An MCP server for the YNAB API, built with FastMCP.

Tools are generated at startup from YNAB's published OpenAPI spec, so new YNAB endpoints show up without a new release of this package.

1. Install uv.
2. Create a YNAB personal access token at app.ynab.com/settings/developer (New Token). Copy it right away; YNAB only shows it once.
3. Add the server to your MCP client using one of the snippets below, replacing your-token-here with your token.

Every snippet runs uvx ynab-mcp-tools, which downloads the package from PyPI and runs it in an isolated environment. You don't need to clone this repository.

claude mcp add ynab --scope user \
  -e "YNAB_API_TOKEN=your-token-here" \
  -- uvx ynab-mcp-tools

Drop --scope user to add it to the current project only. See the Claude Code MCP docs.

codex mcp add ynab \
  --env "YNAB_API_TOKEN=your-token-here" \
  -- uvx ynab-mcp-tools

Both use the same JSON. Add it to:

• Claude Desktop: ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows)
• Cursor: ~/.cursor/mcp.json (global) or .cursor/mcp.json (project)

{
  "mcpServers": {
    "ynab": {
      "command": "uvx",
      "args": ["ynab-mcp-tools"],
      "env": {
        "YNAB_API_TOKEN": "your-token-here"
      }
    }
  }
}

To find the Claude Desktop config file without typing the path, open Settings → Desktop App → Extensions (Manage) → Local MCP Servers → Edit Config. Finder opens with the file selected. On macOS, right-click it and choose Open With → TextEdit, paste the JSON above, save, then quit and reopen Claude Desktop.

1. Open Settings, search for "MCP", and click MCPs / Plugins.
2. Click Add → Add MCP Server and fill in:
   • Name: YNAB
   • Command to launch: uvx
   • Arguments: ynab-mcp-tools
   • Environment Variables: key YNAB_API_TOKEN, value your-token-here

If a desktop app reports that it can't find uvx, replace uvx with the full path printed by which uvx in a terminal (usually ~/.local/bin/uvx, written out as /Users/<you>/.local/bin/uvx).

Add to ~/.config/opencode/opencode.json:

{
  "mcp": {
    "servers": {
      "ynab": {
        "type": "local",
        "command": ["uvx", "ynab-mcp-tools"],
        "environment": {
          "YNAB_API_TOKEN": "your-token-here"
        }
      }
    }
  }
}

YNAB's API now calls budgets plans, so tools and parameters use that name (getPlans, plan_id). Pass last-used as the plan_id to target your most recently opened plan.

Two kinds of endpoints are left out on purpose:

• getPlanById and getPayees: these return an entire plan export or the full payee list, which is too large for a model's context. The narrower tools above cover the same data.
• Endpoints YNAB marks deprecated, such as importTransactions, which YNAB now accepts but ignores.

YNAB's API has no pagination. The transaction list tools tell the model to pass since_date, until_date, or type, and if a transaction list still comes back over 200,000 characters, the tool returns an error asking the model to retry with a narrower range.

• "Show me my unapproved transactions from the last two weeks."
• "How much have I spent on dining out this month compared to last month?"
• "Categorize my uncategorized transactions, and ask me about anything ambiguous."
• "Move $50 from Vacation to Groceries for this month."

To make your own conventions stick between sessions (how you handle Venmo duplicates, which payees map to which categories), write them into your client's skills or rules, for example a Claude skill.

• Development guide
• YNAB API documentation
• FastMCP documentation

MIT