veynor 1.4.1

Prediction market intelligence for agents and traders — Kalshi + Polymarket

veynor

Python client for the Veynor prediction market intelligence API.

Cross-venue data and trading across Kalshi and Polymarket: whale trades, smart money signals, arb opportunities, market search, price history, and order execution — in a single import.

pip install veynor

---

Quickstart

import veynor

client = veynor.Client(api_key="vey_sk_...")

# Whale trades across both venues
whales = client.whales(venue="all", min_notional=10_000)
for t in whales["trades"]:
    print(t["platform"], t["market"], t["side"], f"${t['notional']:,.0f}")

# Arb opportunities between Kalshi and Polymarket
arb = client.signals(signal_type="arb_opportunities")
for opp in arb["arb_opportunities"]:
    print(opp)

Get a free API key at veynor.xyz/agents.

---

Authentication

Pass your key directly or via environment variable:

# Option 1: direct
client = veynor.Client(api_key="vey_sk_...")

# Option 2: environment variable
# export VEYNOR_API_KEY=vey_sk_...
client = veynor.Client()

---

Methods

client.whales()

Recent large trades across Kalshi and Polymarket.

whales = client.whales(
    venue="all",           # "all" | "kalshi" | "polymarket"
    min_notional=8_000,    # minimum trade size in USD
    category="Politics",   # "All" | "Sports" | "Politics" | "Other"
    limit=20,
)
# Returns: { summary, trades: [...], meta }

client.top_markets()

Top markets by 24-hour volume.

markets = client.top_markets(
    venue="all",
    category="All",
    limit=10,
)
# Returns: { summary, kalshi: [...], polymarket: [...], meta }

client.search()

Search markets by keyword across both venues. Results include current YES price, 24-hour volume, end date, spread, and liquidity.

results = client.search("fed rate", venue="all", limit=10)
# Returns: { summary, polymarket: [...], kalshi: [...], meta }
# Each market includes: title, yes_price, volume_24h, end_date, spread_cents, liquidity, url

client.market()

Full details for a specific market.

# Polymarket: use condition ID
m = client.market("polymarket", "0x1234...")

# Kalshi: use ticker
m = client.market("kalshi", "KXNBA-25-LAL")

# Returns: { summary, market: {...}, meta }

client.signals()

Alpha signals: wide spreads, price movers, cross-venue arb.

signals = client.signals(
    signal_type="all",   # "all" | "wide_spreads" | "price_movers" | "arb_opportunities"
    limit=10,
)
# Returns: { summary, wide_spreads, price_movers, arb_opportunities, meta }

client.positions()

Open positions for a Polymarket wallet address. No private key required.

for p in client.positions("0xabc..."):
    print(p["title"], p["cashPnl"])

client.usage()

Check your credit balance. Always free.

u = client.usage()
print(u["tier"], u["credits_remaining"])

---

Credit costs

Method	Credits
whales()	2
top_markets()	1
search()	1
market()	1
signals()	3
price_history()	1
usage()	0

Free tier: 100 credits/month. Upgrade at veynor.xyz/agents.

---

Exceptions

from veynor import VeynorError, AuthError, RateLimitError

try:
    whales = client.whales()
except AuthError:
    print("Invalid or expired API key")
except RateLimitError:
    print("Rate limit hit — slow down or upgrade tier")
except VeynorError as e:
    print(f"API error {e.status_code}: {e}")

---

REST API

All SDK methods map directly to REST endpoints at https://api.veynor.xyz. Pass your key via X-API-Key header.

# Whale trades
curl -s -H "X-API-Key: vey_sk_..." \
  "https://api.veynor.xyz/v1/whale-trades?min_notional=10000&limit=10"

# Top markets by 24h volume
curl -s -H "X-API-Key: vey_sk_..." \
  "https://api.veynor.xyz/v1/markets/top?limit=10"

# Search markets
curl -s -H "X-API-Key: vey_sk_..." \
  "https://api.veynor.xyz/v1/markets/search?q=fed+rate"

# Specific market
curl -s -H "X-API-Key: vey_sk_..." \
  "https://api.veynor.xyz/v1/markets/polymarket/0x1234..."
curl -s -H "X-API-Key: vey_sk_..." \
  "https://api.veynor.xyz/v1/markets/kalshi/KXNBA-25-LAL"

# Price history (~1h rolling, 60s snapshots)
curl -s -H "X-API-Key: vey_sk_..." \
  "https://api.veynor.xyz/v1/markets/polymarket/0x1234.../history"
curl -s -H "X-API-Key: vey_sk_..." \
  "https://api.veynor.xyz/v1/markets/kalshi/KXNBA-25-LAL/history"

