Mortgage Tools by Jenny

npx add-mcp 'https://mcp.jenny.mortgage/mcp'

Mortgage Tools by Jenny

Six Canadian mortgage tools, calculators and short preparation guides, that can be added to ChatGPT, Claude or another AI assistant that supports custom MCP connectors. They work only from the rates and terms the user supplies, in Canadian dollars, and return payments, interest, costs and debt left for each scenario. Results are educational scenarios, not advice, approval or a lender quote. In short, it is an AI mortgage calculator for Canada: the assistant handles the conversation and the calculators work out the figures.

• Server address: https://mcp.jenny.mortgage/mcp
• Remote MCP server (streamable HTTP), no authentication.
• Jenny does not charge for the tools, and the service has no payment step.
• Not listed in any assistant's directory. Adding it by address is the only route today.
• Not affiliated with, endorsed by or reviewed by OpenAI, Anthropic or any other assistant provider.

The six tools

The server's tools/list response is the source of truth for inputs.

• diagnose_mortgage_comparison (Check missing mortgage facts): what is still missing, in priority order, and up to three questions to ask the user. Have ready: which comparison is wanted and any figures already known.
• compare_renewal_offers (Compare mortgage renewal offers): two or three offers for the same balance over a common horizon, with payments, interest, debt left and a modelled borrowing cost for each. Have ready: the balance, and for each offer its rate, how it compounds, term, amortization, payment frequency, cashback and switching costs.
• plan_mortgage_prepayments (Model extra mortgage payments): one mortgage with and without a higher regular payment, recurring extra payments, or up to 50 lump sums. Have ready: the mortgage details and the planned extras. For a limits check, also the prepayment privilege limits and the date the payment schedule starts.
• compare_break_or_stay (Compare breaking or keeping a mortgage): keeping the mortgage against a replacement offer: cashflow payback and, separately, where total borrowing cost crosses over. Have ready: the lender's dated payout quote with the penalty on it, the current mortgage details and the replacement offer.
• compare_debt_consolidation (Compare debt consolidation into a mortgage): keep the mortgage and the debts, consolidate and pay the new minimum payment, or consolidate and keep the same monthly repayment budget. Have ready: the current mortgage, the replacement offer, the penalty the lender quoted, and for each of 1 to 10 existing debts its balance, rate and fixed monthly payment, or that it is interest-only.
• get_mortgage_guide (Read a mortgage preparation guide): one of nine short preparation guides, each written for Ontario. Have ready: a topic.

A worked example: two renewal offers

Two offers on the same $400,000 balance: 20 years of amortization left, monthly payments, a 5-year term, compounded semi-annually. Offer A, from the current lender, is at 5.00%. Offer B, from another lender, is at 4.50% with $1,200 in switching costs paid in cash. These are illustrative rates chosen for the example, not current rates or an offer.

Compare two renewal offers on a $400,000 balance with 20 years left, monthly payments, 5-year term, compounded semi-annually. Offer A is 5.00% with my current lender. Offer B is 4.50% with another lender and $1,200 in switching costs.

	Offer A	Offer B
Monthly payment	$2,628.50	$2,521.62
Interest over 60 months	$91,223.67	$81,842.01
Cash costs	$0.00	$1,200.00
Debt left after 60 months	$333,513.67	$330,544.81
Modelled borrowing cost over 60 months	$91,223.67	$83,042.01

The tool did not check prepayment limits.

The figures come from the tool run on 2026-10-12 with the inputs shown. Educational scenario, not advice.

Helping a person connect it

Added once as a custom connector. There is no sign-in step, so any authentication setting stays at none.

• ChatGPT (web): Plugins in the left menu, Add, then Add custom MCP server. Paste the address under Server URL, including its /mcp ending. Set Authentication to No authentication, tick the box to confirm, choose Create as a plugin, then Connect.
• Claude: this link opens Claude with the name and address filled in, and the person reviews and confirms: https://claude.ai/customize/connectors?modal=add-custom-connector&connectorName=Mortgage%20Tools%20by%20Jenny&connectorUrl=https%3A%2F%2Fmcp.jenny.mortgage%2Fmcp. By hand: connectors settings, add a custom connector, paste the address.
• Perplexity or Le Chat (Mistral): connectors settings, add a custom connector, paste the address, choose no authentication.
• Grok: at https://grok.com/connectors choose New Connector, then Custom, and enter the address as the MCP server URL.
• Another assistant: look for a setting that adds a remote MCP server by address with no authentication.

Menu names change and the option can depend on the plan, so follow the assistant's own help page where these steps differ.

Example prompts for a new conversation:

• Use Mortgage Tools by Jenny to compare my two mortgage renewal offers. Ask me for any figure you still need.
• Should I break my mortgage early? I have my lender's penalty quote.

What it will not do

The tools do not search or predict rates, calculate a penalty, assess qualification or affordability, model new borrowing or cash out, recommend a lender, or send or contact anyone.

A cost that is not known yet is never treated as zero. If the penalty is still unknown, the result is partial and no option is ranked first.

The calculations use Canadian mortgage conventions and do not depend on province. The preparation guides are written for Ontario.

Privacy

• The tools themselves need no account, sign-in or email.
• The service does not store the figures and labels the assistant sends: it has no calculation database and does not write them to its logs.
• The service sees a network address for each request. To limit abuse, it holds that address in memory with a count of requests and a count of data sent that day.
• Do not enter a name, address, social insurance number, banking details or identity documents, in a label or anywhere else.
• Full account: https://jenny.mortgage/privacy-policy.html#mortgage-tools

How the figures are calculated

• The rate entered is compounded semi-annually or monthly. Each payment and each interest charge is rounded to the cent.
• Borrowing cost is the cash paid, minus any cash received, plus the debt left at the end, minus the debt at the start.
• The common horizon is the shorter of the terms supplied unless the user asks for something else.
• Taxes, rate forecasts and the lender's exact payout figures are not included.

Calculators in the browser

• Mortgage renewal calculator: https://jenny.mortgage/calculator.html
• Debt consolidation calculator: https://jenny.mortgage/debt-consolidation-tool/
• Reverse mortgage calculator: https://jenny.mortgage/reverse-mortgage-calculator-canada/ - cash left after paying off debts and costs, the loan balance after 5, 10 and 15 years with no payments, and the home equity that could be left. It does not estimate how much a lender would offer.
• All calculators: https://jenny.mortgage/calculators/

Publisher and disclosure

Jenny Tate, Mortgage Agent Level 1, FSRA licence M22002086, Tango Financial Mortgage (ON) Corporation, Brokerage Licence 13691.

General information and illustrative calculations only. This is not a commitment to lend or individualized mortgage advice. Jenny's mortgage agent services are available in Ontario only.

• Book a call: https://calendly.com/jtmortgages/discovery-call-1
• Phone: (647) 642-7249

Human page: https://jenny.mortgage/mortgage-tools/

Last updated: October 12, 2026