Australian grocery prices, for your AI ShopSaver
Ask your AI what the groceries cost. It checks Coles, Woolworths and ALDI — and tells you when it can’t be sure.
- Free
- Read-only
- No account
- Refreshed nightly
What it is
No app to install and nothing to sign up for. ShopSaver is a remote MCP server: you add one address to Claude, ChatGPT or any MCP client, then ask about groceries in plain English.
-
1
You ask. “Where’s Vegemite cheapest this week?”
-
2
Your AI calls ShopSaver. It reads prices from Coles, Woolworths and ALDI, refreshed every night.
-
3
Old prices are re-checked. If what’s stored is more than a day old, it fetches the shelf price live before answering.
Four things you can ask
-
i.
“Who has the cheapest olive oil right now?”
Finds a product across all three chains, cheapest first by comparable unit price, so a 750 ml bottle and a 1 L bottle are ranked fairly.
search_products -
ii.
“Has this coffee gone up lately?”
Shows how one product’s price has moved over time, from the price history ShopSaver keeps.
get_price_history -
iii.
“Would my weekly shop be cheaper at ALDI?”
Prices a whole shopping list against another chain, line by line, and reports how much of the list it could actually compare.
compare_basket -
iv.
“Is it worth waiting for this to go on special?”
Gives a probability, week by week, that a product goes on special. It models Australian catalogue weeks, which run Wednesday to Tuesday.
predict_price
The fine print, in large type
A price comparison is only useful if it’s honest about what it doesn’t know. ShopSaver would rather give no answer than a wrong one.
- Nothing stale passes as current.
- A price older than 24 hours is never served as today’s. ShopSaver fetches it again, or tells your AI it couldn’t.
- No verdict on thin evidence.
- If too few lines of a basket could be matched — under half, by default — it won’t name a cheaper chain. You still get the numbers it does have.
- Same quantity, or no comparison.
- Two packs are compared only when they’re shown to hold the same amount. Anything it can’t verify is set aside and counted, never quietly dropped.
- Odds, not promises.
- Specials are forecast as probabilities. Tested forward from 15 catalogue Wednesdays on products that cycle on and off special, it called each day’s promo-or-regular state correctly 78% of the time, against 70% for assuming specials simply alternate. A chain’s choice to skip a promo week is the part no history predicts.
Add it to your AI
On claude.ai or the Claude desktop app.
Add ShopSaver from the Claude directory
Or add it by hand as a custom connector:
- Open Settings → Connectors.
- Choose Add custom connector.
- Name it ShopSaver and paste
the server URL. - In a new chat, ask about a grocery price.
Free plans may be limited to one custom connector.
In ChatGPT on the web.
- Open Settings → Apps & Connectors → Advanced and turn on Developer mode.
- Create a connector named ShopSaver.
- Paste
the server URLas its MCP server URL.
Custom connectors are available on paid ChatGPT plans.
One command in your terminal.
claude mcp add --transport http shopsaver <URL>Add to .vscode/mcp.json in your workspace.
{"servers":{"shopsaver":{"type":"http","url":"<URL>"}}}Cursor reads ~/.cursor/mcp.json; most other MCP clients take the same shape.
{"mcpServers":{"shopsaver":{"url":"<URL>"}}}Beta ShopSaver is new and still finding its feet. A wrong price, a product it can’t find, or an idea: tell us →
Questions at the counter
- Which is cheapest: Coles, Woolworths or ALDI?
- It depends on what’s in your trolley. ShopSaver doesn’t publish a league table. It prices your own list line by line against another chain, and names a cheaper chain only when enough of the list could be compared — at least half, by default.
- Is ShopSaver free? Do I need an account?
- It’s free and read-only. There’s no app to install and no account to create: you add one server address to your AI assistant.
- How current are the prices?
- Prices are refreshed every night. If a price is more than a day old when you ask, ShopSaver fetches it fresh before answering, or tells your AI it couldn’t.
- Can it tell me when something will go on special?
- It gives a probability, week by week, that a product goes on special, worked out from that product’s price history over Australian catalogue weeks (Wednesday to Tuesday). They are odds, not promises. If there isn’t enough history yet, it says so instead of guessing.
- Which AI assistants can use it?
- Claude (as a custom connector), ChatGPT (as a connector in developer mode, on paid plans), Claude Code, VS Code, Cursor, and other MCP clients that can connect to a remote server over HTTP.
- What is an MCP server?
- MCP, the Model Context Protocol, is an open standard that lets AI assistants call outside tools. ShopSaver is one of those tools: your AI sends it a grocery question and gets prices back.