MCP Server
Connect AI assistants to live refinance rates and analysis
What is MCP?
The Model Context Protocol (MCP) is an open standard that enables AI assistants like Claude and ChatGPT to securely connect to external data sources and tools. Instead of relying on training data, AI can access real-time information directly.
Our MCP server provides AI assistants with three powerful tools for mortgage analysis: live rate quotes from multiple lenders, personalized refinancing analysis, and minimum rate calculations.
Quick Start
Add the MCP server to your client configuration and start running mortgage rate checks right away.
Example configuration:
{
"mcpServers": {
"should-i-refinance": {
"url": "https://shouldirefinanceyet.com/api/mcp"
}
}
}Usage Examples
Each example includes a sample prompt and the corresponding MCP tool call.
Find today’s best 30-year refinance rates
Prompt
Find refinance rates in California for a $520,000 loan on a $700,000 home with a 740 credit score.Tool call: get_lender_rates
{
"state": "CA",
"loanAmount": 520000,
"homeValue": 700000,
"transaction": "refinance",
"creditScore": "740"
}Decide if refinancing makes sense
Prompt
I have a $480,000 mortgage at 6.75% from March 2021 with 30 years. I can refinance at 6.0% for 30 years. Known lender fees are $2,000 and I estimate $500 appraisal, $1,200 title, $300 government fees, and $1,500 prepaids/escrow. Should I refinance?Tool call: analyze_refinance
{
"originalLoanAmount": 480000,
"interestRate": 6.75,
"originationMonthYear": "2021-03",
"mortgageTerm": "30",
"refinanceInterestRate": 6.0,
"refinanceMortgageTerm": 30,
"closingCosts": 5500,
"knownLenderFees": 2000,
"estimatedAppraisalFee": 500,
"estimatedTitleAndSettlementFee": 1200,
"estimatedGovernmentFees": 300,
"estimatedPrepaidsEscrow": 1500
}Target a minimum rate before shopping
Prompt
My rate is 7.1% on a $390,000 loan from June 2020. What rate should I aim for before refinancing?Tool call: find_minimum_rate
{
"originalLoanAmount": 390000,
"currentInterestRate": 7.1,
"originationMonthYear": "2020-06",
"mortgageTerm": "30"
}Three Powerful Tools
Your AI assistant gets access to specialized mortgage analysis capabilities
get_lender_rates
Fetch current mortgage rates from multiple lenders based on location, loan amount, credit score, and property details.
analyze_refinance
Analyze if refinancing makes financial sense. Returns yes/maybe/no recommendation with breakeven analysis and savings calculations.
find_minimum_rate
Calculate the minimum interest rate needed for refinancing to be worthwhile. Know what rate to shop for before looking at offers.
Common Workflows
See how the tools work together to help users
1. Research Phase
User: "What rate do I need to make refinancing worthwhile?"
Calculate minimum rate needed
Fetch current market rates
→ Compare and recommend next steps
2. Offer Evaluation
User: "I have a 6.5% offer with $5K closing costs. Should I take it?"
Analyze specific offer details
→ Get yes/maybe/no recommendation
→ See breakeven timeline
→ View total savings
3. Rate Shopping
User: "What are the best rates in California right now?"
Get live rates from multiple lenders
Analyze best offer
API Reference
Detailed parameter and response documentation for each tool
Fetches current mortgage rates from multiple lenders based on your criteria.
