cnghockey/sats4ai-l402-examples

Code examples for integrating with Sats4AI's L402 API — 33+ pay-per-use AI tools with Bitcoin Lightning.
No signup. No API keys. No KYC. Just HTTP requests + Lightning payments.
## What is L402?
L402 lets you pay for API access with Bitcoin instead of signing up for accounts. The flow:
1. Send a request → server returns 402 Payment Required with a Lightning invoice
2. Pay the invoice → your wallet gives you a preimage (proof of payment)
3. Resend with proof → Authorization: L402 :
That's it. Works with any HTTP client and any Lightning wallet.
## Quick Start
### curl (simplest)
bash
# Step 1: Request → get 402 + invoice
curl -s -D - -o /dev/null -X POST https://sats4ai.com/api/l402/generate-image \
-H "Content-Type: application/json" \
-d '{"input": {"prompt": "a cat in space"}}' 2>&1 | grep -i www-authenticate
# Step 2: Pay the invoice with any Lightning wallet
# Step 3: Resend with proof
curl -X POST https://sats4ai.com/api/l402/generate-image \
-H "Content-Type: application/json" \
-H "Authorization: L402 : " \
-d '{"input": {"prompt": "a cat in space"}}'
See examples/curl/ for complete scripts.
### Python
bash
pip install requests
python
from lib.l402_client import L402Client
client = L402Client()
# Get invoice
invoice_data = client.request("generate-image", {"input": {"prompt": "a cat in space"}})
print(f"Pay this invoice: {invoice_data['invoice']}")
# After paying, submit proof
preimage = input("Enter preimage from wallet: ")
result = client.complete(invoice_data, preimage)
See examples/python/ for all services.
### Node.js
javascript
// Node.js 18+ (built-in fetch, no dependencies needed)
import { requestL402, completeL402 } from "./lib/l402-client.mjs";
// Get invoice
const challenge = await requestL402("generate-image", {
input: { prompt: "a cat in space" },
});
console.log(Pay this invoice: ${challenge.invoice});
// After paying, submit proof
const preimage = "your_preimage_here";
const result = await completeL402(challenge, { input: { prompt: "a cat in space" } }, preimage);
See examples/node/ for all services.
## Available Services
### AI Generation
| Endpoint | Description | Price |
| generate-image | Image from text prompt | 100-200 sats |
| generate-text | AI chat / text completion | ~1 sat/100 chars |
| generate-video | Video from text (async) | 300-550 sats/sec |
| animate-image | Video from image (async) | 100 sats/sec |
| generate-music | Music with AI vocals | 100 sats |
| generate-3d-model | Photo to 3D GLB (async) | 350 sats |
| translate-text | Translate (119 languages) | ~1 sat/1000 chars |
### Audio & Speech
| Endpoint | Description | Price |
| text-to-speech | Text to audio (467 voices, 29 languages) | 300 sats |
| transcribe-audio | Audio to text (async) | 10 sats/min |
| clone-voice | Clone voice from audio | 7,500 sats |
| epub-audiobook | Book to audiobook (async) | 500+ sats |
### Image Processing
| Endpoint | Description | Price |
| remove-background | Remove background, transparent PNG (BiRefNet) | 5 sats |
| upscale-image | Upscale 2x/4x with Real-ESRGAN | 5 sats |
| restore-face | Restore blurry/damaged faces (CodeFormer) | 5 sats |
| colorize-image | Colorize B&W photos (DDColor) | 5 sats |
| deblur-image | Remove camera-shake blur (NAFNet) | 20 sats |