approach

Multi-agent system built on Gemini, comprising specialized agents (Generation, Reflection, Ranking, Evolution, Proximity, Meta-review) coordinated via an asynchronous task framework. Uses self-play scientific debate for hypothesis generation, an Elo-style tournament to compare hypotheses, and an evolution loop to refine them by scaling test-time compute.

Validation

Three biomedical case studies:

  • Drug repurposing for acute myeloid leukemia (AML) with in vitro confirmation.
  • Novel epigenetic targets for liver fibrosis confirmed in human hepatic organoids.
  • Recapitulation of a then-unpublished bacterial gene-transfer mechanism in antimicrobial resistance, discovered independently by collaborators at Imperial College.

Notable results

Identified novel single-agent and combination repurposing candidates for AML showing selective cytotoxicity at clinically relevant concentrations. Ranked epigenetic targets with anti-fibrotic activity in organoids. Independently recapitulated an unpublished AMR gene-transfer mechanism.

Primary paper

Gottweis et al., “Accelerating scientific discovery with Co-Scientist,” Nature 2026.

Other references

Code

Not released. Pseudocode and system prompts provided in supplementary notes.