Use Claude or ChatGPT as a Personal Finance Assistant

MCP (Model Context Protocol) is the open standard AI assistants use to connect to outside tools, and Nethaven runs an MCP server you connect with a single OAuth sign-in, no API keys involved. In practice that means a compatible client can call focused Nethaven tools and answer real questions, turning something like a monthly money review into a conversation instead of a spreadsheet session.

What can you ask the assistant about your Nethaven data?

Once connected, the assistant can request the current data available in Nethaven when the tool runs. Freshness still depends on the latest bank, brokerage, or market-data sync. The same connection that reads your subscriptions or checking account balance can also make small changes when you ask for them:

• “What’s my net worth right now?”
• “What did I earn and spend last month?”
• “Which subscriptions are due soon?”
• “Log a $42 dinner at Nobu.”
• “Set my grocery budget to $600.”

The advantage over a CSV workflow is scope and convenience. The client asks for one defined result when you need it rather than receiving an unrestricted account export. That result is still sent to the connected AI provider, where the provider's privacy and retention policies apply.

What can't the AI assistant do?

This is the part that matters most for a financial app, so it is worth being blunt. The assistant cannot:

• Delete any data
• Link or unlink bank accounts
• Move money
• Make bulk changes
• Access anything outside your own account

Nethaven limits write access to four narrow operations: add one transaction, change one transaction category, set one budget category amount, or create one budget. Your client controls whether it asks for confirmation, so review its tool arguments and approval settings before enabling writes. Revoking access from Settings → Connect MCP stops future calls, but it does not remove results already included in an AI conversation.

What actually happens when you connect an assistant?

There is no API key, no script, and no terminal. The assistant signs in as you, just like a mobile app would:

1. You paste one URL into your assistant’s settings.
2. A login window opens, it is your normal Nethaven sign-in.
3. You approve the connection.
4. The assistant can now answer financial questions using your real data.

How do you connect Nethaven MCP?

1. Confirm that your client and plan support remote MCP with OAuth.
2. Add https://api.nethaven.app/mcp as a remote server or custom app.
3. Complete the Nethaven OAuth sign-in.
4. Review the tool list and your client's approval settings.

Client labels and plan requirements change over time. For the current Claude, ChatGPT, and Cursor paths, see the Connect AI assistant guide or the MCP feature overview.

How is this different from giving an assistant an API key?

Plenty of tools connect to AI assistants through a static API key you generate once and paste into a config file. That key doesn't expire on its own, and if it leaks into a screenshot, a shared repo, or the wrong chat log, whoever has it gets your data until you notice and rotate it. Nethaven's OAuth sign-in gives each client separate access and refresh credentials. Those credentials expire and can be revoked per client, so disconnecting one assistant leaves the others connected.

This is not a Nethaven convention, it is what the protocol requires. The MCP authorization specification builds on OAuth 2.1 and mandates PKCE on the authorization code flow, Protected Resource Metadata (RFC 9728) for server discovery, and Resource Indicators (RFC 8707) so a token is bound to the specific server it was issued for. That last requirement is the one that matters most in practice: a server must reject a token minted for a different service, which is precisely the failure mode a shared API key invites.

Does connecting an AI assistant require Nethaven Pro?

Yes. The AI assistant connection requires an active Nethaven Pro subscription. See pricing for details.