Betting Analysis

Quick Start

sports-skills betting convert_odds

--odds

=

-150

--from_format

=

american

sports-skills betting devig

--odds

=

-150,+130

--format

=

american

sports-skills betting find_edge

--fair_prob

=

0.58

--market_prob

=

0.52

sports-skills betting evaluate_bet

--book_odds

=

-150,+130

--market_prob

=

0.52

sports-skills betting find_arbitrage

--market_probs

=

0.48

,0.49

sports-skills betting parlay_analysis

--legs

=

0.58

,0.62,0.55

--parlay_odds

=

600

sports-skills betting line_movement

--open_odds

=

-140

--close_odds

=

-160

Python SDK:

from

sports_skills

import

betting

betting

.

convert_odds

(

odds

=

-

150

,

from_format

=

"american"

)

betting

.

devig

(

odds

=

"-150,+130"

,

format

=

"american"

)

betting

.

find_edge

(

fair_prob

=

0.58

,

market_prob

=

0.52

)

betting

.

find_arbitrage

(

market_probs

=

"0.48,0.49"

)

betting

.

parlay_analysis

(

legs

=

"0.58,0.62,0.55"

,

parlay_odds

=

600

)

betting

.

line_movement

(

open_odds

=

-

140

,

close_odds

=

-

160

)

Odds Formats

Format

Example

Description

American

-150

,

+130

US sportsbook standard. Negative = favorite, positive = underdog

Decimal

1.67

,

2.30

European standard. Payout per $1 (includes stake)

Probability

0.60

,

0.43

Direct implied probability (0-1). Polymarket uses this format

Conversion rules:

American negative: prob = -odds / (-odds + 100). Example: -150 → 150/250 = 0.600

American positive: prob = 100 / (odds + 100). Example: +130 → 100/230 = 0.435

Decimal: prob = 1 / odds. Example: 1.67 → 0.599

Kalshi prices (0-100 integer): divide by 100 to get probability format

Commands

Command

Required

Optional

Description

convert_odds

odds, from_format

Convert between American, decimal, probability

devig

odds

format

Remove vig from sportsbook odds → fair probabilities

find_edge

fair_prob, market_prob

Compute edge, EV, and Kelly from two probabilities

kelly_criterion

fair_prob, market_prob

Kelly fraction for optimal bet sizing

evaluate_bet

book_odds, market_prob

book_format, outcome

Full pipeline: devig → edge → Kelly

find_arbitrage

market_probs

labels

Detect arbitrage across outcomes from multiple sources

parlay_analysis

legs, parlay_odds

odds_format, correlation

Multi-leg parlay EV and Kelly analysis

line_movement

open_odds, close_odds, open_line, close_line, market_type

Analyze open-to-close line movement

Workflows

Workflow: Compare ESPN vs Polymarket/Kalshi

This is the primary workflow. The agent already has odds from ESPN and a prediction market — no user estimation needed.

Get ESPN moneyline odds for a game (e.g., from

nba get_scoreboard

):

Home:

-150

, Away:

+130

Get Polymarket/Kalshi price for the same outcome (e.g., home team at

0.52

).

De-vig the ESPN odds to get fair probabilities:

devig --odds=-150,+130 --format=american

→ Fair: Home 57.9%, Away 42.1% (removed ~3.5% vig)

Compare fair prob to market price:

find_edge --fair_prob=0.579 --market_prob=0.52

→ Edge: 5.9%, EV: 11.3%, Kelly: 0.123

Or do it all in one step:

evaluate_bet --book_odds=-150,+130 --market_prob=0.52

Workflow: Arbitrage Detection

Spot guaranteed-profit opportunities when prices across sources don't sum to 100%.

Get the best available price per outcome from different sources:

Source A (Polymarket): Home team at 0.48

Source B (Kalshi): Away team at 0.49

find_arbitrage --market_probs=0.48,0.49 --labels=home,away

→ Total implied: 0.97 (< 1.0 = arbitrage!)

→ Guaranteed ROI: 3.09%

→ Allocation: 49.5% on home, 50.5% on away

For 3-way football markets:

find_arbitrage --market_probs=0.40,0.25,0.30 --labels=home,draw,away

Workflow: Parlay Evaluation

Evaluate multi-leg parlays to see if the offered odds are +EV.

De-vig each leg to get fair probabilities:

Leg 1:

devig --odds=-150,+130

→ fair prob 0.58

Leg 2:

devig --odds=-130,+110

→ fair prob 0.55

Leg 3:

devig --odds=-110,-110

→ fair prob 0.50

parlay_analysis --legs=0.58,0.55,0.50 --parlay_odds=600

→ Combined fair: 15.95%, offered +600 implies 14.29%

→ Edge: 1.66%, +EV

If legs are correlated (e.g. same-game parlay): add

--correlation=0.1

— this increases combined probability since correlated events are more likely to co-occur

Workflow: Line Movement from ESPN

Quantify how a line has moved and what it implies about sharp money.

