Add dataset README with schema, corridors, and citation

README.md

@@ -1,3 +1,79 @@
----
-license: mit
----
+---
+license: cc-by-4.0
+task_categories:
+  - tabular-regression
+  - time-series-forecasting
+tags:
+  - finance
+  - remittance
+  - exchange-rates
+  - money-transfer
+  - crypto
+  - fiat
+  - open-data
+language:
+  - en
+pretty_name: Coinnect Remittance Rates
+size_categories:
+  - 10K<n<100K
+---
+
+# Coinnect Remittance Rates
+
+Daily snapshots of the cheapest money transfer routes across 22+ crypto exchanges and 19 remittance providers.
+
+## Description
+
+Every 3 minutes, Coinnect captures rate snapshots for key international money transfer corridors. This dataset contains the daily aggregated data — best route, cost percentage, recipient amount, and provider path for each corridor.
+
+## Data Format
+
+Each daily CSV file (`data/rates-YYYY-MM-DD.csv`) contains:
+
+| Column | Type | Description |
+|--------|------|-------------|
+| `captured_at_utc` | datetime | When the snapshot was captured |
+| `from_currency` | string | Source currency (e.g., USD, EUR, GBP) |
+| `to_currency` | string | Destination currency (e.g., MXN, NGN, PHP) |
+| `amount` | float | Amount in source currency |
+| `best_cost_pct` | float | Total cost as percentage (fees + spread) |
+| `best_time_min` | integer | Estimated transfer time in minutes |
+| `they_receive` | float | Amount recipient gets in destination currency |
+| `best_via` | string | Provider path (e.g., "Binance", "Wise", "Kraken+Yellow Card") |
+
+## Tracked Corridors
+
+USD→MXN, USD→BRL, USD→ARS, USD→NGN, USD→KES, USD→GHS, USD→PHP, USD→INR, USD→IDR, BTC→USD, BTC→MXN, BTC→NGN, ETH→USD, USDC→MXN, USDC→NGN, MXN→USD, BRL→USD, NGN→USD
+
+## Source
+
+Data is collected by [Coinnect](https://coinnect.bot) — a free, open-source money routing comparison tool.
+
+- **Website:** [coinnect.bot](https://coinnect.bot)
+- **GitHub:** [coinnect-dev/coinnect](https://github.com/coinnect-dev/coinnect)
+- **API:** `GET https://coinnect.bot/v1/snapshot/daily?date=YYYY-MM-DD`
+- **License:** CC-BY 4.0
+
+## Update Frequency
+
+Daily at 00:00 UTC. Each file contains ~20,000-30,000 rows (snapshots every 3 minutes × 18 corridors).
+
+## Use Cases
+
+- Track remittance cost trends over time
+- Compare crypto vs. fiat transfer routes
+- Train ML models for exchange rate prediction
+- Academic research on financial inclusion (SDG 10.c)
+- Validate provider fee claims
+
+## Citation
+
+```bibtex
+@dataset{coinnect_rates_2026,
+  title={Coinnect Remittance Rates},
+  author={Coinnect},
+  year={2026},
+  url={https://huggingface.co/datasets/coinnect-dev/coinnect-rates},
+  license={CC-BY-4.0}
+}
+```