Mortgage Rates Today MCP

mortgage-rates-today-mcp

Mortgage rates today for AI assistants. Ask for this week's average 30-year or 15-year fixed rate and get the Freddie Mac number, the change from last week and a year ago, and what it means for a monthly payment.

This is a Model Context Protocol (MCP) server. It reads the Freddie Mac Primary Mortgage Market Survey (PMMS) at call time. It needs no API key.

Tools

Tool	What it returns
get_mortgage_rates_today	This week's Freddie Mac average 30-year and 15-year fixed rates, the change from last week and a year ago, the 52-week high, low and average, the week date and the next release date.
get_mortgage_rate_on_date	The weekly average in force on any date since April 1971, with the 5/1 ARM and points where Freddie Mac published them.
get_mortgage_rate_history	Weekly rows or monthly or annual averages for a date range, with the high, low and change.
calculate_mortgage_payment	Monthly principal and interest at today's average (or any rate), compared with the average a year earlier.

Every result has structured JSON, a one-paragraph summary, as_of, source (freddiemac.com/pmms), the data file URL and more (a page on mcpstamp.com). Results carry the Freddie Mac attribution.

What it knows that your model does not

• This week's rate. Freddie Mac publishes a new national average every Thursday at noon Eastern, so any number in a model's training data is out of date.
• The exact weekly history since 1971, for questions like "what was the rate when I bought in March 2021".
• Payment math tied to the current average, so the comparison with a year ago uses real numbers.

Install

Hosted (Claude.ai custom connector, ChatGPT developer mode)

Paste this URL. No token, no sign-up. It works now.

https://mortgage-rates-today-mcp.lipmichal.workers.dev/mcp

Claude Code

claude mcp add --transport http mortgage-rates https://mortgage-rates-today-mcp.lipmichal.workers.dev/mcp

Claude Desktop

Claude Desktop adds remote servers under Settings, Connectors, Add custom connector. Paste the URL above.

Cursor

Add to ~/.cursor/mcp.json:

{
  "mcpServers": {
    "mortgage-rates": { "url": "https://mortgage-rates-today-mcp.lipmichal.workers.dev/mcp" }
  }
}

VS Code

Add to .vscode/mcp.json:

{
  "servers": {
    "mortgage-rates": { "type": "http", "url": "https://mortgage-rates-today-mcp.lipmichal.workers.dev/mcp" }
  }
}

Local stdio (after npm release)

The npm package is not published yet. After it is, run it locally with Node 20 or newer:

claude mcp add mortgage-rates -- npx -y mortgage-rates-today-mcp

Example prompts

• "What are mortgage rates today?"
• "What is the average 30-year fixed mortgage rate this week, and is it up or down?"
• "What was the 30-year mortgage rate in January 2021?"
• "Show me the monthly average 15-year rate since 2024."
• "What is the monthly payment on a $400,000 loan at today's rate, compared with a year ago?"

Data sources

Full list with fetch dates in DATA_SOURCES.md.

• Freddie Mac Primary Mortgage Market Survey, history file PMMS_history.csv. Source: Freddie Mac.

Limitations

• PMMS is a national weekly average for well-qualified conventional purchase borrowers with 20 percent down. It is not a quote. Your rate depends on credit, down payment, points, loan type, state and lender.
• No daily rates, no FHA, VA or jumbo series, and no ARM data after November 2022.
• The hosted server caches the file for up to an hour, so a new Thursday release can take up to an hour to appear.
• Payments exclude taxes, insurance, PMI and HOA dues.

More

More MCP servers that answer questions your assistant cannot answer alone are on mcpstamp.com.

Part of the Zovo MCP collection: https://mcp.zovo.one

Built by theluckystrike.

Development

npm install
npm test                              # builds, then runs the fixture tests and an offline stdio test
node scripts/stdio-transcript.mjs     # live stdio round trip, writes .live/stdio-transcript.jsonl

License

MIT