Search the NPPES NPI registry for individual practitioners and healthcare organizations by name, organization name, location, provider type, and specialty. Plain-language specialty terms (e.g. "cardiologist", "pediatric cardiologist") resolve through the bundled NUCC taxonomy; the top match's specialization or classification becomes taxonomy_description, and all resolved candidates are returned in metadata. Location belongs in the dedicated city/state/postal_code inputs, not inside specialty. Each provider row includes the NPI, name, primary specialty, city/state/ZIP, type, and active/deactivated status; the NPI is the input for npi_get_provider when the full record is needed. At least one search criterion is required, and the registry rejects state-only searches. When city/state/postal_code are given, only practice addresses are searched, never mailing addresses: a provider is returned only when its primary practice location or one of its other practice locations matches all of them. A provider kept on another practice location names it in matchedLocation. Name searches also match former and other names, sorted by current name; such a row names the matching name in matchedOtherName. The registry never reports a true match total, and one search reaches only its first 1200 matches: a full page names the next in nextPage, and the terminal window (skip 1000, limit 200) returns continuationPostalCodes, postal_code prefixes that continue the search.
Fetch NPPES records from up to 100 raw NPI entries per call. Deduplicate in input order, validate check digits, and look up the first 10 distinct valid NPIs; remaining valid NPIs are listed in unprocessed and are never looked up. Decodes an NPI from a claim, prescription, or another health data source into the provider's professional-practice profile: every taxonomy with its primary flag, license number and state; practice addresses with phone and fax (only LOCATION rows are kept for individual providers, so their mailing address is withheld; organizations also carry their mailing address); credential, sex, sole-proprietor flag; enumeration and last-updated dates; active/deactivated status; secondary identifiers (Medicaid, etc.); and FHIR/Direct endpoints. Each NPI must be 10 digits with a valid check digit (its last digit); every NPI failing the check digit lands in invalid and is never looked up. Reports partial success: valid NPIs with no registry record (deactivated or never enumerated) land in notFound, while NPIs whose lookup hit an upstream error (registry unavailable, timeout) land in errored — kept distinct from confirmed misses — rather than failing the whole call.
Resolve and browse the NUCC Healthcare Provider Taxonomy — the specialty code set NPPES uses — fully offline (bundled). Mode `resolve` turns a plain-language specialty (e.g. "cardiologist", "heart doctor") into matching active taxonomy entries, excluding codes NUCC marks inactive; mode `get` returns the full entry for an exact code, including NUCC's Notes; mode `browse` walks the hierarchy (grouping → classification → specialization), optionally filtered by grouping and NUCC section. Individual includes Group codes; section does not determine NPI entity type, which comes from NPPES enumeration_type. Every entry carries its status, and an inactive code names its replacement when NUCC gives one; `get` and `browse` still return inactive codes. A resolved entry's specialization, or its classification when specialization is absent, maps directly to npi_search_providers.taxonomy_description.