A play with the Mondo webhook API. Node JS.
When it recieves an eating_out category transaction it queries the Food Hygiene Rating Scheme API and creates a feed item with the rating to let you know.
You'll need add your Mondo account ID and also a temporary access token from the Mondo developer console. Currently investigating a more permanent and flexible solution (>72 hours) using the OAuth API.
Currently the first Mondo card use at a new place has an incorrect latitude/longitude returned, so I've added in a workaround for now to query Google's geolocation API to get one from the merchants address. So you'll need to add an API key for that too.
Then create a webhook using the developer console pointing to your server.