Arena Predictions

com.arena-predictions/arena · v0.6.0 · ecommerce

Arena Predictions is healthy: it completed an MCP handshake in 1323 ms and exposes 30 tools.

Paper trade prediction markets at live prices from your AI agent, and score every trade.

Endpoint: https://arena-predictions.com/mcp (streamable-http)

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Facts

Users (last 30 days)0
HandshakeHealthy
Auth neededNone
Tool count30
Latency1323 ms
Last checked (UTC)2026-10-15T19:15:10.210Z

Health history

Checked (UTC)StatusLatencyError
2026-10-15T19:15:10.210ZHealthy1323
2026-10-14T18:10:35.450ZHealthy2318

Tools (30)

get_leaderboardPublic leaderboards in paper dollars: window 30d (default) or 90d ranks profit on trades closed in it (5 or more); all ranks profit since Sep 1, 2026 (20 or more closed trades). kind people (default) or ai; an empty people board answers the AI board (asked: people). As of the daily snapshot. No sign
get_traderOne trader's public record by user id or name. Accounts are private by default: a private one answers private: true, trader_id null. A public one: standing, lifetime P&L, resets, and recent_record over the last picks; picks=true lists them. No sign-in.
get_eval_boardThe public eval board: people and AI models scored on settled public picks, ranked inside rank_basis, never by profit, with the market's own scores and 95% intervals (tied_with_above: the sample does not separate a row from the one above). No sign-in.
get_privacyWhether the account is private (the default) or public, how many trades are hidden, and whether others see its balance and rank. Only the person makes it public (settings_url).
set_privacyMake the account private: others stop seeing its trades and record. Only call this when the person asked for it in this conversation. It cannot make an account public; the person does that in Settings on the website.
get_positionsOpen positions with stake, instrument_id, bet, payout_if_win_dollars, loss_if_lose_dollars and web_url, plus balance and net worth; start here. live=true (default) adds current_bid_cents (what a market sell pays) and mark_cents (behind unrealized_pnl_dollars). recently_settled: bets settled in the l
get_balanceThe account in paper dollars, carried over; balance_dollars is what is spendable. season_start_dollars is DEPRECATED (start_balance_dollars). web_url is the person's dashboard. recently_settled: bets settled in the last 24 hours; tell the person.
get_historySettled and sold trades, newest first, with realized P&L, instrument_id and a win/loss/void tally; scope with window, since, until or run. A reset write-off is sold, close_reason account_reset.
get_my_statsGrades your closed trades: win rate against prices paid, calibration by price band, closing-line value, return on stake, max drawdown and your stated probability (brier_forecast, log_loss_forecast, brier_stated, log_loss_stated). Default since Sep 1, 2026. by adds a breakdown.
list_marketsBrowse open markets by league, sport or event: compact quote rows with a spread. They go stale: get_market before trading.
search_marketsSubstring search over market and event titles and tickers, one word at a time ('CPI', 'Kansas City': game winners are titled by city). list_markets with event_ticker lists an event.
resolve_marketA bet in words to Arena instrument ids and the Kalshi ticker and side to buy: 'chiefs ml', 'mia +3.5', 'kc mia under 44.5 sunday'. Full-game lines on half points in the NFL, college football, MLB, NHL, NBA and Premier League. It never guesses, so no rows means rephrase: add the other team or league;
get_instrumentOne instrument by id (ins_...) or slug: what YES means, the tie rule, its game, and which side of which Kalshi ticker holds its YES and NO. No sign-in.
get_gameOne game (game_ id, slug or words) with every instrument, moneylines first: instrument_id, ticker, yes_pct (Kalshi's chance; signed out, the moneylines only) and game_state. No sign-in.
list_gamesA day's games in every league, grouped by league, with each moneyline's chance (Kalshi, percent): today (New York) or the date given; an empty day names next_date. A league and no date: its upcoming games, priced. No sign-in.
get_marketLive quote for one market (ticker, ins_ id, slug or a bet in words): each side's bid and ask in cents ($1 contracts), yes_pct, no_pct, spread, status, close, game_state; buy_for_yes and buy_for_no name an instrument's ticker side. contracts or stake_dollars adds cost and payout. Signed out: an instr
get_orderbookDepth as [price_cents, quantity] bid pairs per side plus best bid and ask; contracts adds walk, that size's cost through the book. Paper fills take the whole size at one price.
get_price_historyOne market's recent path in cents (the YES chance in percent): current_cents, open_cents, high_cents, low_cents, change_cents, rv_cents, volume and a sparkline. The *_pts fields are the same numbers under their old names and go in 0.7.0.
screen_marketsScreen open markets by league, group, volume, price, spread, time to close and 24-hour move; rows carry spread_cents and move_cents. get_market before trading.
list_perpsActive Kalshi perpetual tickers and their live settlement marks, in dollars, from GET /perps/markets. status is active (default), inactive, closed or all.
get_perp_markThe live settlement mark for one Kalshi perpetual ticker, in dollars. Tickers come from list_perps.
get_perp_historyRecent stored snapshots for one Kalshi perpetual, newest first, in dollars. limit defaults to 20, max 50. since and until bound the window. source is all, live or backfill. Switched off on Arena's server for now: until it is on, the answer is not_available ("Perp history is not available yet."), whi
get_cross_venue_quotesOne instrument's YES price on each venue Arena shows, always as Kalshi, Novig, Polymarket, ProphetX, not ranked by price: 0-1 chances (yes_pct in percent) with as_of. last_trade_at says when it happened; outcome_last_trades gives each outcome's own last print on Polymarket. Novig's prices arrive ove
find_price_gapsPrice gaps across Kalshi, Novig, Polymarket and ProphetX after taker fees: the list without ref (arbitrage first), all pairs with ref. A pair buys YES on one venue and NO on another; edge = 1 - cost per $1 contract. label is arbitrage only under $1 on contracts that settle alike, reviewed, sized and
get_ordersYour limit orders with instrument_id; default status=resting (live, holding money, able to fill): check it before placing on the same market. cancel_reason says why one ended.
get_track_recordA trader's Ed25519-signed record over the last 90 days (arena.track_record), by user id or name. verify=true checks it against the key Arena publishes on its website; check.ok is true only when every check passes. No sign-in.
place_tradeBuy YES or NO contracts. Required: contracts or stake_dollars; exactly one pair, ticker + side or instrument_id + instrument_side; and, to place (not with dry_run), a fresh UUID idempotency_key and confirm=true. MARKET fills at the ask now. limit_price_cents fills at that price or better or rests (e
sell_tradeExit an open position at the bid (current_bid_cents), or rest a limit exit that holds no money. No bid: a market sell cannot. A closed trade answers its terminal state. route=best may split: fills lists each leg. route=kalshi sells at Kalshi's bid. contract_note on every exit of a non-Kalshi fill. d
cancel_orderWithdraw a resting limit. A buy returns its hold; a sell leaves the position. Already filled or closed answers reduced_by=0. confirm=true. live cancels Kalshi; poly_intl cancels Polymarket International. This server places paper trades only: a call with live or poly_intl is refused (live_not_hosted)
settle_openSettle your positions whose markets have resolved and report what changed; a backstop to the 5-minute settlement cron, safe at session start. Idempotent. Requires confirm=true.