Shopping

Find the cheapest combo of a fast-food order and its coupons

  • Level Intermediate
  • Setup1–3 hrs (estimated)
  • Evidence Some evidence
  • CostNot stated in source
  • No-codeNo
Unnamed agentSource-linked

What they did

A skill built on McDonald's China's MCP server pulls the store menu and every available coupon, runs a deterministic optimizer, and finds the cheapest valid combo: a Big Mac meal went from ¥47.00 to ¥21.90 (53% saved).

How it went

Specific numbers (¥47 to ¥21.90). Contest entry, not an official McDonald's product; China only

Worth knowing

  • Specific numbers (¥47 to ¥21.90). Contest entry, not an official McDonald's product; China only.

Prompt

Cleaned version rewritten from the source — not a direct quote.

I want [a Big Mac meal]. Pull the menu and every coupon I can use at [store], work out every valid combination with code (not mental math), and show me the 3 cheapest options with the total and what's saved. Ask me before placing any order.

Recommended

Try it in Grok Bot

  1. Copy the prompt (button below).
  2. Open Grok Bot chat and paste it. Replace any [bracketed] placeholders.
  3. Connect the listed tools (as needed) as connectors when Grok Bot asks.
  4. If the task repeats, ask: "Make this a daily routine."

Alternatives: the same prompt works in Claude, ChatGPT Agent, OpenClaw.

Set it up

Stack: WorkBuddy agent + McDonald's China MCP

  1. Read the original source for full context.
  2. Connect the tools your agent needs.
  3. Paste the prompt and replace [bracketed] placeholders.
  4. Run once manually and check the output before scheduling it.

Generic suggested steps, not from the source.

Evidence

Specific numbers (¥47 to ¥21.90). Contest entry, not an official McDonald's product; China only

Source: Web · Verified by us: not yet · Report broken or outdated

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