Skip to main content

Prediction market intelligence for agents and traders — Kalshi + Polymarket

Project description

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.pulse()

AI-synthesized plain-English market briefing. Covers top markets by volume, whale activity, price movers, volume spikes, and wide spreads in a single call. Synthesis is powered by Claude Haiku on the server — no LLM setup needed on your end.

pulse = client.pulse(
    venue="all",         # "all" | "kalshi" | "polymarket"
    category="All",      # "All" | "Sports" | "Politics" | "Other"
)
print(pulse["summary"])
# Returns: { summary (plain-English briefing), highlights, meta }

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
pulse() 5
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"

# Market pulse (AI-synthesized briefing)
curl -s -H "X-API-Key: vey_sk_..." \
  "https://api.veynor.xyz/v1/pulse" | jq .summary

# 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
GET /v1/pulse venue, category 5
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

Market pulse

A plain-English briefing synthesized from live data — top markets, whale activity, price movers, volume spikes, and wide spreads in one shot:

veynor pulse
veynor pulse --venue kalshi
veynor pulse --category Sports

Sample output:

  Prediction Market Pulse — Wed May 13 2026
  Data as of: 2026-05-13 14:14:54

  Tennis markets are the real action right now: Pol Martin Tiffon collapsed
  66.5¢ in the last hour to 6.5¢ while Chris Rodesch surged 59¢ on Kalshi,
  indicating live match developments. Whale activity is NO-heavy at $178K
  total notional, anchored by a $34K Manchester City bet...

  Top markets
    Will Bitcoin hit $150k by June 30, 2026?           $5.8M  (POLYMARKET)
    Hantavirus pandemic in 2026?                       $1.1M  (POLYMARKET)
    Starmer out by May 15, 2026?                       $1.1M  (POLYMARKET)
  Whale flow     10 trades  $178K total  NO-heavy
  Biggest mover  Will Pol Martin Tiffon win the match…           -66.5¢ (1h)
  Volume spike   New York Yankees vs. Baltimore Orioles          164.8× ratio
  Wide spread    Will Lillestrøm SK vs. Viking FK end in a draw?  bid/ask 12¢ / 51¢

  5 credits used · veynor.xyz/agents to upgrade

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

Whale following

veynor follow polls the whale feed on an interval and mirrors large trades directly to your Polymarket and/or Kalshi account.

Setup

Polymarket credentials (required):

export POLYMARKET_PRIVATE_KEY=0x...
export POLYMARKET_ADDRESS=0x...

Kalshi credentials (optional — auto-detected if set):

export KALSHI_API_KEY_ID=<uuid>
export KALSHI_PRIVATE_KEY_PATH=/path/to/key.pem
# or inline:
export KALSHI_PRIVATE_KEY="-----BEGIN RSA PRIVATE KEY-----\n..."

Usage

# Start with a dry run first — see what would trade without spending anything
veynor follow --amount 2 --dry-run

# Follow with $5 per copied trade, minimum $15k whale size
veynor follow --amount 5 --min-notional 15000

# Use 2% of balance per trade, $50/day cap, Politics markets only
veynor follow --pct 2 --max-daily 50 --category Politics

# Follow both YES and NO sides, poll every 15 seconds
veynor follow --amount 10 --sides ALL --interval 15

# Explicit venue list (default: auto-detect from env)
veynor follow --amount 3 --venues polymarket --venues kalshi

How it works

  1. On startup, seeds all current whale trades as seen so no historical trades fire.
  2. Every --interval seconds, fetches fresh whale trades from all active venues.
  3. New trades (not seen before) are fingerprinted by (platform, market, side, notional) and persisted to ~/.veynor_seen_trades.json so restarts don't re-fire.
  4. Polymarket trades: looks up the market by name to resolve token_id and neg_risk flag, then executes a market buy.
  5. Kalshi trades: extracts the ticker from the market URL, maps the side (handles team names like "NO KANSAS CITY"), and executes a market buy.
  6. Daily spend is tracked in memory and resets at midnight. Use --max-daily to cap total exposure.

