我推出兩個供 AI 智能體使用的 L402 API：10 sats 獲取清理後的數據，2,500 sats 查詢 mempool 交易分析
I launched two L402 APIs for AI agents — clean data for 10 sats, mempool forensics for 2,500
作者推出兩個可透過 Bitcoin Lightning 付款的 L402 API：10 sats 可將原始網頁內容轉為結構化 JSON，2,500 sats 可分析 Bitcoin 交易並比較 BTC 即時價格，以識別套利價差。服務無需帳戶或 API keys，使用者付款後提交付款證明即可取得數據；目前仍在免費託管方案上運行，且沒有付費客戶。
AI agents can write code, browse the web and run tools — but the moment they need to pay for an API, the flow collapses into human infrastructure: signups, API keys, credit cards, monthly plans.
L402 fixes that. The payment is the credential. So I built two production-light APIs that any agent (or human) can consume autonomously over Bitcoin Lightning, and put them live:
🔗 https://l402-ai-gateway.onrender.com
What's for sale
| Endpoint | Price | What it does |
|---|---|---|
POST /v1/data/clean-scrape |
10 sats | Takes raw web content and returns clean, structured JSON an LLM can consume directly |
POST /v1/forensic/mempool-arbitrage-audit |
2,500 sats | Analyzes a real Bitcoin transaction (fee rate, RBF signaling, inputs/outputs, confirmations) using live mempool.space data, and compares live BTC prices across Kraken, Coinbase and Bitstamp to flag arbitrage spreads |
No accounts. No keys. You call, you get a 402, you pay the Lightning invoice, you retry with the proof, you get the data.
How the paywall works
The middleware is protocol-standard, not a custom hack:
- Request without payment →
402 Payment Requiredwith aWWW-Authenticate: L402 macaroon="…", invoice="lnbc…"header (plus the same data as JSON). - The macaroon is HMAC-chained and attenuated by endpoint, payment hash, amount and expiry — a token bought for the 10-sat endpoint is rejected on the 2,500-sat one.
- Pay the invoice (issued by a real LNbits wallet) → you get the preimage.
- Retry with
Authorization: L402 <macaroon>:<preimage>→ the server verifiessha256(preimage) == payment_hashlocally and serves the result.
It works out of the box with standard tooling like Lightning Labs' lnget — point it at an endpoint and the pay-and-retry cycle is automatic.
Discovery is built in too: a machine-readable manifest at /.well-known/l402.json, public pricing at /pricing, interactive OpenAPI docs at /docs, and the service announces itself on Nostr with NIP-89 handler events (kind 31990) so agents can find it without me doing marketing.
Under the hood: FastAPI, an in-memory TTL cache (repeat calls are cheap), and live upstream data — nothing in the forensic report is mocked.
Honest limitations
This is a launch, not a victory lap:
- It runs on a free hosting tier that sleeps when idle — the first call can take a few seconds to wake up.
- The receiving wallet is a custodial LNbits demo instance. Fine for the first sats, not where I'd keep real revenue.
- It currently has zero paying customers. That's why this post exists.
Try it / break it
The cheapest call costs 10 sats — less than a cent. If you're building agents, trading bots or L402 tooling, I'd genuinely love for you to:
- Hit the endpoint and run the full pay flow.
- Tell me what the output is missing for your use case.
- If it fits, I'm helping the first 10 builders integrate it for free (the calls themselves stay at list price — a real 10-sat payment is the feedback signal I care about).
Docs and manifest are public, the code structure is a standard FastAPI service, and the paywall answers with a real invoice from a real wallet. The machine economy needs services that are actually buyable by machines — this is my first one.
What should the third endpoint be?
來源：DEV Community · dev.to