REST · x402 · Base Mainnet

Endpoints &
Pricing

A single Express API hosted on Google Cloud Functions. One free health endpoint, four x402-gated data endpoints. No API keys. No accounts. Pay per call in USDC.

Base URL

https://us-central1-fourmonth-73efe.cloudfunctions.net/api

Custom domain mineflowtrack.com coming soon. All paths below are relative to this base.

Endpoints

Five routes, two tiers

Method Path Auth Price Description
GET /health None Free API status, version, uptime. Always returns 200.
GET /benchmark/gold x402 $0.10 USDC USGS gold commodity summary — mine production, reserves, price, global context.
GET /benchmark/silver x402 $0.10 USDC USGS silver commodity summary — industrial use, mine output, reserves, price.
GET /benchmark/copper x402 $0.10 USDC USGS copper commodity summary — energy transition demand, mine production, reserves.
GET /runs x402 $0.10 USDC Paginated list of attested field run logs from the ultrasound gravity separation field season. Filterable.

Pricing

Flat rate, no surprises

✓

Free tier

GET /health always returns 200 at no cost. Use it to verify the API is live, test your client setup, or monitor uptime.

No wallet required.

💸

$0.10 USDC per call

All data endpoints are gated with x402. Each successful call costs exactly $0.10 USDC settled on Base mainnet via CDP Facilitator.

Payment recipient:
0x750977976Ab85A4Ce5AAbb2e1a9fc80a633f2769

Run logs endpoint

Query parameters for /runs

Parameter Type Default Description
feed_type string — Filter by feed type (e.g. placer_concentrate).
frequency_khz number — Filter by ultrasound frequency in kHz (e.g. 28, 40).
min_recovery_pct number — Return only runs with recovery rate ≥ this value.
attested_only boolean false If true, return only runs with an EAS attestation UID.
limit number 20 Number of results per page. Max 100.
offset number 0 Pagination offset.

Examples

curl examples

1. Free health check

curl https://us-central1-fourmonth-73efe.cloudfunctions.net/api/health

2. Trigger the 402 gate (expected response)

curl -i https://us-central1-fourmonth-73efe.cloudfunctions.net/api/benchmark/copper

Returns HTTP/1.1 402 Payment Required with a machine-readable USDC offer in the body. This is correct — the gate is working.

3. Filtered run logs (after paying via x402 client)

curl -H "X-PAYMENT: <signed-payment-header>" \ "https://us-central1-fourmonth-73efe.cloudfunctions.net/api/runs?feed_type=placer_concentrate&attested_only=true&limit=10"

How payment works

x402 protocol flow

01 — Request

HTTP GET

Call any gated endpoint. No auth header required initially.

02 — Gate

402 Response

Server returns 402 Payment Required with USDC offer: $0.10 on Base.

03 — Pay

EIP-3009 Sign

x402 client signs the authorization and sends payment on Base mainnet.

04 — Data

Full Response

CDP Facilitator verifies. USDC settles. You receive data + EAS UID + IPFS CID.

Compatible with x402-compatible clients — works with Claude Desktop, Cursor, and any agent using the x402 TypeScript or Python SDK.