Grammarly Install & Auth Skill

Grammarly Install & Auth

Overview

Configure Grammarly API authentication using OAuth 2.0 Bearer tokens. Grammarly provides three main APIs: Writing Score API, AI Detection API, and Plagiarism Detection API. All use the same auth pattern via api.grammarly.com.

Prerequisites

Grammarly Enterprise account with API access
OAuth credentials from Grammarly admin portal
Required scopes: scores-api:read, scores-api:write

Instructions

Step 1: Configure Environment

# .env (NEVER commit)
GRAMMARLY_CLIENT_ID=your_client_id
GRAMMARLY_CLIENT_SECRET=your_client_secret
GRAMMARLY_ACCESS_TOKEN=  # Populated after OAuth

Step 2: Obtain Access Token

// auth.ts
import 'dotenv/config';

async function getAccessToken(): Promise<string> {
  const response = await fetch('https://api.grammarly.com/ecosystem/api/v1/oauth/token', {
    method: 'POST',
    headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
    body: new URLSearchParams({
      grant_type: 'client_credentials',
      client_id: process.env.GRAMMARLY_CLIENT_ID!,
      client_secret: process.env.GRAMMARLY_CLIENT_SECRET!,
    }),
  });
  const { access_token, expires_in } = await response.json();
  console.log(`Token obtained, expires in ${expires_in}s`);
  return access_token;
}

Step 3: Verify Connection

async function verify(token: string) {
  const response = await fetch('https://api.grammarly.com/ecosystem/api/v2/scores', {
    method: 'POST',
    headers: { 'Authorization': `Bearer ${token}`, 'Content-Type': 'application/json' },
    body: JSON.stringify({ text: 'This is a test sentence for verification.' }),
  });
  if (response.ok) console.log('Grammarly API connection verified');
  else console.error('Verification failed:', response.status);
}

Error Handling

| Error | Cause | Solution | |-------|-------|----------| | 401 Unauthorized | Invalid or expired token | Re-authenticate | | 403 Forbidden | Missing API scopes | Check enterprise admin settings | | invalid_client | Wrong credentials | Verify client ID and secret |

Resources

Next Steps

After auth, proceed to grammarly-hello-world.

Agent Skills: Grammarly Install & Auth

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