SPREDD TERMINAL — Unified Prediction Market API

spredd@terminal:~$ cat /etc/motd

███████╗██████╗ ██████╗ ███████╗██████╗ ██████╗ ██╔════╝██╔══██╗██╔══██╗██╔════╝██╔══██╗██╔══██╗ ███████╗██████╔╝██████╔╝█████╗ ██║ ██║██║ ██║ ╚════██║██╔═══╝ ██╔══██╗██╔══╝ ██║ ██║██║ ██║ ███████║██║ ██║ ██║███████╗██████╔╝██████╔╝ ╚══════╝╚═╝ ╚═╝ ╚═╝╚══════╝╚═════╝ ╚═════╝ T E R M I N A L

One API key. Every prediction market. Full execution.

Market data, order books, quotes, and on-chain trade execution across Kalshi, Polymarket, Myriad, Opinion, and Limitless. One endpoint. Normalized schema. 5 chains.

[ENTER] GET API KEY [D] DOCUMENTATION [F] LIVE FEED

WHAT YOU GET API

GET /v1/markets

Search, filter, and browse markets across all 5 platforms. Normalized schema — same fields regardless of source. Order books with bid/ask depth and spread.
POST /v1/trading/quote

Get a real-time price quote on any market. Input amount, expected output tokens, price per token, price impact, and fee — before you commit.
POST /v1/trading/prepare

Returns unsigned transactions ready for client-side signing. Approval + trade in one response. You sign with your own wallet — keys never leave your machine.
POST /v1/trading/execute

Full server-side execution. Send your private key (used in-memory, never stored), Spredd signs and submits on-chain. Get back tx hash and explorer link.
GET /v1/arbitrage

Cross-platform spread detection. Finds the same question priced differently across platforms. Buy low on one, sell high on another.
WS /v1/feed/ws

Real-time WebSocket stream. Market snapshots every 5 seconds across all platforms. Canary signal for staleness detection. Pro tier and above.

TRADING FLOW EXEC

Browse & Search

GET /v1/markets — list all markets across all platforms. Filter by platform, search by keyword, check order books. Same schema everywhere. Free tier.

Quote

POST /v1/trading/quote — get real-time pricing before committing. See exactly what you'll pay, what you'll receive, and the 0.25% fee. No on-chain cost.

Execute

Choose your path: /prepare returns unsigned transactions for client-side signing (recommended). /execute signs and submits on-chain for you. Either way — one API call, any platform, any chain.

CHAINS NET

Polygon

POLYMARKET

Solana

KALSHI

Base

LIMITLESS

Abstract

MYRIAD

BSC

OPINION (DATA)

COMING

PRICING TIERS

Free

60 requests/min

10K requests/month

5 trades/min

Markets, search, order books

No trading

No feed/WebSocket

Builder

$79/mo

300 requests/min

100K requests/month

30 trades/min

Everything in Free +

Trading (quote/prepare/execute)

Positions tracking

Arbitrage detection

Pro

$199/mo

1,000 requests/min

1M requests/month

100 trades/min

Everything in Builder +

Feed endpoints

WebSocket real-time stream

Feed

$499/mo

3,000 requests/min

10M requests/month

Data only (no trading)

Everything in Pro +

SEDA oracle access

Priority support

0.25% (25 bps) fee on all trade execution. Included in every quote.

API QUICKSTART REST

# Sign up and get your API key

$ curl -X POST https://api.spreddterminal.com/v1/auth/signup \
  -H "Content-Type: application/json" \
  -d '{"email": "you@company.com"}'

$ curl -X POST https://api.spreddterminal.com/v1/auth/api-keys \
  -H "Content-Type: application/json" \
  -d '{"account_id": "YOUR_ID", "tier": "builder"}'

# Browse markets across all platforms

$ curl "https://api.spreddterminal.com/v1/markets?search=bitcoin&limit=5" \
  -H "X-API-Key: sprdd_pk_..."

# Response — normalized schema, every platform
[{
  "platform": "polymarket",
  "market_id": "0x1234...",
  "title": "Bitcoin above $150K by EOY?",
  "yes_price": 0.41,
  "no_price": 0.59,
  "volume": 4100000,
  "chain": "polygon",
  "is_active": true
}]

# Get a quote — see price before you commit

$ curl -X POST https://api.spreddterminal.com/v1/trading/quote \
  -H "X-API-Key: sprdd_pk_..." \
  -H "Content-Type: application/json" \
  -d '{"platform":"polymarket","market_id":"0x1234...","outcome":"yes","side":"buy","amount":100}'

{
  "price_per_token": 0.41,
  "expected_output": 243.9,
  "fee_amount": 0.25,
  "fee_bps": 25
}

# Execute — one call, any platform, any chain

$ curl -X POST https://api.spreddterminal.com/v1/trading/execute \
  -H "X-API-Key: sprdd_pk_..." \
  -H "Content-Type: application/json" \
  -d '{"platform":"polymarket","market_id":"0x1234...","outcome":"yes","side":"buy","amount":100,"wallet_address":"0x...","private_key":"0x..."}'

{
  "tx_hash": "0xabc123...",
  "status": "confirmed",
  "explorer_url": "https://polygonscan.com/tx/0xabc123..."
}

FAQ HELP

What is Spredd Terminal?▶

A unified API for prediction markets. One API key gives you market data, order books, price quotes, and on-chain trade execution across Kalshi, Polymarket, Myriad, Opinion Labs, and Limitless. Every response uses the same normalized schema regardless of which platform the data comes from.

Can I actually execute trades through the API?▶

Yes. Three options: /quote gives you pricing without committing. /prepare returns unsigned transactions you sign client-side with your own wallet. /execute handles signing and on-chain submission for you (private key used in-memory only, never stored). Builder tier ($79/mo) and above.

What does the 0.25% fee cover?▶

The 25 basis point fee is applied to trade execution only — not market data requests. It covers transaction routing, gas optimization, and cross-chain execution infrastructure. The fee amount is shown in every quote response before you commit.

Do I need API keys for each platform?▶

No. Spredd handles all platform credentials. You get one API key (sprdd_pk_...) and it works across all 5 platforms. Optionally, Polymarket builders can link their own builder account for volume attribution, but it's not required.

Is the free tier actually free?▶

Yes. 60 requests per minute, 10,000 requests per month. Full access to market data, search, and order books. No credit card required. Trading requires Builder tier ($79/mo) or higher.

How does the WebSocket feed work?▶

Connect to wss://api.spreddterminal.com/v1/feed/ws with your API key. You'll receive market snapshots every 5 seconds across all platforms, plus a canary signal for staleness detection. Requires Pro tier ($199/mo) or higher.