# LibraryPineStudy [Integration guide](https://docs.lumencharts.com/charting-library/reference/compatibility) · [Reference index](https://docs.lumencharts.com/charting-library/api/) Public contract reference. This declaration describes types and callback shapes; availability is constrained by the linked integration guide and the runtime capability. Legacy product-specific fields are not a promise of implementation. ## init {#init} ```ts init?( ctx: IContext, inputs: (index: number) => T, ): void; ``` Use the type signature above and the integration guide for the owning capability. | Parameter | Type | Required | | --- | --- | --- | | `ctx` | `IContext` | Yes | | `inputs` | `(index: number) => T` | Yes | ## main {#main} ```ts main( ctx: IContext, inputs: (index: number) => T, ): TPineStudyResult | null; ``` Use the type signature above and the integration guide for the owning capability. | Parameter | Type | Required | | --- | --- | --- | | `ctx` | `IContext` | Yes | | `inputs` | `(index: number) => T` | Yes | ## signature {#signature} ```ts [key: string]: any; ``` Use the type signature above and the integration guide for the owning capability. | Parameter | Type | Required | | --- | --- | --- | | `key` | `string` | Yes | ## Related types - [IContext](https://docs.lumencharts.com/charting-library/api/IContext) - [StudyInputValue](https://docs.lumencharts.com/charting-library/api/StudyInputValue) --- Documentation page: https://docs.lumencharts.com/charting-library/api/LibraryPineStudy