FRONT DOOR CHECK — if the question spans more than one capability ("find 200MW near Dallas with fiber, then rank the markets"), call execute_plan(intent="<the user's question, unchanged>"). find_sites is the right single call when the user has NO site yet and wants candidates to start from — the first step of data center site selection. THE INVERSE QUERY: every other DC Hub siting tool needs a coordinate you already have — analyze_site scores one, get_composite_site_score grades one, rank_sites orders candidates YOU already enriched, find_alternatives needs a seed facility. This one answers "where should I even be looking?". Returns candidate SEARCH AREAS anchored on real HIFLD substations at or above min_voltage_kv, spatially de-duplicated by cluster_km so a dense metro yields distinct areas instead of 40 near-identical rows, each carrying measured distance to the nearest gas pipeline and fiber route plus state-grain moratorium context, and a next_calls handoff. ★ WHAT A CANDIDATE IS NOT: a search area is NOT a parcel, NOT a listing, and NOT land known to be for sale — DC Hub holds no land-ownership or availability data, and hosted parcel boundaries cover ONE county (Loudoun VA), so analyze_parcel will 404 on most of these points BY DESIGN. Read each as "start looking here", then score the coordinate with analyze_site. ★ READ constraint_coverage BEFORE CALLING THIS A SCREENED LIST: a constraint filters ONLY when its layer actually answered. If a layer errors, the set comes back UNFILTERED with applied:false plus a reason and an instead, the names repeated in top-level unapplied_constraints and an unapplied_constraints_warning — an unevaluable constraint is never a passed constraint. fiber_distance_km is a straight-line CHORD between a route's endpoints, NOT the true polyline path; its basis is stamped on every candidate and get_fiber_readiness at the coordinate is the engineered read. hazard/moratorium are STATE grain, never a site verdict. A geography is REQUIRED — pass state, or lat+lon (+radius_km); without one you get a legible 400 (error_code geography_required), never a nationwide scan. Free tier coarsens coordinates to ~11 km and withholds operator/capacity. Answers "where should I even be looking for 200 MW in Ohio" and "which areas near Dallas sit on 230kV with gas within 5 miles". Try: find_sites state=OH min_voltage_kv=230 max_gas_km=8 — or find_sites lat=39.04 lon=-77.48 radius_km=60 min_voltage_kv=500. Do NOT use to score a site you already have (analyze_site), to rank candidates you already enriched (rank_sites), to find similar FACILITIES to a known one (find_alternatives), or for interconnection-queue survivors (get_refined_queue).
