Polymarket Sports Arbitrage

Scans sports odds from traditional bookmakers (via The Odds API) to detect arbitrage opportunities — situations where two bookmakers offer contradictory odds on the same match, guaranteeing profit regardless of outcome. Computes implied probabilities, detects arb condition (sum < 1), calculates optimal stake split, and filters only opportunities above 0.5% profit. Source: The Odds API (https://the-odds-api.com), free tier with automatic demo fallback when no key is provided. Saves results to /tmp/sports_arb_results.json. No connection to Polymarket — slug reflects author namespace convention only.

Sports Arbitrage Scanner

A ClawHub automaton skill that continuously monitors sports betting odds from multiple bookmakers, identifies arbitrage opportunities, and reports guaranteed-profit trade setups.

How Arbitrage Works

An arbitrage opportunity exists when the sum of implied probabilities across all outcomes of a match (using the best available odds from any bookmaker) is less than 1.0. This means you can stake proportionally on all outcomes and lock in a profit no matter who wins.

Implied probability of outcome = 1 / decimal_odds Arb exists when: sum(1/odds_i for all outcomes) < 1.0 Profit % = (1 - sum_of_implied_probs) / sum_of_implied_probs * 100 Stake for outcome i = (total_stake / odds_i) / sum_of_implied_probs

Environment Variables

ODDS_API_KEY (optional) API key for The Odds API (https://the-odds-api.com). Free tier allows ~500 requests/month. If not set, the skill falls back to built-in sample/demo data so it can still demonstrate functionality.

MIN_PROFIT_PCT (optional, default: 0.5) Minimum profit percentage to report. Arbs below this threshold are silently filtered out. Increase to reduce noise, decrease to surface more marginal arbs.

TOTAL_STAKE (optional, default: 1000) Hypothetical total stake amount (in your currency) used to compute the concrete stake split per outcome. Purely illustrative — adjust to your bankroll.

SPORTS (optional, default: soccer_epl,basketball_nba,americanfootball_nfl) Comma-separated list of sport keys to scan. Valid sport keys are documented at https://the-odds-api.com/sports-odds-data/sports-apis.html

RESULTS_FILE (optional, default: /tmp/sports_arb_results.json) Path where the JSON results file is written after each scan run.

Output

Each detected arbitrage opportunity is logged to stdout and appended to the JSON results file. The JSON schema per opportunity:

{ "match": "Team A vs Team B", "sport": "soccer_epl", "commence_time": "2026-03-21T15:00:00Z", "profit_pct": 1.23, "total_implied_prob": 0.9879, "outcomes": [ { "name": "Team A", "bookmaker": "pinnacle", "odds": 2.10, "implied_prob": 0.4762, "stake": 476.19, "potential_return": 1000.00 }, ... ], "total_stake": 1000, "guaranteed_return": 1012.30, "detected_at": "2026-03-21T03:00:00Z" }