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Recipe: quantities and shopping list for a catering event

You are catering a breakfast for 60 people. Give Hermes the menu, the portions per person and the pack sizes you buy. It works out how much of everything you need, how many packs to buy and what it all costs.
Time needed 5 minutes
You need A Hermes agent connected to an AI model and a short text with your menu, portions and pack sizes
Result The quantities, a shopping list with the cost of each line and the total, saved in catering-shopping-list.csv

1. Write the menu, the portions and what you buy

Write it like a note to a colleague, in a plain text file: the number of guests, any extra you want for safety, the portions per person, what goes into each item, and the packs you buy with their prices. Upload it in FILES → workspace (see Hermes reads a contract for you). For a small event you can also paste it into the chat.

Our test file, catering-menu.txt:

Event: company breakfast for 60 people, Friday 27 November 2026, 09:30.
Add 10% extra to every quantity for safety (round up).

MENU AND PORTIONS PER PERSON
- Mini ham and cheese sandwiches: 2 per person
- Pasteis de nata: 1 per person
- Mini croissants: 1.5 per person
- Fresh fruit salad: 120 g per person
- Coffee: 2 cups per person
- Orange juice: 200 ml per person

INGREDIENTS PER ITEM
- 1 mini sandwich = 1 mini bread roll + 15 g ham + 15 g cheese
- 1 cup of coffee = 8 g of coffee beans
- Fruit salad: buy 1.5 kg of whole fruit for every 1 kg of fruit salad (peel and waste)

WHAT WE BUY (pack sizes and prices, VAT included)
- Mini bread rolls: bag of 24, 3.60 EUR
- Sliced ham: pack of 500 g, 6.90 EUR
- Sliced cheese: pack of 500 g, 5.40 EUR
- Pasteis de nata: box of 12, 9.00 EUR
- Mini croissants: box of 20, 7.00 EUR
- Mixed whole fruit: 1 kg, 2.20 EUR
- Coffee beans: bag of 1 kg, 18.00 EUR
- Orange juice: bottle of 1 litre, 2.10 EUR

2. Ask for the quantities and the shopping list

In CHAT we wrote:

Open workspace/catering-menu.txt: a company breakfast for 60 people that we are catering. Work out how much of each item we need (including the 10% extra, rounded up), then make the shopping list: how many packs of each thing to buy, the cost of each line and the total cost. Show the maths. Save the shopping list as workspace/catering-shopping-list.csv.

Hermes plans the quantities and the shopping list

  1. The total first: 251.60 EUR, VAT included, and where the file is saved.
  2. The quantities for 60 people with the 10% extra: 132 sandwiches, 66 pasteis de nata, 99 mini croissants, 7.92 kg of fruit salad, 132 cups of coffee and 13.2 litres of juice.
  3. The shopping list: the maths, the number of packs (always rounded up) and the cost of each line.
  4. Hermes explains that it added the 10% only once, and points out that the second bag of coffee is mostly spare: 1 kg makes 125 cups, 5 short of the 132 planned. You decide if 125 cups are enough.

The file catering-shopping-list.csv in FILES → workspace has one line per thing to buy and a total line, ready to print or to paste into an email to your supplier.

Check that it worked

We worked out the whole list ourselves before asking Hermes. Every quantity, every pack count and the total were the same:

To buy We need Packs Cost (EUR)
Mini bread rolls, bag of 24 132 rolls 6 21.60
Sliced ham, 500 g 1,980 g 4 27.60
Sliced cheese, 500 g 1,980 g 4 21.60
Pasteis de nata, box of 12 66 6 54.00
Mini croissants, box of 20 99 5 35.00
Mixed whole fruit, 1 kg 11.88 kg 12 26.40
Coffee beans, 1 kg 1,056 g 2 36.00
Orange juice, 1 litre 13.2 litres 14 29.40
Total 251.60

That is about 4.19 EUR per person. To check your own list, redo one line: guests × portion × 1.1 (for 10% extra), then divide by the pack size and round up.

Make it yours

  • A price for the customer: "Add 2 hours of work for 2 people at 12 EUR an hour and a 40% margin, and tell me the price per person."
  • Another size: "Same menu for 35 people."
  • Dietary needs: "8 guests are vegetarian: give them cheese only."
  • A plan for the day: "Make a timeline for the morning: what to prepare when, if we must be ready at 09:30."
  • Then make a price quote PDF for the customer.

Common problems

The extra was added twice

If you add 10% to the menu items and again to the ingredients, you buy too much. Say where the extra goes, as we did ("Add 10% extra to every quantity" at the top of the file). Hermes said it added it once, on the finished items.

Hermes bought half a pack

Write the pack sizes in the file and ask for "how many packs to buy". Shops do not sell 3.96 packs of ham.

A portion size looks wrong

Hermes uses your portions as they are. It does not know whether 120 g of fruit salad is a lot for your guests. Change the file and ask again.

Next steps