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Overview

The OptionLeg model represents a single position (leg) within an options strategy. Each leg can be a call option, put option, or stock position, and can be either bought or sold. Legs are combined in the StrategyState model to create complex multi-leg strategies like spreads, condors, straddles, and more.

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Model Structure

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type
string
required
Type of the position. Must be one of: "call", "put", or "stock"
  • call - Call option (right to buy at strike)
  • put - Put option (right to sell at strike)
  • stock - Underlying stock position
Pattern: ^(call|put|stock)$
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action
string
required
Whether you are buying or selling this position. Must be one of: "buy" or "sell"
  • buy - Long position (you pay premium for options)
  • sell - Short position (you receive premium for options)
Pattern: ^(buy|sell)$
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strike
float
required
Strike price of the option (or entry price for stock). Must be greater than 0.For options, this is the exercise price. For stock, this represents the purchase/sale price.Example: 150.00 for a $150 strike call
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expiration
date
required
Expiration date of the option in ISO 8601 format (YYYY-MM-DD).For stock positions, this can be set to a far future date since stock doesn’t expire.Example: "2026-04-17" for April 17, 2026 expiration
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qty
integer
required
Number of contracts (for options) or shares (for stock). Must be greater than 0.Important: For options, 1 contract = 100 shares of the underlying asset.Examples:
  • 1 - One option contract (controls 100 shares)
  • 5 - Five option contracts (controls 500 shares)
  • 100 - For stock, 100 shares
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premium
float
default:"0.0"
Premium paid (for buy) or received (for sell) per contract/share. Must be non-negative.For options, this is the option price. For stocks, it can represent dividends or be left at 0.Examples:
  • 3.50 - 3.50premiumpershare(3.50 premium per share (350 total for 1 contract)
  • 0.0 - No premium data or stock position
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volume
integer
default:"0"
Trading volume of the option contract. Used for liquidity analysis.Higher volume generally indicates better liquidity and tighter bid-ask spreads.
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open_interest
integer
default:"0"
Open interest for the option contract. Indicates the number of outstanding contracts.Higher open interest suggests more active trading and better price discovery.

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Example Positions

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Long Call Option

{
  "type": "call",
  "action": "buy",
  "strike": 155.0,
  "expiration": "2026-04-17",
  "qty": 1,
  "premium": 3.50,
  "volume": 1250,
  "open_interest": 8420
}
This represents:
  • Buying 1 call option contract
  • Strike price of $155
  • Expires April 17, 2026
  • Paid 3.50pershare(3.50 per share (350 total)
  • High liquidity (good volume and open interest)

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Short Put Option

{
  "type": "put",
  "action": "sell",
  "strike": 145.0,
  "expiration": "2026-04-17",
  "qty": 2,
  "premium": 4.20,
  "volume": 890,
  "open_interest": 3210
}
This represents:
  • Selling 2 put option contracts
  • Strike price of $145
  • Expires April 17, 2026
  • Received 4.20pershare(4.20 per share (840 total for 2 contracts)
  • Moderate liquidity

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Stock Position

{
  "type": "stock",
  "action": "buy",
  "strike": 150.50,
  "expiration": "2030-12-31",
  "qty": 100,
  "premium": 0.0
}
This represents:
  • Buying 100 shares of stock
  • At $150.50 per share
  • Far future expiration (stock doesn’t expire)
  • No premium (stock purchase, not option)

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Common Strategy Examples

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Bull Call Spread

{
  "legs": [
    {
      "type": "call",
      "action": "buy",
      "strike": 150.0,
      "expiration": "2026-04-17",
      "qty": 1,
      "premium": 5.00
    },
    {
      "type": "call",
      "action": "sell",
      "strike": 155.0,
      "expiration": "2026-04-17",
      "qty": 1,
      "premium": 2.50
    }
  ]
}

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Protective Put

{
  "legs": [
    {
      "type": "stock",
      "action": "buy",
      "strike": 150.0,
      "expiration": "2030-12-31",
      "qty": 100,
      "premium": 0.0
    },
    {
      "type": "put",
      "action": "buy",
      "strike": 145.0,
      "expiration": "2026-04-17",
      "qty": 1,
      "premium": 3.00
    }
  ]
}

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Iron Condor (4 legs)

{
  "legs": [
    {
      "type": "put",
      "action": "buy",
      "strike": 140.0,
      "expiration": "2026-04-17",
      "qty": 1,
      "premium": 2.50
    },
    {
      "type": "put",
      "action": "sell",
      "strike": 145.0,
      "expiration": "2026-04-17",
      "qty": 1,
      "premium": 4.20
    },
    {
      "type": "call",
      "action": "sell",
      "strike": 155.0,
      "expiration": "2026-04-17",
      "qty": 1,
      "premium": 4.10
    },
    {
      "type": "call",
      "action": "buy",
      "strike": 160.0,
      "expiration": "2026-04-17",
      "qty": 1,
      "premium": 2.40
    }
  ]
}

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Field Validation

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type
string
✅ Must be exactly: "call", "put", or "stock"❌ Case-sensitive - "Call" or "CALL" will be rejected
​
action
string
✅ Must be exactly: "buy" or "sell"❌ Case-sensitive - "Buy" or "SELL" will be rejected
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strike
float
✅ Must be greater than 0❌ Negative or zero values will be rejected
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expiration
date
✅ Must be in ISO 8601 format: YYYY-MM-DD❌ Invalid date formats will be rejectedValid: "2026-04-17"Invalid: "04/17/2026", "2026-4-17"
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qty
integer
✅ Must be greater than 0❌ Negative or zero quantities will be rejected
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premium
float
✅ Must be non-negative (>= 0)❌ Negative premiums will be rejected

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Understanding Contract Multiplier

When calculating position value:
  • Options: Value = qty × premium × 100
  • Stock: Value = qty × strike

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Example Calculations:

Long Call:
  • qty = 1, premium = 3.50
  • Cost = 1 × 3.50 × 100 = $350
Short Put:
  • qty = 2, premium = 4.20
  • Credit = 2 × 4.20 × 100 = $840
Stock Position:
  • qty = 100, strike = 150.50
  • Cost = 100 × 150.50 = $15,050
  • StrategyState - Complete strategy configuration
  • Greeks - Risk metrics calculated from option legs

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