Add guide: Community Discovery Layer (x402 Service Discovery API)

guides/community-discovery-layer.md

@@ -0,0 +1,129 @@
+# Community Discovery Layer: x402 Service Discovery API
+
+> **Beyond the Bazaar — the community-built index of x402-payable services, with quality signals the official ecosystem page doesn't provide.**
+
+The **x402 Service Discovery API** is an open-source, community-maintained service registry for x402-enabled endpoints. While the [Bazaar](bazaar-discovery-layer.md) lists CDP-facilitator services, the Discovery API indexes **any** x402-compatible service — on any facilitator, any chain, with enriched quality data.
+
+**Live at:** `https://x402-discovery-api.onrender.com`
+
+---
+
+## Why This Exists
+
+The Bazaar answers "what services use x402?" The Discovery API answers "**which service should my agent actually pay?**"
+
+The difference matters when you have 251+ options:
+
+| Signal | Bazaar | Discovery API |
+|---|---|---|
+| Service listing | ✅ | ✅ |
+| Health check / uptime | ❌ | ✅ |
+| Latency scoring | ❌ | ✅ |
+| Facilitator compatibility | ❌ | ✅ |
+| ERC-8004 trust signals | ❌ | ✅ |
+| Category + capability tagging | ❌ | ✅ |
+| MCP tool integration | ❌ | ✅ |
+| Real-time auto-scanning | ❌ | ✅ (6hr refresh) |
+
+---
+
+## Quick Start (5 minutes)
+
+### Option 1: Use the MCP Server (Recommended for Claude/Cursor/Windsurf)
+
+```json
+{
+  "mcpServers": {
+    "x402-discovery": {
+      "command": "docker",
+      "args": ["run", "-i", "--rm", "ghcr.io/rplryan/x402-discovery-mcp:latest"]
+    }
+  }
+}
+```
+
+Then in your AI assistant:
+> "Find me x402 services for web scraping under $0.01 per call"
+
+### Option 2: HTTP API
+
+```bash
+# Find services by capability
+curl "https://x402-discovery-api.onrender.com/discover?query=data+analysis&max_price_usd=0.05"
+
+# Get full catalog
+curl "https://x402-discovery-api.onrender.com/.well-known/x402-discovery"
+
+# Check facilitator compatibility
+curl "https://x402-discovery-api.onrender.com/facilitator-check?service_id=your_service"
+```
+
+### Option 3: Python (via x402-payment-harness)
+
+```python
+from x402_harness import X402Client
+
+client = X402Client(private_key="your_eoa_key")
+# Discover + pay in one flow
+result = client.discover_and_pay(query="web scraping", max_price_usd=0.01)
+```
+
+---
+
+## MCP Tools Available
+
+The Discovery MCP server exposes 6 tools directly usable by Claude, Cursor, Windsurf, and any MCP-compatible AI assistant:
+
+| Tool | Description |
+|---|---|
+| `x402_discover` | Find services by capability, price, category |
+| `x402_health_check` | Real-time health status for any registered service |
+| `x402_list_categories` | Browse all service categories |
+| `x402_get_service` | Full details on a specific service |
+| `x402_facilitator_check` | Verify facilitator compatibility before paying |
+| `x402_register_service` | Add a new service to the catalog |
+
+---
+
+## Catalog Statistics
+
+- **251+ services** indexed (auto-scanned from x402.org/ecosystem + awesome-x402)
+- **6-hour refresh** cycle (auto-discovers new services)
+- **Multi-chain**: Base (primary), Ethereum, Solana
+- **Categories**: data, compute, agent, utility, AI/ML, DeFi, storage
+
+---
+
+## Registering Your Service
+
+Any x402-compatible service can be listed:
+
+```bash
+curl -X POST https://x402-discovery-api.onrender.com/register \
+  -H "Content-Type: application/json" \
+  -d '{
+    "name": "My x402 API",
+    "url": "https://api.example.com/v1/data",
+    "category": "data",
+    "price_usd": 0.005,
+    "network": "base-mainnet",
+    "description": "Real-time on-chain data feed"
+  }'
+```
+
+---
+
+## Related Tools
+
+- **[x402-payment-harness](https://github.com/rplryan/x402-payment-harness)** — EOA-based Python CLI for testing x402 payments without CDP. `pip install x402-payment-harness`
+- **[x402-routenet](https://x402-routenet.onrender.com)** — Smart routing across multiple x402 providers with automatic failover
+- **[MCP Registry](https://registry.modelcontextprotocol.io/servers/io.github.rplryan/x402-discovery-mcp)** — GitHub MCP Registry listing
+- **[Glama](https://glama.ai/mcp/servers/@rplryan/x402-discovery-mcp)** — Glama MCP listing (pending review)
+
+---
+
+## Source Code
+
+- Discovery API: https://github.com/rplryan/x402-discovery-mcp (API + MCP server)
+- Payment Harness: https://github.com/rplryan/x402-payment-harness
+- RouteNet: https://github.com/rplryan/x402-routenet