# Alpha signals
curl -s -H "X-API-Key: vey_sk_..." \
  "https://api.veynor.xyz/v1/signals?signal_type=arb_opportunities"

# Credit usage
curl -s -H "X-API-Key: vey_sk_..." \
  "https://api.veynor.xyz/v1/usage"

Endpoint	Params	Credits
GET /v1/whale-trades	venue, min_notional, category, limit	2
GET /v1/markets/top	venue, category, limit	1
GET /v1/markets/search	q (required), venue, limit	1
GET /v1/markets/:venue/:id	—	1
GET /v1/markets/:venue/:id/history	—	1
GET /v1/signals	signal_type, limit	3
POST /v1/credentials/kalshi	kalshi_key_id, private_key	0
GET /v1/credentials/kalshi	—	0
DELETE /v1/credentials/kalshi	—	0
POST /v1/trade/kalshi	ticker, action, side, count, price	2
POST /v1/trade/submit	order, signature, wallet	2
GET /v1/usage	—	0

---

CLI

Every API method is also available as a shell command. Set your key once:

export VEYNOR_API_KEY=vey_sk_...

Search markets

veynor search "fed rate"
veynor search "bitcoin" --limit 20
veynor search "election" --venue kalshi

Output shows YES price, 24-hour volume, and platform for each result:

  [polymarket]  YES  62¢  $  1,234,567/24h  Will the Fed cut rates in June?
  [kalshi]      YES  58¢  $    412,300/24h  Fed rate cut — June 2025

Add --json for machine-readable output:

veynor search --json "bitcoin" | jq '.results[].yes_price'

Whale trades

veynor whales
veynor whales --min-notional 50000
veynor whales --venue kalshi --limit 5

Top markets

veynor top
veynor top --venue polymarket --limit 20

Signals

veynor signals                          # all signals
veynor signals --type wide_spreads
veynor signals --type arb_opportunities
veynor signals --type price_movers

Market detail

veynor market polymarket <condition_id>
veynor market kalshi KXNBA-25-LAL
veynor market kalshi KXNBA-25-LAL --json

Credit usage

veynor usage

---

Use in a Jupyter notebook

import veynor, pandas as pd

client = veynor.Client()
data   = client.whales(min_notional=15_000, limit=50)
df     = pd.DataFrame(data["trades"])
df[["market", "side", "notional", "platform"]].sort_values("notional", ascending=False)

---

Kalshi order execution

Place orders on Kalshi directly using your personal API key pair. All signing happens locally — your private key never leaves your machine.

1. Install trade dependencies

pip install veynor[trade]

This adds cryptography (for RSA signing) on top of the base install.

2. Generate a key pair and register it

# Generate RSA key pair
openssl genrsa -out kalshi_key.pem 2048
openssl rsa -in kalshi_key.pem -pubout   # copy this output

Paste the public key at kalshi.com/profile/api-keys and copy the resulting Key ID (a UUID).

3. Set credentials

export KALSHI_API_KEY_ID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
export KALSHI_PRIVATE_KEY_PATH=/path/to/kalshi_key.pem

Or pass the PEM text directly:

export KALSHI_PRIVATE_KEY="-----BEGIN RSA PRIVATE KEY-----\n..."

4. Trade

from veynor import KalshiTrader

trader = KalshiTrader()   # reads env vars automatically

# Account
print(trader.get_balance())    # { cash_usd, cash_cents, ... }
print(trader.get_positions())  # open positions

# Market buy — spend $50 on YES
result = trader.market_buy("KXNBA-25JUL05-T204", side="YES", amount_usd=50.0)
print(result["order_id"], result["status"])

# Limit buy — 100 contracts at 65¢
result = trader.limit_buy("KXNBA-25JUL05-T204", side="YES", price=0.65, count=100)

# Buy NO side
result = trader.limit_buy("KXNBA-25JUL05-T204", side="NO", price=0.40, count=50)

# Market sell
result = trader.market_sell("KXNBA-25JUL05-T204", side="YES", count=100)

# Limit sell
result = trader.limit_sell("KXNBA-25JUL05-T204", side="YES", price=0.72, count=100)

# Cancel an open order
trader.cancel_order(order_id)

# Open orders
orders = trader.get_open_orders()
orders = trader.get_open_orders(ticker="KXNBA-25JUL05-T204")

Via the REST API

Register credentials once (encrypted at rest — never returned in any response):

curl -X POST https://api.veynor.xyz/v1/credentials/kalshi \
  -H "X-API-Key: vey_sk_..." \
  -H "Content-Type: application/json" \
  -d '{
    "kalshi_key_id": "your-uuid",
    "private_key": "-----BEGIN RSA PRIVATE KEY-----\n..."
  }'

