> ## Documentation Index
> Fetch the complete documentation index at: https://api.unusualwhales.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

> ## Agent Instructions
> API requests use the base URL https://api.unusualwhales.com and require a bearer token in the `Authorization` header (`Authorization: Bearer <API_KEY>`). Create and manage API tokens at https://unusualwhales.com/dashboard/api.
> For live market data inside an AI tool, use the Unusual Whales MCP server at https://unusualwhales.com/public-api/mcp.
> Instructions for agents using Unusual Whales tools: https://unusualwhales.com/skill.md

# OptionChain

> An option contract with all its meta data.

Message
fields**9**
used by[FlexConsolidation](/docs/kafka/types/FlexConsolidation.md)

**Proto definition**

```protobuf schema.proto theme={null}
message OptionChain {
  int32 id = 1;
  string option_symbol = 2;
  int32 strike = 3;
  Ticker ticker = 4;
  string expiry = 5;
  OptionType type = 6;
  Ticker root_ticker = 7;
  bool first_time_options_today = 8;
  bool created_today = 9;
}
```

## Fields

The number on the right of each row is the protobuf field number.

id
int32
1

Unique id of the option contract.

option\_symbol
string
2

OSI option symbol, e.g. AAPL260116C00150000.

strike
int32
3

Strike price in thousandths of a dollar.

ticker
[Ticker](/docs/kafka/types/Ticker.md)
4

Underlying ticker of the contract (e.g. SPXW, not the root SPX).

expiry
string
5

Expiration date in YYYY-MM-DD.

type
[OptionType](/docs/kafka/types/OptionType.md)
6

Call or put.

root\_ticker
[Ticker](/docs/kafka/types/Ticker.md)
7

Root ticker of the contract (equals ticker for stocks, parent index for index options).

first\_time\_options\_today
bool
8

True when options appear for this ticker for the first time, i.e. it had no other active (non-expired) chains loaded when this chain was created.

created\_today
bool
9

True when this contract was newly created (it did not exist before).