mcp-ynab

FastMCP server that exposes the YNAB API via MCP using YNAB's published OpenAPI spec.

Requirements

• Python 3.12+

• A YNAB personal access token

• uv (recommended) or pip

Configuration

Environment variables:

• YNAB_TOKEN (required): your YNAB API token

• TRANSPORT (optional): http (default) or stdio

Run Locally

Using uv:

uv sync
export YNAB_TOKEN="your_token_here"
export TRANSPORT="http"   # optional, defaults to http
uv run python main.py

HTTP mode starts the server on 0.0.0.0:8080.

Docker

Use the prebuilt image from GHCR:

docker pull ghcr.io/alexfu/mcp-ynab:latest

Run prebuilt image in HTTP mode:

docker run --rm -p 8080:8080 \
  -e YNAB_TOKEN="your_token_here" \
  -e TRANSPORT="http" \
  ghcr.io/alexfu/mcp-ynab:latest

Run prebuilt image in stdio mode:

docker run --rm \
  -e YNAB_TOKEN="your_token_here" \
  -e TRANSPORT="stdio" \
  ghcr.io/alexfu/mcp-ynab:latest

Notes

• The server fetches YNAB's OpenAPI spec at startup from https://api.ynab.com/papi/open_api_spec.yaml.

• Startup will fail if YNAB_TOKEN is missing, TRANSPORT is invalid, or the spec request fails.