# DataNexusAI

> DataNexusAI is a public data API for Bulgarian SEBRA payments, PTP road
> accidents, Hearthstone card data, EU agri-food prices, and trade/market
> analytics. Paid endpoints use x402 USDC micropayments. Docs are free.

Base URL: https://api.datanexusai.org
Human docs: https://api.datanexusai.org/docs
Legacy docs: https://api.datanexusai.org/api/
OpenAPI: https://api.datanexusai.org/openapi.json
x402 discovery: https://api.datanexusai.org/.well-known/x402
This file: https://api.datanexusai.org/llms.txt

## API categories

- SEBRA: Bulgarian SEBRA public payment analytics (egovbg_sebra_days).
  Docs: https://api.datanexusai.org/docs/sebra/
- PTP (road accidents): Bulgarian MoI road accident reports and deadly location clusters.
  Docs: https://api.datanexusai.org/docs/ptp/
- Hearthstone: Structured Hearthstone card data (EN/BG).
  Docs: https://api.datanexusai.org/docs/hearthstone/
- Agri-food: EU agri-food price datasets (cereals, oilseeds, pigmeat).
  Docs: https://api.datanexusai.org/docs/agrifood/
- Trade and markets: Eurostat Comext trade and agricultural market insights.
  Docs: https://api.datanexusai.org/docs/trade/
- Macro & rates (derived): Derived EU macro, ECB monetary stance, yield-curve slopes, EURUSD analytics, and selected FRED-backed derived indicators. Raw FRED series are not exposed as DataNexusAI endpoints.
  Docs: https://api.datanexusai.org/docs/macro/

## Main paid endpoints (examples)

- Hearthstone card lookup: GET /api/hearthstone/getCard?name=Fireball
- SEBRA payment periods: GET /api/sebra/getPeriodsWithMostPayments?period=days&from=01-10-2020&to=01-11-2020
- PTP crashes by city: GET /api/ptp/getPtpPerCity?city=Sofia&year=2025
- Agri-food datasets: GET /api/v1/datasets?limit=100
- Comext trade rows: GET /api/v1/trade?reporter=BG&product=1001&date_from=2020
- Market snapshot: GET /api/v1/markets/BG/1001

## x402 payments

- Protocol: x402 V2 (exact scheme, USDC)
- Price: $0.01 USD per paid request
- Networks: Base, Polygon, Arbitrum One
- Asset: USDC
- Unpaid call → HTTP 402 + PAYMENT-REQUIRED header
- Client signs payment → retry with PAYMENT-SIGNATURE header
- Success → 200 JSON + PAYMENT-RESPONSE header
- Spec: https://docs.x402.org
- Free: /docs, /openapi.json, /llms.txt, /.well-known/x402, /api/, /api/docs*

## Example calls

curl -i "https://api.datanexusai.org/openapi.json"
curl -i "https://api.datanexusai.org/llms.txt"
curl -i "https://api.datanexusai.org/.well-known/x402"
curl -i "https://api.datanexusai.org/api/hearthstone/getCard?name=Fireball"
# ↑ unpaid non-allowlisted client receives 402 (x402 challenge)

## Notes for agents

- Prefer OpenAPI for full parameter/response schemas.
- Runtime 402 PAYMENT-REQUIRED is authoritative over static docs.
- Do not invent alternate payment protocols; use x402 only.