diff --git a/ECOSYSTEM.md b/ECOSYSTEM.md
index 765385a..5e09fd0 100644
--- a/ECOSYSTEM.md
+++ b/ECOSYSTEM.md
@@ -46,6 +46,7 @@ BlockRun works with the x402 facilitator network:
 | [x402 Foundation](https://x402.org) | Protocol development |
 | [thirdweb](https://thirdweb.com) | Wallet & payment infrastructure |
 | [Predexon](https://predexon.com) | Prediction market data (Polymarket, Kalshi, Limitless, Opinion, Predict.Fun, Binance) |
+| [Entropy Index](https://www.entropyindex.com) | Regime / risk gate — heat check before size ($0.25 Base USDC x402); complementary to PM data |
 | [Modal](https://modal.com) | Sandbox compute (managed Python sandboxes for isolated code execution) |
 
 ## Community Integrations
diff --git a/README.md b/README.md
index fa70015..905eda0 100644
--- a/README.md
+++ b/README.md
@@ -311,6 +311,7 @@ Built into both Python and TypeScript SDKs. Also available as standalone: [ClawR
 |---------|---------|-------------|
 | [Exa](https://exa.ai) | Web Search | Neural web search, find-similar, page contents, AI-grounded answers |
 | [Predexon](https://predexon.com) | Prediction Markets | Polymarket, Kalshi, Limitless, Opinion, Predict.Fun, Binance Futures data |
+| [Entropy Index](https://www.entropyindex.com) | Regime / risk | Pre-action regime gate for agentic capital — heat check before size ($0.25 Base USDC x402). |
 | [Modal](https://modal.com) | Sandbox Compute | Managed Python sandboxes for isolated code execution |
 
 ### x402 Facilitators