Store Price Tracker in ChatGPT

Questions it answers

Ask what an online store sells, what it charges and what changed since the last time anyone looked.

Ask "track competitor prices on allbirds.com", "what did gymshark.com change this week?", "which products on this store are sold out?" or "how has the price of this hoodie moved?".

Store Price Tracker reads the public product feed that Shopify stores publish at /products.json, the same list any visitor's browser can fetch without logging in.

It reports products, prices, variants and availability, and compares each daily snapshot with the one before it: new products, removed products, price changes and stock changes, per variant.

A store you ask about is added to a daily snapshot list, so its price history grows over time and can be read back for any product.

It checks the store's robots.txt first, identifies itself with a clear User-Agent, pauses between requests and backs off when a store asks for fewer.

When comparing stores across borders quoting in different currencies, it normalizes prices using daily foreign exchange reference rates of the European Central Bank (ECB, https://www.ecb.europa.eu), read through the keyless Frankfurter API (https://frankfurter.dev; URL: https://api.frankfurter.dev/v2/providers/ecb/rates; checked 2026-10-02). Data is reused under the ECB Conditions for Reuse of Public Sector Information with attribution.

Stores that are not on Shopify, or that keep their feed private, are reported as unavailable.

It stores only public product data (titles, prices, variants, availability) and the store's address.

Nothing about you is kept: no prompts, no account and no IP address, only a daily count of calls per tool.

Short questions this server answers, each with a direct answer: Track an online store's prices and stock changes.

What it can do

• Lists the products, prices, variants and availability of a Shopify store
• Shows new products, removed products, price changes and stock changes since the previous daily snapshot
• Keeps a daily snapshot of every store it is asked about, so price history builds up
• Reads the price and availability history of one product
• Compares up to five stores in one answer
• Compares store catalogs for price gaps, currency differences, and landed margins

Tools

• check_store_prices, Check a store's products and price changes. Read an online store's products, prices and availability, and what changed since its previous daily snapshot. Use it for questions like "track competitor prices on allbirds.com", "what did gymshark.com change?", "what is new or sold out at this store?". Pass store addresses, up to 5: a bare host such as "allbirds.com", an https link to any page of the store, or a myshopify.com address. Works only for Shopify stores that publish their public product feed (/products.json). Calling it adds the store to a daily snapshot list, so its history builds up. Optional: query (text in a product's title, brand, type or handle), limit. Returns per store a status, the snapshot date, product count, currency, change counts and lists of new, removed, repriced and restocked or sold-out variants, plus matching products. The first snapshot has no changes. Not for one product's history (use get_product_price_history) or for comparing two stores (use compare_store_prices).
• get_product_price_history, Get a product's price history. Read how one product's price and availability moved over the days a store has been tracked. Use it for questions like "how has the price of this hoodie changed?", "when did this product go on sale?", "has this been out of stock?". It is most useful after check_store_prices has tracked the store: history starts on the first snapshot, so a store never read before has one day only. Calling it reads the store when there is no snapshot for today and adds it to the daily snapshot list. Pass the store's address and the product's link, handle or title; an exact handle or title wins over part of a title. Returns per variant the price, the compare-at (was) price and availability on each day something changed. Status ambiguous returns candidates: ask the user to pick one, then call again with that title. Not for a whole store's changes (use check_store_prices) or for comparing stores (use compare_store_prices).
• compare_store_prices, Compare prices and find gaps across stores. Compare product prices between two online stores to find price gaps and margin differences. Use it for questions like "compare prices between allbirds.com and allbirds.co.uk" or "which store sells this item cheaper?". Pass source_store (the benchmark) and target_store addresses. Products are paired by title by default; use match_by "handle" for two regional stores of one brand. Other currencies are converted into the target currency with the latest ECB reference rate unless fx_rate is given. Returns matched pairs with both prices, the gap and percent spread (positive when the target store is dearer), stock, links and the landed gap: the gap left after the shipping and duty allowances per item. Status no_matches means no product paired: try another match_by, a shorter query or a lower min_gap_pct. It adds both stores to the daily snapshot list. Not for one store's changes (use check_store_prices) or one product's history (use get_product_price_history).

Add Store Price Tracker in ChatGPT

ChatGPT does not read a local config file. A custom MCP server is added in the product, and only after developer mode is on. These steps were checked against OpenAI's plugin connect guide and the ChatGPT MCP guide on 2026-10-01. Developer mode can be hidden by a workspace policy, so a Team or Enterprise admin may have to allow it first.

1. Open ChatGPT settings, then Security and login, and turn on Developer mode.
2. Open ChatGPT plugins and select the plus button.
3. Enter a name such as "Store Price Tracker" and a one-line description of what you want it to answer.
4. Under Connection, choose the public endpoint and paste this URL. Include the /mcp path. Do not add a tunnel id: this server is already public.

   https://stores.openkrill.app/mcp

5. Create the connection and review the tools ChatGPT lists. You should see check_store_prices, get_product_price_history, compare_store_prices. The feedback tools on the same server are optional and not required for the lookup.
6. Start a new conversation, add the connection from the tools menu, and ask: Track competitor prices on allbirds.com

No API key and no OAuth client id are required. The server answers without a login. Calls are limited per network and per day, and a limit comes back as a tool error rather than a partial answer. If the tool list is stale after a server change, open the connection and select Refresh, then start a new conversation.

The ChatGPT desktop app, Codex CLI and IDE extension share a different config. In the desktop app, open Settings, then MCP servers, choose Add server, select Streamable HTTP, and paste the same URL. In ~/.codex/config.toml the equivalent is a table named mcp_servers.store-prices with url = "https://stores.openkrill.app/mcp". ChatGPT on the web does not read that file. A published directory listing is also a different path: this page is the developer-mode connection, not a claim that Store Price Tracker is already in the ChatGPT directory.

Treat the server as untrusted until you have read a few answers. A remote MCP server sees the arguments the model sends. Store Price Tracker is read-only and documents what it sends onward on the privacy page.

If it does not work

A call checked on 2026-10-17

allbirds.com is a public Shopify store used in the plugin's own starter prompts. The request below was posted to https://stores.openkrill.app/mcp as tools/call. HTTP 200. Source: the Store Price Tracker server, read 2026-10-17.

{
  "method": "tools/call",
  "params": {
    "name": "check_store_prices",
    "arguments": {
      "stores": [
        "allbirds.com"
      ],
      "limit": 2
    }
  }
}

• stores. 1 returned
• stores status. stale

Repeat the call yourself if you need a newer reading. Cached answers expire. A rate limit is not a result: wait and try again. Nothing in the call is a ranking, a filing, or advice.

Using it in production

Nothing to install and nothing to run: no package, no Python or Node.js version and no environment variable. Store Price Tracker runs on our servers, and your client only needs the URL https://stores.openkrill.app/mcp.

Use it in other apps

• Store Price Tracker in Claude
• Store Price Tracker in Cursor
• Store Price Tracker in VS Code
• Store Price Tracker in Pi

Roles that use Store Price Tracker

• Shopify operator guide

Frequently asked questions

Words on this page

• MCP (Model Context Protocol) definition
• Streamable HTTP transport definition
• Tool primitive definition
• Rate limit policy definition

Source: plugin listing for store-prices in this repository, and a live tools/call on 2026-10-17. As of 2026-10-17.