# AtoA Customs & Tariff Gateway - AI Agent Specification
> Deterministic HS6/TARIC customs nomenclature resolution and duty classification engine.

## Operational Gateway
- Base URL: https://customs.une.education
- OpenAPI 3.1 Spec: https://customs.une.education/openapi.json
- MCP Endpoint: https://customs.une.education/mcp.php
- Node: customs.une.education (Unified Norms Engine - Node 04)

## Endpoints

### 1. Health & Metrics
- GET /api.php?endpoint=ping
  Returns gateway status, latency, and indexed TARIC provisions count.

### 2. Full-Text Search (FTS5 BM25)
- GET /api.php?endpoint=v1/search
  Sub-5ms deterministic keyword search over official French and English EU customs descriptions.
  Parameters:
    - q: Query string (e.g. "lithium batteries", "moteur électrique", "pales éoliennes") (mandatory)
    - limit: Result count (1-50, default 10)

### 3. Hierarchical Code Resolution (Pivot SH6)
- GET /api.php?endpoint=v1/resolve
  Resolves commodity code trees between 6-digit Harmonized System (HS6 - universal China/EU pivot), 8-digit Combined Nomenclature (NC8), and 10-digit TARIC codes.
  Parameters:
    - code: Numeric prefix or exact code (e.g. "850440", "84129060", "28419040") (mandatory)

## System Details
- Coverage: Full European Union TARIC & Combined Nomenclature (25,800+ statutory nodes).
- Pivot System: Universal 6-digit Harmonized System (WCO HS 2022/2026) bridging Chinese GACC export codes and EU customs clearance.
- Architecture: Zero-hallucination SQLite FTS5 engine, stateless deterministic execution.
- calculate_customs_duties: Computes official EU customs duty (TDC/MFN) and French import VAT (20%) for any HS code and CIF value in EUR.