Nyuchi MCP for YNAB connects an AI assistant you already use to your own YNAB budget. The MCP endpoint is https://ynab.nyuchi.com/mcp. There are two ways to connect it, depending on what your client supports.
Option A — Sign in with YNAB (recommended)
In Claude web: Settings → Connectors → Add custom connector.
Paste
https://ynab.nyuchi.com/mcp(no?token=) as the server URL.Under Authentication, leave Always required selected.
Under OAuth client, pick No client ID — register one automatically. This server supports Dynamic Client Registration, not Anthropic's hosted client metadata option listed above it — picking that one instead produces a "Couldn't determine the server settings" error.
Click Add, then Connect — you'll land on YNAB's own sign-in page to authorize access, then bounce back connected. No token ever touches this site.
Before that, your client shows a permissions screen listing exactly what this connector can read (plans, accounts, categories, payees, payee locations, months, and transactions) and what it can write or change (accounts, categories, payees, and transactions) — review it there before continuing.
Option B — Your own personal access token
For clients without a full OAuth UI, or if you'd rather not use OAuth: get a YNAB personal access token, then use the MCP endpoint with ?token=<your-YNAB-token> appended. Clients that support custom headers can send Authorization: Bearer <your-YNAB-token> instead.
Your token is used only to make YNAB API calls on your behalf, per request. Nobody else's budget is visible to you, and yours isn't visible to them.
Getting an error on the redirect back from YNAB?
An "expired or unknown authorization session" error right after signing in with YNAB is almost always momentary — just start the connection again from your client. If it happens more than once in a row, let us know via the chat bubble or email below.
Still stuck?
Use the chat bubble in the corner of ynab.nyuchi.com, or email [email protected].