Resolve an arbitrary freight identifier — one opaque string in, typed and cited candidates out. Use when you hold one identifier-ish token ("176", "UN1845", "NLRTM", "FOB", "22G1", "MSKU1100810", "D/E") and do not know what kind of identifier it is: each candidate names its entity type and carries the api_url and canonical_url of its full record.

Provide q: ONE identifier (single token, max 32 chars). Thirteen grammars all run — UN numbers, AWB prefixes, airline IATA/ICAO, airport IATA/ICAO, UN/LOCODE, ISO 6346 container numbers (check digit computed), HS codes (6-10 digits; national lines resolve at their 6-digit international parent), Incoterms, ADR tunnel codes, ULD serials, ISO container size/type codes. Ambiguity is the product: colliding grammars return MULTIPLE ranked candidates ("LHR" is Heathrow AND an Egyptian carrier's ICAO), never a silent guess.

Behavior: deterministic — normalize (trim, uppercase, collapse spaces/dashes, strip a UN prefix), match ALL grammars, rank by record-hit > verification status > static dataset prior (airlines/adr/unlocode first) > stable tiebreak; every candidate carries rank_basis so the ordering is inspectable. Zero candidates is a VALID result (count 0 + note), never an error. A failed container check digit returns a candidate with valid:false rather than dropping it. Rate-limited: a limit error carries reset_at, the UTC time the allowance resets.

Returns: query, normalized, count and candidates[] — each with entity_type, identifier_type, value_normalized, summary, record (the core fields the matching dataset holds), verification_status + verification_basis, rank_basis, canonical_url, api_url and a per-candidate dataset citation — under result, plus confidence, _source and citation (the FreightUtils v1 response envelope).

Limitations: v1 is SINGLE-TOKEN resolution, not free-text extraction — pass one identifier, not a manifest line; SCAC/BIC codes are not yet covered; a match asserts the identifier is known/well-formed, not that a shipment exists.

Related: every lookup tool this resolves into — adr_lookup, airline_lookup, airport_lookup, unlocode_lookup, hs_code_lookup, incoterms_lookup, container_lookup, uld_lookup, validate.