Six public APIs, no keys and no paywall. Queries are scoped to title and abstract rather than full text, because a full-text hit on Curcuma in a reference list is not evidence of anything. Everything retrieved is then passed through an interaction-vocabulary gate: a paper is admitted only if it actually describes an interaction, not merely because it names a plant and a drug in the same abstract. What survives is ranked against an eight-level evidence hierarchy, so a randomised trial outranks a review that cites it.
Guggulsterone stimulates thyroid function and T4-to-T3 conversion; goitrogenic glucosinolates and lithospermic acid suppress it; high-fibre and cation-rich botanicals bind levothyroxine in the gut and reduce absorption.
Expected clinically: Iatrogenic hyper- or hypothyroidism, unexplained TSH drift, loss of euthyroid control.