# Check status
curl -H "X-API-Key: vey_sk_..." \
  https://api.veynor.xyz/v1/credentials/kalshi

# Remove stored credentials
curl -X DELETE -H "X-API-Key: vey_sk_..." \
  https://api.veynor.xyz/v1/credentials/kalshi

Then place orders against your own Kalshi account:

# Limit buy — 100 YES contracts at 65¢
curl -X POST https://api.veynor.xyz/v1/trade/kalshi \
  -H "X-API-Key: vey_sk_..." \
  -H "Content-Type: application/json" \
  -d '{"ticker": "KXNBA-25JUL05-T204", "action": "buy", "side": "YES", "count": 100, "price": 0.65}'

# Market sell
curl -X POST https://api.veynor.xyz/v1/trade/kalshi \
  -H "X-API-Key: vey_sk_..." \
  -d '{"ticker": "KXNBA-25JUL05-T204", "action": "sell", "side": "YES", "count": 100, "order_type": "market"}'

Each user's trades execute on their own Kalshi account. Credentials are AES-256-GCM encrypted at rest and scoped to your Veynor API key.

Errors and troubleshooting

Error	Fix
No Kalshi credentials registered	Call POST /v1/credentials/kalshi or set env vars
cryptography package not installed	Run pip install veynor[trade]
Kalshi API error (401)	Check that your Key ID matches the registered public key
Kalshi API error (403)	API key may be read-only — enable trading in Kalshi dashboard

---

Polymarket order execution

Place orders on Polymarket directly from Python. All signing happens locally — your private key never leaves your machine and is never sent to Veynor's servers.

Supports Polymarket V2 (live April 28, 2026): native EIP-712 signing, pUSD collateral, proxy wallet and plain EOA flows.

1. Install trade dependencies

pip install veynor[trade]

2. Set credentials

export POLYMARKET_PRIVATE_KEY=0x...   # required — your EOA private key
export POLYMARKET_ADDRESS=0x...       # optional — proxy wallet address (Magic users)

If you set POLYMARKET_ADDRESS, orders are placed via your proxy wallet (signatureType 1). Without it, your EOA signs directly (signatureType 0).

3. Trade

# Check pUSD balance
veynor trade balance

# Open positions
veynor trade positions

# Market buy $50 of YES shares
veynor trade buy <token_id> --amount 50

# Neg-risk market (most multi-outcome markets)
veynor trade buy <token_id> --amount 50 --neg-risk

# Sell 100 shares
veynor trade sell <token_id> --shares 100

# Copy the latest whale trade
veynor trade copy
veynor trade copy --min-notional 50000 --amount 200 --yes

Python API

from veynor import PolymarketTrader

trader = PolymarketTrader()
print(trader.get_balance())

result = trader.market_buy(token_id, amount_usdc=50.0, neg_risk=True)
result = trader.limit_buy(token_id, price=0.72, size=10.0)
result = trader.market_sell(token_id, amount_shares=10.0)
result = trader.limit_sell(token_id, price=0.80, size=10.0)
orders = trader.get_open_orders()
trader.cancel_order(order_id)

Via the REST API (no-custody relay)

Sign the order with your wallet, pass the signature to Veynor. Your private key never touches our servers:

curl -X POST https://api.veynor.xyz/v1/trade/submit \
  -H "X-API-Key: vey_sk_..." \
  -H "Content-Type: application/json" \
  -d '{
    "order":     { ...eip712_order_fields... },
    "signature": "0x...",
    "wallet":    "0x...",
    "order_type": "GTC"
  }'

Errors and troubleshooting

Error	Fix
No private key found	Set POLYMARKET_PRIVATE_KEY
Failed to derive API credentials	Key must be a valid hex string starting with 0x
Trading requires extra packages	Run pip install veynor[trade]
Trading restricted in your region	Polymarket geo-blocks certain IPs — use a non-restricted server
Order status unmatched	Insufficient liquidity — try a smaller amount

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What's new in v1.4.0

• Kalshi trading — KalshiTrader with market/limit orders on YES and NO, cancel, positions, balance. RSA key pair auth, non-custodial.
• Price history endpoint — GET /v1/markets/:venue/:id/history returns rolling ~1h of 60-second price snapshots with computed 5m/15m/1h moves.
• Market index enriched — search results now include end_date, spread_cents, and liquidity on every market.
• Polymarket signed-order relay — POST /v1/trade/submit for agents that sign locally and route through Veynor for builder attribution.
• Per-user credential storage — Kalshi keys stored AES-256-GCM encrypted per Veynor API key. Each user trades their own account.

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Links

• Register for an API key
• MCP server — connect directly from Claude Desktop or Cursor
• Web app — whale feed, signals, trade interface