---
title: "🔑 Authenticate with Key"
description: >-
  Learn how to authenticate with Forkast SDK by signing a message using your
  wallet private key to obtain a valid access token.
---

> **For AI agents:** the complete documentation index is at [llms.txt](/llms.txt). Append `.md` to any page URL for its markdown version.

Authenticates a user by signing a predefined message with their wallet private key. The SDK sends the wallet address, signature, and message to Forkast and returns an **access token** used for authenticated API calls.

```typescript
import { ForkastSDK, Network, LoginResponse } from "@forkastgg/client";

const sdk = new ForkastSDK(Network.MAINNET, "YOUR_API_KEY");
const accountService = sdk.getAccountService();

// Step 1: Load existing Forkast wallet key
const privateKey = getStoredPrivateKey(); // Must have been created manually

if (!privateKey) {
  throw new Error(
    "Forkast wallet not found. Complete sign-up manually on the platform first."
  );
}

// Step 2: Login using Forkast wallet private key
const loginResponse = await accountService.loginWithPrivateKey(privateKey);
const accessToken = loginResponse.accessToken;

console.log("Access Token:", accessToken);
```

**Parameters**

| **Field** | **Type** | **Required** | **Description** |
| --------- | -------- | ------------ | -------------------------- |
| `key`     | string   | Yes          | Private Key of your wallet |

<Info>
  Note:

  1. The user must complete the Forkast wallet sign-up on the Forkast platform. Bots cannot create wallets automatically. 
 2. The private key must be securely stored and accessible for login. Keyless wallets are **not supported** at this time.
 3. Social and Email Login methods are **not allowed** for automation.
  4. A valid Forkast API key must be set in the environment variables.
  5. The `accessToken` returned in `LoginResponse` is required for all authenticated API calls. Store it securely and pass it as the `accessToken` argument when calling protected service methods.
</Info>