All servers · Buy Pro $19 · Source · Claude Desktop bundle (.mcpb)
Loan and lease schedules for an AI assistant. Give it the terms of a credit agreement -- the amount, the nominal annual rate in basis points, how often interest compounds, how often a payment falls due, the term in periods, the method, any arrangement fee and any balloon -- and it works out the payment, the effective annual rate, and the schedule period by period: opening balance, payment, interest, principal, closing balance. It answers what settling early would cost and save, and hands back the double entry for a payment in the same account names the cash book uses. Everything is integer minor units, and every closing balance reaches the balloon, or zero, exactly. Nothing is sent anywhere: the register is a file on your machine.
Claude Desktop -- macOS ~/Library/Application Support/Claude/claude_desktop_config.json, Windows %APPDATA%\Claude\claude_desktop_config.json:
{
"mcpServers": {
"amortization": {
"command": "npx",
"args": ["-y", "@theluckystrike/mcp-amortization"]
}
}
}
Claude Code
claude mcp add amortization -- npx -y @theluckystrike/mcp-amortization
Cursor -- ~/.cursor/mcp.json (global) or .cursor/mcp.json (project). Same entry as Claude Desktop.
| Tool | What it does |
|---|---|
loan_create |
Record a loan or lease from its terms. Returns LOAN-YYYY-NNNN, the level payment, the effective annual rate and the total interest |
loan_schedule |
The schedule: opening, payment, interest, principal, closing for every period, and the total interest |
loan_repay_early |
What settling or overpaying at a period costs: the outstanding balance, the penalty, the recalculated remaining schedule and the interest saved, gross and net of the penalty |
loan_journal |
The double entry for a period or a month: debit interest expense and loan liability, credit cash, plus an expense_add-ready payload |
loan_list |
The register, with the balance outstanding and the next payment date at any date |
loans_report |
What is owed per currency, when each next payment falls due, and the interest charged in a calendar year |
license_status, license_activate |
Your tier, and activating a Pro key |
| Free | Pro | |
|---|---|---|
| Loans in the register | 3 | Unlimited |
| Schedules | Unlimited | Unlimited |
Early repayment (loan_repay_early) |
- | Yes |
Journals (loan_journal) |
- | Yes |
Report (loans_report) |
- | Yes |
The schedule is never metered. The payment and the interest are the question this server exists to answer, and a free tier that hides the answer is a demo. The meter is on the number of agreements held, which is the unit of work.
Get Pro: https://mcp.zovo.one/buy/amortization -- $19 one-time for this server, or $39 for the bundle.
Quoting a rate per quarter as the nominal rate over four is worth 1.0 percent of the interest, in the lender's favour. Take EUR 10,000 at a nominal 12 percent compounded MONTHLY, repaid in four quarterly instalments. The rate for one quarter is the equivalent rate, (1 + 0.12/12)^3 - 1 = 3.0301 percent, not 0.12/4 = 3.0000 percent. That 3-basis-point difference sets the payment at EUR 2,692.21 instead of EUR 2,690.27 and the total interest at EUR 768.84 instead of EUR 761.08: EUR 7.76 more, 1.0 percent of the whole interest bill, on a one-year loan of ten thousand. The two rates look identical in a quote and diverge in the schedule, which is why this server takes every equivalent rate through the compounding clock and prints the periodic rate it used to six decimal places.
The same arithmetic is why the effective annual rate is reported beside the nominal one on every loan: a nominal 12 percent compounded monthly is an effective 12.68 percent, and 0.68 of a percent is the part of the price the headline rate does not carry.
All data stays local, in ${XDG_DATA_HOME:-~/.local/share}/mcp-servers/amortization/. Two files: loans.json and counter.json. No network call is made by this server at all, for any tool. No schedule is stored: every row is derived from the terms on the call, because a stored schedule is a second copy of a figure the rate and the term already decide, and the copy is the one that gets believed after somebody edits the rate.
Built by theluckystrike. https://github.com/theluckystrike
Three prompts that scored 3 of 3, measured in round 31, 2026-09-06. Paste one in as it is written.
I am about to sign for a van on finance: 10,000 EUR, they quote 12 percent a year, interest compounds monthly, twelve monthly payments, drawdown 15 January 2026. Record it as "Van finance" and tell me plainly what it costs me.
Paste this into Claude with the server connected.
What it did, measured in round 31, 2026-09-06: It volunteered the nominal-versus-effective distinction unprompted and in the user's own words, and it flagged the two terms the user had not mentioned rather than assuming them silently.
Show me the whole schedule. I want to see where the interest goes.
Paste this into Claude with the server connected.
What it did, measured in round 31, 2026-09-06: loan_schedule is free and unlimited by design and carried no checkout link, which is what the free tier is for.
The last row looks off to me. Every other period the interest is just the balance times one percent, but period 12 charges more than that on a balance of 879.67. Is that a bug?
Paste this into Claude with the server connected.
What it did, measured in round 31, 2026-09-06: Challenged directly on a figure that looks wrong, it neither backed down nor bluffed: it reproduced the design decision from the server's own words, named the number the other convention would produce, and told the user what to compare against the paperwork.
On the free tier for this path: loan_schedule is free and unlimited on every tier: the payment and the interest are the question this server exists to answer, and a free tier that hides the answer is a demo. The meter is on the number of agreements held, three loans in the register, which is the unit of work.
Or the nineteen-server bundle for $39.
Exact config path, entry and caveats: Claude Desktop · Claude Code · Cursor · VS Code · Windsurf · Cline · Claude.ai and Claude Desktop connectors · all clients
How to track billable hours inside Claude Code and Cursor · Create an invoice PDF from a chat message with an MCP server · Ask questions about an Excel or CSV file from Cursor or Claude · Watch a product price with Claude and get told when it drops · What the free tier includes and what Pro adds · Log expenses and mileage in Claude, split VAT, rebill to an invoice · Convert currencies in Claude with real ECB rates, no API key · Generate Word proposals and contracts from a chat message · Find a meeting time across time zones without doing the arithmetic · Write a resume and a cover letter from chat, without inventing anything · Bill a retainer on a schedule without a billing SaaS · Assemble a contract from your own clause library, in chat · Connect MCP servers to Claude.ai, Claude Desktop, Cursor and VS Code without installing anything · Merge, split and stamp PDFs from chat, and why some come back as glyph numbers · Read a .ics calendar in Claude: free and busy, conflicts, and billable meetings · Run a kanban board in Claude, with time tracking on the same task · Resize, compress and watermark images from a chat message · Categorize and reconcile a bank CSV export from chat · Send a quote from chat, then turn the yes into an invoice · Put a SEPA payment QR code on an invoice from chat · Zip and unzip archives safely from Claude or Cursor · Client deposits and retainers from chat, applied to your real invoices · Fixed assets and depreciation from chat, on the rates the tax authorities publish · Per diem and travel allowances from chat, on the rate tables the tax authorities publish · One double-entry ledger out of every server you already run · Loan and lease schedules from chat, closing exactly on zero · Client statements and payment chasers from chat, aged as at any date you name · Credit notes and purchase orders from chat, against your real invoices · One install, every server: the office-suite bundle · Close a month in chat: invoice, credit note, retainer, bank reconciliation, statement · All guides