> For the complete documentation index, see [llms.txt](https://timechain.gitbook.io/neucron-javascript-sdk/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://timechain.gitbook.io/neucron-javascript-sdk/identity-and-access/oauth-sign-in-with-neucron.md).

# OAuth / Sign in with Neucron

Accessor: `sdk.oauth`

Build Sign in with Neucron using OAuth 2.0 authorization, token exchange, client metadata, and callback handling.

## Method surface

| Method                       | Purpose        |
| ---------------------------- | -------------- |
| `sdk.oauth.authorize()`      | authorize      |
| `sdk.oauth.exchangeToken()`  | exchangeToken  |
| `sdk.oauth.clientInfo()`     | clientInfo     |
| `sdk.oauth.handleCallback()` | handleCallback |

## Basic usage

```typescript
import NeucronSDK from '@timechainlabs/neucron-ts-sdk';

const sdk = new NeucronSDK({ authToken: process.env.NEUCRON_TOKEN });

// Use sdk.oauth methods after authentication.
```

## Notes

* Methods return `Promise<HttpResponse<T>>` unless they are local helpers such as token getters/setters.
* Authenticate with `sdk.auth.login()` or initialize with `authToken` before protected calls.
* Pass `businessId` on business-scoped operations; constructor-level `businessId` is typed but not applied globally.
* Request and response schemas are exported from `@timechainlabs/neucron-ts-sdk` and `@timechainlabs/neucron-ts-sdk/schemas`.