# Lookup

Turn a human-readable option description into a well-formed OCC option symbol.

## Making Requests

Use `GetLookupAsync` on the `Options` resource.

```csharp
Task<OptionsLookupResponse> GetLookupAsync(
    string userInput,
    MarketDataRequestOptions? options = null, CancellationToken cancellationToken = default)
Task<OptionsLookupResponse> GetLookupAsync(OptionsLookupRequest request, ...)
```

### OptionsLookupRequest

```csharp
new OptionsLookupRequest(string userInput)
```

#### Returns

`OptionsLookupResponse` wrapping a `string` — the OCC option symbol. Read it with `.Values`.

## Examples

```csharp
using MarketDataApp;

using var client = await MarketDataClient.CreateAsync();

var lookup = await client.Options.GetLookupAsync("AAPL 12/17/2027 250 Call");
Console.WriteLine(lookup.Values);   // AAPL271217C00250000
```

For CSV output, call `client.Options.GetLookupCsvAsync(...)` and read `.Csv`. See [Settings](https://www.marketdata.app/docs/sdk/csharp/settings#csv-output).