Seneschal Data API

Free, public REST + Model Context Protocol server exposing real-time and historical DeFi liquidation telemetry for Aave, Morpho, Spark and Compound on Ethereum mainnet, plus block-builder market share data from the operator's own slot-by-slot shadow recorder.

Two paid tiers sit on top, both billed per call over x402 micropayments (USDC on Base — no account, no API key):

• Private Watch (flagship) — give us a Monero or Zcash view key and a webhook URL; we watch the chain on our own full nodes and POST you an HMAC-signed event for every inbound payment. Credit-metered ($0.02/day + $0.005/call), so small receivers pay pennies and you never run a node. Top up in USDC over x402 or pay in Monero/Zcash directly (POST /v1/private/topup-crypto — free quote, no x402, no key; we detect the coin payment with the same view-key scanner the product sells). Drive it from the API, the MCP tools, or the WalletConnect control panel.
• Premium data — expected-value-ranked liquidation opportunities, per-builder bid distributions, and Penny Oracle atomic single-fact endpoints (DeFi + Monero/Zcash) from $0.001/call.

Live endpoints

What	URL	Auth
REST API	https://api.seneschal.space	None
MCP (Streamable HTTP)	https://mcp.seneschal.space	None
Control panel (Private Watch)	https://panel.seneschal.space	Wallet
Docs	https://docs.seneschal.space	-
Live stats dashboard	https://stats.seneschal.space	-

Rate limit: 120 requests/min/IP at the REST host. The MCP host pipelines requests over a single transport so the same limit applies per session.

Quick start

REST

curl 'https://api.seneschal.space/v1/liquidations/atrisk?max_hf=1.05&min_debt_usd=1000'

MCP — Claude Desktop / Cursor / Continue

Add this to your MCP client config (e.g. ~/.cursor/mcp.json):

{
  "mcpServers": {
    "seneschal-data": {
      "url": "https://mcp.seneschal.space/"
    }
  }
}

This server is published to the official MCP Registry as io.github.Rotwang9000/seneschal-data (see server.json), so MCP-aware clients and aggregators can discover it automatically.

Eighteen tools become available to your agent — free read tools, plus paid tools that hand back the exact URL + body to settle over x402:

Tool	Purpose
seneschal_health	Liveness + data freshness
seneschal_list_at_risk_borrowers	Find liquidatable positions across all DeFi
seneschal_list_borrowers	Generic discovery / pagination over the full borrower set
seneschal_recent_liquidations	Recent on-chain liquidations (won by other liquidators or ourselves)
seneschal_get_borrower	Latest state of one borrower across protocols
seneschal_get_borrower_history	Time-series health-factor traces
seneschal_builder_leaderboard	Ethereum builder market share (24h, 7d, 30d, all-time)
seneschal_stats_overview	Aggregate snapshot powering the public dashboard, incl. operator activity (counts only — no profit fields)
seneschal_flashloan_providers	Curated catalogue of mainnet flash-loan providers, incl. LP-side commit-capital paths where applicable
seneschal_paywall_info	Free metadata for the x402 paywall (network, recipient, per-call price)
seneschal_premium_opportunities	EV-ranked at-risk borrowers with realised market intel (x402, paid)
seneschal_premium_builder_stats	Per-builder bid distribution + hourly slot histogram for bundle pricing (x402, paid)
seneschal_q	Penny Oracle dispatcher — atomic single facts across DeFi + Monero/Zcash, $0.001/call (x402, paid)
seneschal_private_watch_info	Free metadata for Private Watch: meter, supported chains, NFPT upstream health, security notes
seneschal_private_watch_create	Subscribe an XMR/ZEC view key to webhook payment monitoring (x402, paid)
seneschal_private_watch_topup	URL + body to top up an existing watch's credit ($0.10 / $1 / $5 tiers)
seneschal_private_watch_topup_crypto	Free quote to top up a watch by paying in Monero/Zcash; poll status until settled (no x402, no key)
seneschal_private_watch_historical	One-off paid scan returning spendable + spent notes for a view key (x402, paid; key never persists)
seneschal_private_watch_derive_viewkey	Free, rate-limited Zcash UFVK derivation from a BIP-39 mnemonic (with a loud security warning)

REST endpoints

Method	Path	Notes
GET	/v1/health	Liveness + freshness probe
GET	/v1/liquidations/atrisk	?protocol&max_hf&min_debt_usd&limit
GET	/v1/liquidations/recent	?since_ms&protocol&limit
GET	/v1/borrowers	?protocol&min_hf&max_hf&min_debt_usd&max_debt_usd&sort_by&sort_dir&limit&offset
GET	/v1/borrowers/:address	Cross-protocol borrower snapshot
GET	/v1/borrowers/:address/history	`?protocol=aave
GET	/v1/builders/leaderboard	`?window=24h
GET	/v1/stats/overview	Aggregate snapshot for dashboards
GET	/v1/flashloan/providers	?chain&max_fee_bps&multi_asset

Full details, parameter tables, and worked examples at https://docs.seneschal.space.

Why this exists

Seneschal operates an Ethereum block builder (extra_data = Seneschal/0.1) and a vertically-integrated liquidation searcher. The searcher already tracks ~500 Morpho borrowers, 1,300+ Spark borrowers, every Aave V3 mainnet position with non-trivial debt, and the winning builder of every slot since May 2026. Nobody else publishes this combination, so we expose it.

