If the Card Fits
Find the best credit cards for your household spending and see what they're worth over 5 years.
Simulates credit card rewards and fees against your spending by category. Recommends the best single cards and two-card combinations, accounts for memberships and travel frequency, and tells you whether cards you already carry still pay for themselves.
Try asking Muse: "Which two credit cards should I carry to maximize rewards on my groceries, dining, and travel spending?"
See the most upvoted connectors
Source: Found in the official MCP Registry (io.github.sjgiewont/if-the-card-fits) · First listed October 30, 2026
Last 24 hours
Each bar is one check, every 15 minutes. Green means it answered. Last checked 2 h ago.
Is it safe to connect?
What Muse can see: It does not ask you to sign in, so it cannot see your accounts. It only sees what Muse sends it from your request.
Before it acts: Read what Muse plans to do before you approve it, and remove the app from Muse when you stop using it.
musedirectory.ai is not part of Meta. More about how Muse handles your information
How to add it to Muse
Not in Muse's Connectors list yet, but Muse can still use it. Copy the request below and paste it into Muse. Muse asks before it shares anything with the app's site. Meta does not review apps used this way, so only use ones you trust. We tested this in the Muse app on September 24, 2026: Muse used an app's link directly this way and returned a live answer.
https://ifthecardfits.com/mcpNot in Muse's Connectors list yet. Muse can still use it: its page gives you a request to paste into Muse.
Also use it in ChatGPT or Claude
If the Card Fits is a remote MCP server, so any assistant that can add a custom connector by link can use it. Same link, same tools.
Add it to ChatGPT
- 1
Open ChatGPT settings
In ChatGPT, open Settings, then Connectors (called Apps & Connectors on some accounts).
- 2
Turn on developer mode
Under Advanced settings, switch on Developer mode. That is what lets you add a connector by link.
- 3
Create the connector
Choose Create, give it a name, paste the link as the MCP server URL, and save. If it needs a sign-in, ChatGPT asks for it here.
- 4
Use it in a chat
Start a chat, open the tools menu, pick the connector, and ask. ChatGPT asks before it runs a tool the first time.
Custom connectors need a paid ChatGPT plan, and on Team, Enterprise and Edu accounts only an admin can add them. Our "Working" label means the server answered us; it cannot tell whether your plan lets you add it. All connectors that work in ChatGPT
Add it to Claude
- 1
Open Claude settings
In Claude, open Settings, then Connectors.
- 2
Add a custom connector
Choose Add custom connector, give it a name, and paste the link.
- 3
Connect and use it
If it needs a sign-in, Claude sends you to it. Then turn the connector on in a chat from the tools menu and ask.
Custom connectors are available on paid Claude plans; on Team and Enterprise accounts an admin may need to add them. Our "Working" label means the server answered us; it cannot tell whether your plan lets you add it. All connectors that work in Claude
https://ifthecardfits.com/mcpWhat people ask Muse to do
Technical details: safety screening, tools, response time and recent checks
Response time at the last check: 1082ms. Worked in n/a of checks over 30 days.
Screening · October 30, 2026
Screened, no issues found
Screening looks for known threats and hidden instructions at the time of the check, and runs again weekly and whenever the tool list changes. It cannot see the server's code, so only connect what you need and review what Muse asks to do. How screening works.
Tools · 4
spending_categoriesThe 19 categories this API scores spending against. Call this first and map the person's statement onto these ids before calling simulate_cards.simulate_cardsGiven a year of spending by category, returns the three best credit cards and the best two-card combination, with what each is worth after its annual fee over the chosen horizon. Figures come from a model checked to the cent against an independent reference calculator, against cakeep_or_cancelFor cards the person already carries, says whether each one still earns its annual fee back on their spending, and what to move to if not. Pass the cards as `held`. Returns a verdict and a rounded yearly margin.compare_twoTwo named cards head to head on the person's own spending: which one pays more, and by how much a year. Use this when they are choosing between two specific cards. For 'what should I get', use simulate_cards instead.Link
https://ifthecardfits.com/mcpQuestions about If the Card Fits in Muse
How do I connect If the Card Fits to Muse?
Not in Muse's Connectors list yet, but Muse can still use it. Paste this into Muse: "Use If the Card Fits to help me. It is a free service with an MCP server at https://ifthecardfits.com/mcp. It does not need an API key. Ask me before you share anything with it." Muse asks before it shares anything with the app's site. Meta does not review apps used this way, so only use ones you trust. We tested this in the Muse app on September 24, 2026: Muse used an app's link directly this way and returned a live answer.
Is If the Card Fits working right now?
At the last check (October 30, 2026, 02:16 UTC) the endpoint was working, answering in 1082ms. It is checked every 15 minutes.
Is If the Card Fits safe to connect to Muse?
It was screened on October 30, 2026 with the result "screened, no issues found". Screening checks the domain against threat feeds and reads the tools for hidden instructions and requests for passwords or card numbers. It cannot see the server's code, so grant only the access you need.
What can If the Card Fits do in Muse?
It exposes 4 tools, including spending_categories, simulate_cards, keep_or_cancel, compare_two. For example, you could ask Muse: "Which two credit cards should I carry to maximize rewards on my groceries, dining, and travel spending?"
Follow If the Card Fits
Made this app? Claim it or get a status badge
Is this yours?
This listing was added from public sources (Found in the official MCP Registry (io.github.sjgiewont/if-the-card-fits)). If you build If the Card Fits, claim it to correct the details and get your badge.
Paste this on your site or README. It always shows the latest check.
<a href="https://musedirectory.ai/connector/if-the-card-fits"><img src="https://musedirectory.ai/badge/if-the-card-fits.svg" alt="If the Card Fits on musedirectory.ai" width="236" height="40"></a>