# SKALOS

As skill libraries grow, semantically similar skills become hard to tell apart from descriptions alone. SKALOS builds a multi-hierarchy capability graph of capability, method, artifact and constraint nodes, uses Max–Min witness learning to require that one implementation jointly covers every query requirement, and calibrates extraction errors with ranking feedback. On SkillRet its NDCG@10 is 2.68 points above a matched text-only reranker; on controlled ALFWorld tasks, witness-guided skill selection raises success from 22% to 29%.

As skill libraries grow, semantically similar skills become hard to tell apart from descriptions alone. SKALOS builds a multi-hierarchy capability graph of capability, method, artifact and constraint nodes, uses Max–Min witness learning to require that one implementation jointly covers every query requirement, and calibrates extraction errors with ranking feedback. On SkillRet its NDCG@10 is 2.68 points above a matched text-only reranker; on controlled ALFWorld tasks, witness-guided skill selection raises success from 22% to 29%.