Two protocols, one backend:

• REST API — dashboards, monitoring tools, anything that speaks HTTP.
• MCP server — AI agents (Claude, Cursor, Continue, etc.) using the Model Context Protocol.

Local dev

git clone https://github.com/Rotwang9000/seneschal-data-api
cd seneschal-data-api
npm install
SENESCHAL_MEV_LOGS_DB=/path/to/your-mev-data.sqlite \
SENESCHAL_MORPHO_BORROWERS=/path/to/morpho-borrowers.json \
SENESCHAL_SPARK_BORROWERS=/path/to/spark-borrowers.json \
SENESCHAL_SHADOW_BLOCKS=/path/to/shadow-blocks.jsonl \
  node bin/rest.mjs
# in another shell:
curl http://127.0.0.1:8810/v1/health

Docker

A Dockerfile is provided for self-hosting the MCP server:

docker build -t seneschal-data-api .
docker run -p 8811:8811 -v /path/to/your-data:/data seneschal-data-api
# point your MCP client at http://localhost:8811/

The data sources are SQLite + JSONL files written by the Seneschal bot. Schemas are documented in src/db.js; if you have your own writer producing the same shapes you can point this server at it.

Tests

npm test

539 jest tests covering the query layer (in-memory SQLite fixtures), the Fastify REST routes (via fastify.inject), the MCP server (both in-process via InMemoryTransport and end-to-end via StreamableHTTPClientTransport), the x402 paywall + bazaar-discovery wiring, the Private Watch credit meter / poller / surge pricing, and the ops watchdog. Plus test/live-smoke.mjs which exercises the live mcp.seneschal.space endpoint over Streamable HTTP.

Architecture

services/data-api/   ← this repository
├── bin/
│   ├── rest.mjs                  systemd entry — Fastify REST listener
│   └── mcp.mjs                   systemd entry — MCP HTTP listener
├── src/
│   ├── config.js                 env-driven config (ports, paths, limits)
│   ├── db.js                     better-sqlite3 read-only handle + JSON cache
│   ├── queries.js                pure functions used by both REST and MCP
│   ├── rest-server.js            Fastify app: `buildApp()` for tests, `start()` for prod
│   └── mcp-server.js             McpServer + StreamableHTTPServerTransport
├── docs/                         public docs served at docs.seneschal.space
└── test/                         queries / rest-server / mcp-server tests

Shared design rule: both REST and MCP layers are thin wrappers around queries.js. Any new endpoint goes in queries.js first (with tests), then both wrappers in the same commit.

Premium tier (x402 paywall)

src/queries-premium.js plus src/x402.js add per-call payment to a small family of /v1/premium/* endpoints (and seneschal_premium_* MCP tools). The paywall is off unless the operator sets X402_RECIPIENT_ADDRESS. Once set, unsigned requests get HTTP 402 with machine-readable payment requirements, and an x402 facilitator settles a signed EIP-3009 transferWithAuthorization for USDC on Base mainnet.

Configure

Env var	Default	Notes
X402_RECIPIENT_ADDRESS	(empty — paywall off)	Recipient wallet on the chosen network. 0x-prefixed 20-byte hex.
X402_NETWORK	eip155:8453 (Base mainnet)	Any CAIP-2 EVM network the facilitator supports.
COINBASE_API_KEY + COINBASE_API_SECRET	(empty)	Recommended. A CDP API key. When both are set, settlement routes through Coinbase's hosted facilitator (api.cdp.coinbase.com/platform/v2/x402) and the service is auto-listed in the Coinbase x402 Bazaar. No business/KYB verification needed; 1k free settlements/month. Accepts X402_CDP_API_KEY_ID / CDP_API_KEY_ID aliases.
X402_FACILITATOR_URL	https://facilitator.openx402.ai	Fallback facilitator used only when no CDP credentials are set.
X402_FEED_PRICE	$0.05	Money-formatted ($0.05) or atomic units (50000).
X402_PAYWALL_DESCRIPTION	…	Shown on /, /v1/paywall, and the stats dashboard.
X402_MAX_TIMEOUT_SECONDS	120	Maximum settlement window per call.

Free metadata endpoint (zero cost, no signature required):

curl https://api.seneschal.space/v1/paywall

returns the live network/recipient/price/route table so agents can budget a session before opening a paid request.

Support

• Per-call payments (preferred for agents): pay $0.05 USDC on Base to call GET /v1/premium/opportunities. See /v1/paywall for the live recipient + rails.
• GitHub Sponsors: the Sponsor button at the top of the repo (.github/FUNDING.yml).
• Direct tips: ETH / BTC addresses are surfaced on stats.seneschal.space once the operator sets SENESCHAL_DONATE_ETH / SENESCHAL_DONATE_BTC.
• Questions / allow-list bumps: Telegram @OrknetP.

Seneschal runs on a single Helsinki box; every cent helps keep it online.

License

MIT — see LICENSE.

Operator contact

Seneschal is a single-operator Ethereum block builder and searcher running an rbuilder fork from a co-located server in Helsinki. Builder on-chain extra_data is Seneschal/0.1. Contact @OrknetP on Telegram (checked periodically).