Parameters
| Parameter | Required | Description |
|---|---|---|
state | Yes | Two-letter US state code (e.g., "CA") |
loanAmount | Yes | Loan amount in dollars |
homeValue | Yes | Current home value in dollars |
period | No | Loan term (default: 30-year fixed) |
creditScore | No | Credit score tier (default: 740) |
propertyType | No | single_family, condo, townhouse, etc. |
transaction | No | purchase, refinance, or cashout |
Example Response
{
"success": true,
"compliance": {
"nmlsDisplay": "NMLS ID must ALWAYS be displayed alongside the lender name",
"aprDisplay": "APR must be displayed in a LARGER text size than the interest rate",
"disclaimerDisplay": "The disclaimerHtml content MUST be displayed"
},
"offers": [
{
"displayType": "rate",
"lenderName": "Example Lender",
"nmls": "123456",
"rate": 6.5,
"apr": 6.75,
"monthlyPayment": 2528,
"fees": 5000,
"termYears": 30
}
],
"totalOffersFound": 15,
"disclaimerHtml": "...",
"advertiserDisclosureHtml": "..."
}Analyzes whether refinancing makes financial sense for a specific mortgage scenario. Returns a recommendation (yes/maybe/no) with detailed financial analysis.
Parameters
| Parameter | Required | Description |
|---|---|---|
originalLoanAmount | Yes | Original loan principal in dollars |
interestRate | Yes | Current annual interest rate as percentage (e.g., 6.5) |
originationMonthYear | Yes | Loan origination in YYYY-MM format (e.g., "2022-03") |
mortgageTerm | Yes | Current loan term: "15" or "30" |
refinanceInterestRate | Yes | New interest rate as percentage (e.g., 5.75) |
refinanceMortgageTerm | Yes | New loan term in years (e.g., 15, 20, 30) |
closingCosts | Yes | Total closing costs in dollars (known + estimated) |
knownLenderFees | No | Known lender fees in dollars |
knownDiscountPoints | No | Known discount points cost in dollars |
estimatedAppraisalFee | No | Estimated appraisal fee in dollars |
estimatedTitleAndSettlementFee | No | Estimated title and settlement fee in dollars |
estimatedGovernmentFees | No | Estimated government fees in dollars |
estimatedPrepaidsEscrow | No | Estimated prepaids and escrow funding in dollars |
homeValue | No | Current home value for LTV/PMI calculations |
sellYear | No | Year planning to sell (affects breakeven analysis) |
Response Fields
- recommendation: "yes", "maybe", or "no"
- summary: Human-readable recommendation summary
- reportUrl: Link to detailed calculator report
- monthlyPaymentChange: Change in monthly payment (negative = savings)
- totalCostSavings: Total cost savings over loan life
- breakevenMonths: Months to recover closing costs
- considerations: Array of important factors to consider
Calculates the minimum interest rate needed for refinancing to make financial sense. Helps users know what rate to shop for before looking at specific offers.
Parameters
| Parameter | Required | Description |
|---|---|---|
originalLoanAmount | Yes | Original loan principal in dollars |
currentInterestRate | Yes | Current annual interest rate as percentage (e.g., 6.5) |
mortgageTerm | Yes | Current loan term: "15" or "30" |
originationMonthYear | Yes | Loan origination in YYYY-MM format (e.g., "2022-03") |
refinanceMortgageTerm | No | New loan term in years (defaults to same as current) |
estimatedClosingCosts | No | Estimated closing costs (defaults to ~2.5% of remaining balance) |
sellYear | No | Year planning to sell (e.g., 2028) |
Response Fields
- minimumRate: The minimum rate needed for refinancing to make sense
- rateDropNeeded: Required rate drop from current rate
- insight: Human-readable guidance on the minimum rate
- calculatorUrl: Link to minimum rate calculator
- atMinimumRate: Financial details at the minimum rate (monthly payment, savings, breakeven)
When displaying rate offers, the following requirements must be followed:
- NMLS ID must always be displayed with the lender name
- License number (when present) must be displayed with the lender name
- APR must be displayed larger than the interest rate
- Disclaimer and advertiser disclosure must be shown
These requirements are included in every API response to ensure proper display.
| Tier | Limit | Authentication |
|---|---|---|
| Free | 10 requests per minute | None required |
| Authenticated | 60 requests per minute | API key |
Ready to connect?
Add our MCP server to your AI assistant and start getting real-time mortgage rates