RightCard MCP: which card should your agent pay with?

Free · open source · no bank login · nothing stored

AI assistants are starting to shop and book for people. At some point every one of them has to pick a card, and today it picks "the one on file." That is the wrong-card problem, moved into software. RightCard already answers "which card, here, today" from verified bank data. This server lets any agent ask.

What it looks like

You: I have the Amex Gold, Freedom Flex and Citi Double Cash. Which one at Costco?

Use the Citi Double Cash, 2%. Costco codes as a warehouse club, so category bonuses usually don't post there; the flat card is your best guaranteed earn.

You: Same cards, Whole Foods, I redeem for travel.

Amex Gold. 4x Membership Rewards at 2.0¢ each is about 8% per dollar. Whole Foods is a supermarket code, so the grocery rate applies.

You: Gas this quarter?

Freedom Flex, 5% through September 30. Activation required in the Chase app.

Add it to your assistant

Hosted endpoint (stateless, nothing stored):

https://mcp.rightcard.ai/mcp

Claude Desktop, Claude Code, Cursor and most MCP clients take a remote server by URL. In Claude Code:

claude mcp add --transport http rightcard https://mcp.rightcard.ai/mcp

Or run it on your own machine (the only network call is a read of the public card catalog):

npx -y rightcard-mcp

Claude Desktop, Cursor and most MCP clients take this config for the local server:

{ "mcpServers": { "rightcard": { "command": "npx", "args": ["-y", "rightcard-mcp"] } } }

Then tell it which cards you hold, in plain words. It will look up the ids itself.

Where to find it: npm (rightcard-mcp) · the official MCP Registry (ai.rightcard/mcp, domain-verified) · Smithery · source on GitHub.

The tools

Tool	What it answers
`best_card`	Which of the given cards earns most at a store or category, today, with the honest caveats: merchant-code traps, activation, ties.
`lookup_merchant`	How a store is coded. "Does Walmart count as grocery?" as an API.
`search_cards`	Card ids by name or issuer. Verified cards first; unverified cards flagged, never hidden.
`card`	One card's verified rates, live rotating windows, and choose-your-category rules.
`rotating_calendar`	Live and upcoming 5% windows, from the same data as the calendar pages.

The rules it follows

Verified only. Rates come from RightCard's pipeline, published only after two independent sources agree. A card that hasn't cleared that bar is named as unverified, not ranked as fact.
Honest value. Cash by default. Ask for points valuation and it uses conservative per-program travel values and shows the math, so a hotel 5x never reads like 5% cash.
The trap is part of the answer. Superstores and warehouse clubs get the caveat every time.
Same answers as the app. The server is a port of the iOS engine, checked against 3,000+ answers produced by the app's own code before every release.

Privacy, plainly: the server receives a list of card ids and a store name per request and returns an answer. No account, no login, no cookies, no storage. Your personal bank offers stay on your phone; the MCP never sees them. Source: github.com/rightcard/rightcard-mcp; full policy at rightcard.ai/privacy.

Get RightCard on the App Store

FAQ

What is the RightCard MCP?

A free MCP (Model Context Protocol) server that lets an AI assistant or agent ask RightCard which of a person's credit cards to use at a store or for a category. It runs on RightCard's verified, bank-published reward data.

Does it need my bank login?

No. It takes a list of card ids and a store name. It never sees bank credentials, balances, or transactions, and it stores nothing.

Which AI assistants can use it?

Anything that speaks MCP: Claude Desktop, Claude Code, Cursor, ChatGPT connectors, and custom agents. It runs hosted over HTTP or locally over stdio with npx.

Does it know about my bank offers?

No. Personal bank offers synced by the RightCard app stay on your phone by design. The MCP answers from base rates, rotating quarters, and built-in card benefits.

More: All guides · Privacy label comparison · Why didn't my grocery bonus post?