CLARITY: A Framework and Benchmark for Conversational Language Ambiguity and Unanswerability in Interactive NL2SQL Systems. - Tabinda Sarwar; Farhad Moghimifar; Cong Duy Vu Hoang; Xiaoxiao Ma; Shawn Chang Xu; Fahimeh Saleh; Poorya Zaremoodi; Avirup Sil; Katrin Kirchhoff (CoRR, 2026)