Add Vextir to your assistant

Vextir connects to your assistant over the Model Context Protocol. The first time your assistant opens your diary, it asks you to sign in.

Claude (web, desktop, mobile)

1. Open Customize → Connectors, click +, then Add custom connector.
2. Paste the server URL and click Add. Leave the OAuth fields empty.
3. The first time Claude opens your diary, click Connect and sign in with your email.

Claude Code

claude mcp add --transport http vextir https://mcp.vextir.com/mcp

ChatGPT

1. Enable Developer mode in Settings → Security and login (Plus, Pro, Business, Enterprise or Edu, on the web).
2. Create a developer-mode app with the + button, paste the server URL and choose Mixed Authentication.
3. When ChatGPT first opens your diary, it asks you to link your Vextir account.

What your assistant can do

• diary_guide: reads how your diary is set up, plus a short summary, at the start of a conversation.
• diary_write: records what you tell it, and corrects entries as new versions.
• diary_query: answers questions from your record, including how it looked at any earlier moment.
• diary_run: runs small programs over your diary for bulk changes and analysis, in a sandbox with no internet access.

Building your own app

Vextir runs a standard OAuth 2.1 authorization server at https://mcp.vextir.com (metadata at /.well-known/oauth-authorization-server), and accepts every way an MCP client can identify itself: Client ID Metadata Documents, dynamic client registration, and pre-registered clients. Most apps need no setup. If yours needs a fixed client ID and secret, create one at mcp.vextir.com/clients. PKCE (S256) is required, and the scope is diary.

Signing in

Sign-in uses a 6-digit code sent to your email, and creates your account the first time. You'll see which app is asking before you allow access. If you already used CarbSum, it's the same account and the same diary.