The callable STATE EXPERT — the data-availability + regulation X-ray for a US state. Given a 2-letter state code (e.g. 'CT'), returns: (1) DATA AVAILABILITY — how many hospitals are priced, total price rows, distinct billing codes, care sites mapped, and payers with resolved coverage; (2) the REGULATION object — the rules of the game in that state (transparency regime, required disclosures, public datasets like an APCD or rate-setting authority, and the completeness bar); and (3) the computed GAPS — required-or-known datasets we have NOT yet ingested (e.g. a mandatory APCD), so absence is reported as gap-vs-expected, not silently. This is the 'what data do we have in this state, what is required here, and what is missing' entry a higher-level agent or operator reasons over. Because hospital pricing is a NATIONAL substrate, a state can show many hospitals priced even before its county map is built (e.g. MD). Stateless + state-parameterized: one runtime serves every state. To price a code across the state's hospitals, call compare_hospital_rates. SOURCE: curated hospital chargemaster + care-site registry + the state-regulation object.