Get ESPN odds for a game — both open and close lines are available:

Open moneyline: -140, Close moneyline: -160

Open spread: -6.5, Close spread: -7.5

line_movement --open_odds=-140 --close_odds=-160

→ Probability shift: +3.21% toward favorite

→ Classification: sharp_action

With spread too:

line_movement --open_odds=-140 --close_odds=-160 --open_line=-6.5 --close_line=-7.5

→ If ML and spread move same direction: sharp action confirmed

→ If they move opposite: reverse line movement (public vs sharp split)

Workflow: De-Vig Sportsbook Odds

Strip the vig/juice from DraftKings odds to see the "true" implied probabilities.

devig --odds=-110,-110 --format=american

→ Each side is 50.0% fair (standard -110/-110 spread/total)

devig --odds=-200,+170 --format=american

→ Favorite: 65.2%, Underdog: 34.8%

devig --odds=-150,+300,+400 --format=american

(3-way football)

→ Home: 47.3%, Draw: 19.8%, Away: 15.7%

Workflow: Odds Conversion

Convert odds from one format to another.

convert_odds --odds=-150 --from_format=american

→ Probability: 60.0%, Decimal: 1.6667

convert_odds --odds=2.50 --from_format=decimal

→ Probability: 40.0%, American: +150

Examples

User: "Is there edge on the Lakers game? ESPN has them at -150 and Polymarket has them at 52 cents"

devig --odds=-150,+130 --format=american

→ Fair home prob ~58%

find_edge --fair_prob=0.58 --market_prob=0.52

→ Edge ~6%, positive EV

kelly_criterion --fair_prob=0.58 --market_prob=0.52

→ Kelly fraction

Present: edge, EV per dollar, recommended bet size as % of bankroll

User: "Can I arb this? Polymarket has home at 48 cents and Kalshi has away at 49 cents"

find_arbitrage --market_probs=0.48,0.49 --labels=home,away

If arbitrage_found: present allocation percentages and guaranteed ROI

If not: present the overround and explain there's no guaranteed profit

User: "Is this 3-leg parlay at +600 worth it?"

De-vig each leg to get fair probs (e.g. 0.58, 0.62, 0.55)

parlay_analysis --legs=0.58,0.62,0.55 --parlay_odds=600

Present: combined fair prob, edge, EV, +EV or -EV, Kelly fraction

User: "The line moved from -140 to -160, what does that mean?"

line_movement --open_odds=-140 --close_odds=-160

Present: probability shift, direction, magnitude, classification (sharp action, steam move, etc.)

User: "What are the true odds for this spread? Both sides are -110"

devig --odds=-110,-110 --format=american

Present: each side is 50% fair probability, vig is ~4.5%

User: "Convert -200 to implied probability"

convert_odds --odds=-200 --from_format=american

Present: 66.7% implied probability, 1.50 decimal odds

Commands that DO NOT exist — never call these

get_odds

— does not exist. This module analyzes odds, it doesn't fetch them. Use nba-data/nfl-data/etc. for ESPN odds, or polymarket/kalshi for prediction market prices.

calculate_ev

— does not exist. Use

find_edge

or

evaluate_bet

instead.

compare_markets

— does not exist. Use the

markets

skill for cross-platform comparison.

If a command is not listed in the Commands section above, it does not exist.

Key Concepts

Vig/Juice

The sportsbook's margin. A -110/-110 line implies 52.4% + 52.4% = 104.8% total, meaning 4.8% overround. De-vigging removes this to get fair probabilities.

Edge

The difference between your estimated true probability and the market price. Positive edge = profitable in expectation.

Kelly Criterion

Optimal bet sizing that maximizes long-term growth. f* = (fair_prob - market_prob) / (1 - market_prob). For conservative sizing, multiply the Kelly fraction by 0.5 (half-Kelly) or 0.25 (quarter-Kelly).

Expected Value (EV)

Average return per dollar bet. EV = fair_prob / market_prob - 1.

Arbitrage

When prices across sources don't sum to 100%, you can bet all outcomes and guarantee profit regardless of the result.

Parlay

A multi-leg bet where all legs must win. Combined probability = product of individual leg probabilities. Higher risk, higher reward. Check if the offered odds exceed the fair combined odds.

Line Movement

How odds change between open and close. Large moves toward one side suggest sharp/professional money. Reverse line movement (moneyline and spread moving opposite directions) suggests a public vs sharp split.