Marketplace API · Live on Base mainnet

Multi-venue funding data, pay per request.

Major CEX and DEX perpetuals venues, exposed under one HTTP surface. x402 protocol — no API keys, no rate-limit signups, USDC settlement on Base in seconds.

View endpoints →Listed on agentic.market ↗
Endpoints

Six endpoints, two free, four paid

Free endpoints expose service shape (venue list + per-venue freshness). Paid endpoints return live data — funding rates and top-of-book — priced per request in USDC.

PathPriceDescription
GET/v1/venues/listFreeArray of supported venues with source_id, name, type (cex|dex), tracked symbol count.
GET/v1/venues/healthFreeLiveness + freshness per venue. status ∈ live | stale | down.
GET/v1/funding/current?symbol=BTC$0.001Current funding rates across all venues for the given symbol. Omit symbol to fetch all.
GET/v1/funding/spread/:symbol$0.001Cross-venue spread snapshot — max rate, min rate, spread in bps, source venues.

Base URL: https://api.usenami.io

How it works

x402 — pay per request, no API keys

Your agent doesn't register, doesn't store keys, doesn't deal with rate limits. Each call settles on Base mainnet via the agent's wallet. Three steps end to end.

Step 1

Agent sends request

Plain HTTP GET — no API key, no auth header. Same shape as any REST call.

GET https://api.usenami.io/v1/funding/spread/BTC
Step 2

Server returns 402

HTTP 402 Payment Required. The payment-required header carries a base64-encoded challenge with payTo address, amount in USDC, and network eip155:8453 (Base mainnet).

HTTP/2 402 Payment Required
payment-required: <base64 challenge>
Step 3

Agent retries with signature

Wallet signs an EIP-3009 USDC transferWithAuthorization. Agent retries with X-PAYMENT header. Server validates via Coinbase x402 facilitator → settlement on Base → response delivered.

GET .../v1/funding/spread/BTC
X-PAYMENT: <signed authorization>
Sample code

Call from curl, Python, or TypeScript

curl shows the raw 402 challenge. The Python and TypeScript snippets use the x402 client SDK so wallet signing + retry happens automatically.

bash
# 1. First request (no payment) — server returns 402 Payment Required
curl -i https://api.usenami.io/v1/funding/spread/BTC

# HTTP/2 402
# payment-required: <base64-encoded x402 challenge>
# (decode → contains payTo address, amount in USDC, network eip155:8453)

# 2. Sign the EIP-3009 transferWithAuthorization with your wallet,
#    then retry with the X-PAYMENT header (use a client SDK below
#    rather than rolling your own signing).

SDK package names + import paths above reflect current x402 client conventions — cross-check against the upstream x402 quickstart ↗ before integrating.

Coverage

Major CEX + DEX — coverage no commodity provider offers

One paid call covers every supported venue. Includes the full Hyperliquid HIP-3 cluster (HyENA, DreamCash, Felix, Kinetiq, Ventuals, trade.xyz) plus six other DEX perpetual surfaces and a dozen centralized venues.

Centralized · 12 venues
BinanceBybitOKXBitgetGate.ioMEXCHTXKuCoinBingXPhemexCrypto.comDeribit
Decentralized · 17 venues
HyperliquidHyENADreamCashFelixKinetiqVentualstrade.xyzParadexdYdXApeX OmniLighterAsterEdgeXGRVTVariationalHibachiExtended
Honest data, not packaged alpha

What we sell — and what stays internal

What you get
  • Raw multi-venue funding rates
  • Cross-venue spread snapshots
  • Venue freshness + liveness
What stays internal
  • Signal logic + decision rules
  • Position sizing models
  • Exit timing + stop-out heuristics
  • Slippage + execution telemetry
  • Calibration parameters

We sell the inputs that anyone could in principle aggregate themselves — but no commodity data vendor offers this set of venues. The processing layer that turns these inputs into decisions is our own and is not for sale.

Pricing

Floor pricing, gentle escalation

Current prices ($0.001 – $0.005) are floor tier. When we raise an existing endpoint price, we cap the change at +25% per cadence and publish a changelog entry. New premium endpoints can launch at a higher tier; existing prices are grandfathered. x402 has zero lock-in — switching providers takes one URL swap — so the pricing discipline is on us, not contractual.

Next steps

Get started

agentic.market ↗

Service catalog for x402-enabled APIs. Discover the marketplace API alongside other x402 services.

x402 protocol docs ↗

Spec, client SDKs, facilitator details, and wallet integration patterns from Coinbase.

@usenami_io ↗

Pricing changelog, new endpoint announcements, marketplace updates.

Status

Live freshness per venue and end-to-end pipeline health.