Options

Flag Default Description
--amount 2.0 Fixed USDC per copied trade
--pct % of balance per copied trade (mutually exclusive with --amount)
--min-notional 10000 Only copy trades at or above this size
--category All Filter to Sports, Politics, or Other
--sides YES YES, NO, or ALL
--max-daily 0 Daily USDC spend cap (0 = no cap)
--interval 30 Poll interval in seconds
--venues auto polymarket, kalshi, or both (repeat flag)
--dry-run false Log trades without executing
--verbose false Log every poll cycle, not just new trades

What's new in v1.4.7

  • veynor portfolio — unified cross-venue portfolio view. Shows live balances and open positions across Kalshi and Polymarket in a single command. Auto-detects credentials; shows whichever venues are configured. Polymarket positions include avg price, current price, current value, and unrealized P&L. Kalshi positions show contract count and realized P&L.
  • veynor positions — copy-trading journal for positions opened via veynor follow. Tracks entry price, exit price, and realized P&L per trade.
  • Position tracking in veynor follow — every executed trade is now recorded. Supports automatic exits via --take-profit, --stop-loss, and --max-hold-hours. Positions persist across restarts.

What's new in v1.4.6

  • Internal: position store and exit logic foundation (shipped as part of v1.4.7).

What's new in v1.4.5

  • Kalshi-only followingveynor follow --venues kalshi no longer requires Polymarket credentials. Traders are now initialized only for the venues actually requested. Clear error messages guide Kalshi-only users to set KALSHI_API_KEY_ID and KALSHI_PRIVATE_KEY_PATH instead of showing an irrelevant Polymarket key error.

What's new in v1.4.4

  • Kalshi hotfix — corrects API base URL to external-api.kalshi.com, fixes RSA auth signing (query params excluded from signature path), fixes get_balance() response parsing, and adds find_ticker_by_slug() with team-suffix matching for sports markets. v1.4.3 had broken Kalshi support; upgrade to 1.4.4.

What's new in v1.4.3

  • Whale followingveynor follow daemon mirrors large whale trades to your Polymarket and/or Kalshi account. Persistent dedup, daily spend cap, dry-run mode. Kalshi is auto-detected from env vars.
  • Polymarket minimum contractsmarket_buy now enforces the Polymarket minimum of 5 contracts per order, adjusting size up automatically when needed.
  • Multi-venue following — a single follower instance can watch both Polymarket and Kalshi simultaneously. Use --venues to configure explicitly or let it auto-detect from credentials.

What's new in v1.4.2

  • Market pulseclient.pulse() and veynor pulse CLI command. AI-synthesized plain-English briefing covering top markets, whale flow, price movers, volume spikes, and wide spreads. Powered by Claude Haiku on the server. 5 credits.
  • Stale market filtering — pulse and signals automatically exclude markets past their close time so no expired data surfaces as actionable.
  • Data freshness tracking — pulse response includes meta.data_freshness so you always know how old the underlying scanner data is.

What's new in v1.4.1

  • Kalshi tradingKalshiTrader with market/limit orders on YES and NO, cancel, positions, balance. RSA key pair auth, non-custodial.
  • Price history endpointGET /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 relayPOST /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.

Links

Project details


Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

veynor-1.4.9.tar.gz (52.7 kB view details)

Uploaded Source

File details

Details for the file veynor-1.4.9.tar.gz.

File metadata

  • Download URL: veynor-1.4.9.tar.gz
  • Upload date:
  • Size: 52.7 kB
  • Tags: Source
  • Uploaded using Trusted Publishing? No
  • Uploaded via: twine/6.2.0 CPython/3.10.13

File hashes

Hashes for veynor-1.4.9.tar.gz
Algorithm Hash digest
SHA256 3518a47677083a645c01634fecbe5e14b1cff63558b7b6158c3d1730647345ba
MD5 5b3f9f76700e05f3749ca46a6cef5c70
BLAKE2b-256 a1ada42f1077692c543d2cab79655cd6045685a999b442bfe84f463b0da41339

See more details on using hashes here.

Supported by

AWS Cloud computing and Security Sponsor Datadog Monitoring Depot Continuous Integration Fastly CDN Google Download Analytics Pingdom Monitoring Sentry Error logging StatusPage Status page