MLGym: A New Framework and Benchmark for Advancing AI Research Agents. - Deepak Nathani; Lovish Madaan; Nicholas Roberts; Nikolay Bashlykov; Ajay Menon; Vincent Moens; Amar Budhiraja; Despoina Magka; Vladislav Vorotilov; Gaurav Chaurasia; Dieuwke Hupkes; Ricardo Silveira Cabral; et al. (CoRR, 2025)