SatRank — Lightning trust + audit oracle

SatRank

Lightning trust oracle for AI agents on L402. Bitcoin-pure.

What this does

• Crawls the L402 ecosystem (l402.directory + RSS + DNS) to build a catalogue of paid endpoints.
• Probes each endpoint, classifying outcomes across 5 stages: challenge / invoice / payment / delivery / quality.
• Scores every (endpoint, stage) pair as a streaming Beta(α, β) posterior. The end-to-end success probability is the product of stage means.
• Ranks candidates on POST /api/intent (paid 2 sats via L402): an agent passes a category + budget + SLA, gets back the top-K endpoints with full Bayesian breakdown.
• Publishes signed Nostr trust assertions (kind 30782) so any agent can cache / verify SatRank's output offline.

Public endpoints

Doc surfaces:

GET  /                                 landing page (static HTML)

GET /methodology technical reference (static HTML) GET /api API reference (static HTML) GET /openapi.json OpenAPI 3.0 spec (machine-readable)

Functional API (nine routes — POST /api/intent is the only L402-gated one):

POST /api/intent                       paid, 2 sats via L402

POST /api/deposit free, mint a multi-use deposit macaroon (10–10000 sats, 30-day TTL) GET /api/deposit/:macaroon_id free, read remaining balance GET /api/services/:url_hash free, per-endpoint score snapshot GET /api/services/categories free, list of catalogue categories GET /api/services/best free, top-3 per category (5-min cache) GET /api/oracle/budget free, last 24h revenue + paid-probe spend GET /health free, liveness GET /.well-known/satrank-key free, oracle pubkey for offline verify

Deposit macaroons let an agent pre-pay N sats once and use the bearer preimage across many /api/intent calls without a Lightning round-trip per call. Authorization: L402 deposit_ : .

MCP

Three tools for any MCP-compatible AI runtime (Claude Code, Cursor, Codex, n8n):

intent              forwards POST /api/intent (paid)

get_endpoint_score forwards GET /api/services/:url_hash (free) verify_assertion offline Schnorr verification of kind 30782 (no network)

Install in Claude Code:

claude mcp add satrank -- npx -y satrank-mcp

Self-hosters point SATRANK_API_BASE at their own deployment.

Architecture

14 source files + 4 doc surfaces (3 HTML pages + OpenAPI spec). Read top-to-bottom in 30 minutes.

src/

├── types.ts Stage, Posterior, Endpoint, Observation ├── config.ts zod env schema, parsed once at boot ├── logger.ts JSON-line stdout ├── db.ts pg Pool + idempotent schema bootstrap ├── schema.sql 9 tables in ONE file (no migrations folder) ├── lnd.ts minimal LND REST client (addInvoice + payInvoice) ├── ssrf.ts RFC1918 + link-local + IPv6 ULA URL guard ├── nostr.ts kind 30782 sign + publish + offline verify ├── scoring.ts Beta(α,β) per stage, Wilson CI95, ranker ├── probe.ts HTTP probe with optional L402 pay ├── crawler.ts l402.directory + RSS + DNS + cron ├── api.ts Express; 9 functional routes + 4 doc surfaces, native L402 paid gate, deposit credits ├── mcp.ts MCP server, 3 tools, ships verbatim to npm ├── landing.html static landing served at GET / ├── methodology.html technical reference served at GET /methodology ├── api-reference.html API reference served at GET /api ├── openapi.json OpenAPI 3.0 spec served at GET /openapi.json └── index.ts boot + shutdown

Run it

cp .env.example .env

minimum: set DATABASE_URL

npm install npm run build npm start

For paid probes + paid /api/intent gate, set LND_REST_URL + LND_MACAROON_HEX + L402_MACAROON_SECRET. For Nostr trust assertions, set NOSTR_PRIVATE_KEY.

Scoring math

For each (endpoint, stage), maintain a Beta(α, β) posterior with α₀ = β₀ = 1 (uniform prior). On every observation:

• success → α += 1
• failure → β += 1

Stage mean: α / (α+β). 95% credible interval via Wilson (closed-form). End-to-end success: ∏ stage_means across the 5 stages, assuming stage independence.

is_meaningful is true iff the challenge stage has at least MEANINGFUL_N_OBS_MIN observations. The challenge stage is observed on every probe (free or paid), so its n_obs converges fastest. p_e2e remains the honest end-to-end product separately.

License

AGPL-3.0