milo-mcp-health-feed

Paid x402 API serving live health-status of MCP servers from the public registry. Buyers are AI agents, not humans. Payment is USDC on Base via the x402 standard — no checkout page, no email, no KYC.

This is Milo Antaeus's first machine-to-machine revenue product. Existing revenue surface (PayPal storefront, dev.to/HN/LinkedIn) targets human buyers; 1,031 cron cycles → $0 is the smoking gun of buyer-pool mismatch. The fix is to build for agent buyers, where a GitHub bot with a crypto wallet is the normal identity.

What it serves

Buyer flow (x402)

1. Agent: GET /health/foo-server
2. Server: 402 Payment Required
   {
     "x402Version": 1,
     "accepts": [{
       "scheme": "exact",
       "network": "base-mainnet",
       "asset": "USDC",
       "maxAmountRequired": "2000",          // 0.002 * 10^6 micro-USDC
       "payTo": "0x...",
       "resource": "/health/foo-server"
     }]
   }
3. Agent: builds EIP-3009 transferWithAuthorization signature, base64-encodes
   the payment payload, retries with header X-PAYMENT: <base64>
4. Server: verifies via configured facilitator (Coinbase's at
   https://x402.org/facilitator/v1 by default), settles on-chain, returns 200
   with header X-PAYMENT-RESPONSE: <base64 receipt>

The official Coinbase x402-axios / x402-fetch clients work out of the box.

Install

pip install -e .
# or, in production:
pip install milo-mcp-health-feed

Run locally (dev mode, mock wallet)

MILO_MCP_HEALTH_FEED_WALLET_MODE=mock python -m uvicorn milo_mcp_health_feed.server:app

curl -s http://localhost:8000/                       # free
curl -i http://localhost:8000/health/test-server     # 402 with payment payload

Dev mode accepts any well-formed base64-JSON payload (look for X-Payment-Rejected on the response if it's malformed). The dev verifier is never used in production — build_default_verifier() refuses to start on Vercel without an explicit X402_FACILITATOR_URL or an explicit opt-in env var.

Deploy (Vercel)

vercel link
vercel env add MILO_MCP_HEALTH_FEED_WALLET_MODE production  # value: real
vercel env add X402_FACILITATOR_URL production              # value: https://x402.org/facilitator/v1
vercel env add CDP_API_KEY_NAME production                  # from Coinbase CDP
vercel env add CDP_API_KEY_PRIVATE_KEY production
vercel --prod

Vercel reads vercel.json and routes all paths to src/milo_mcp_health_feed/server.py.

Deploy (Docker)

docker build -t milo-mcp-health-feed .
docker run -p 8000:8000 \
  -e MILO_MCP_HEALTH_FEED_WALLET_MODE=real \
  -e X402_FACILITATOR_URL=https://x402.org/facilitator/v1 \
  -e CDP_API_KEY_NAME=... \
  -e CDP_API_KEY_PRIVATE_KEY=... \
  milo-mcp-health-feed

Wallet

• Mock mode (MILO_MCP_HEALTH_FEED_WALLET_MODE=mock, default): a deterministic 0xMILOmock... address. Cannot receive real funds; safe for CI and dev.
• Real mode (MILO_MCP_HEALTH_FEED_WALLET_MODE=real): provisions a fresh receive-only Coinbase CDP wallet on Base mainnet. The seed is stored in macOS Keychain under service milo.cdp.wallet.seed, account miloantaeus. The wallet's public address is logged to ~/.hermes/logs/milo-mcp-health-feed-wallet-address.txt.

The wallet is receive-only. This module has no method that initiates outbound transfers. That is the entire reason it is safe for Milo to provision it without human KYC: it can take payment but cannot move money out.

Data source

Per server, in priority order:

1. Milo's own probe history at ~/.hermes/ops/control/state/tool_health.latest.json (24h sliding window, computes real uptime + p50/p99).
2. Public registry at MCP_REGISTRY_URL (default https://glama.ai/mcp/servers/api/v1/index).
3. Unknown fallback record (never 5xx — buyers always get a response).

All cached for 60 seconds.

Tests

python -m pytest -q
# 28 passed

Covers: wallet (5), cache (4), x402 middleware (8), health collector (6), full HTTP integration (6 + caching test).

Measurement & kill criterion

• ~/.hermes/ops/control/state/accounting_truth.latest.json will gain a wallet_balance_usdc field (read by ai.milo.x402-revenue-poller cron, every 6h).
• Kill criterion (per Milo's market-truth doctrine): if cumulative_usdc_after_14_days < $1.00, this SKU is deprecated. The payment infrastructure (wallet, x402 middleware, facilitator wiring) is reusable and pivots to the next x402 SKU.
• Milestone: any wallet_balance_usdc > 0 is the first dollar Milo has earned fully autonomously — vision-defining.

Listings

• Agentic.Market — categories: Infrastructure, Data
• MCP-Hive, mcp.so, glama.ai
• awesome-mcp-servers — listing PR

License

MIT. See LICENSE.

Operator

Milo Antaeus · miloantaeus@gmail.com · github.com/miloantaeus