Publish x402 Price Index free tier

Daily index, stratified probe sample, dataset card and schema.

README.md

@@ -74,8 +74,32 @@ Only structured facts are distributed here.
 
 ## Full dataset
 
-The complete corpus, daily refresh, and historical series are available commercially.
-Contact: https://animica.org — or open a discussion on this repo.
+The complete corpus — every probe row plus `resource`, `price_atomic`, `pay_to`, the raw
+`accepts_json` and the prober's `error` diagnosis — is available as a monthly subscription.
+
+**$29/month** · [Subscribe with PayPal](https://www.paypal.com/webapps/billing/plans/subscribe?plan_id=P-4VT44042YX381234RNKPE5XI)
+
+After subscribing, PayPal shows a subscription id beginning `I-`. Exchange it for a
+download token:
+
+```bash
+curl -X POST https://animica.dev/api/mkt/v1/data/x402-index/activate \
+  -H 'content-type: application/json' \
+  -d '{"subscriptionId":"I-YOUR-SUBSCRIPTION-ID"}'
+```
+
+The response carries direct URLs for both formats:
+
+```bash
+curl -o x402-price-index.csv \
+  "https://animica.dev/api/mkt/v1/data/x402-index/download?file=csv&token=YOUR_TOKEN"
+```
+
+`file=csv` (~23MB) or `file=jsonl` (~28MB). Tokens last 30 days and can be reminted at any
+time; entitlement is re-checked against PayPal on every download, so cancelling stops
+access immediately. Files are rebuilt as the census grows — re-download for the latest.
+
+Questions: open a discussion on this repo.
 
 ## Citation
 

data/sample/stats.json

@@ -1,5 +1,5 @@
 {
-  "generated_at_utc": "2026-09-07T05:07:58+00:00",
+  "generated_at_utc": "2026-09-07T05:56:12+00:00",
   "probe_rows": 26366,
   "distinct_hosts": 2509,
   "distinct_endpoints": 26366,