AI Integration Hub

Build Intelligent Mortgage & Auto Loan Tools with RateAPI

Everything you need to integrate real-time mortgage and auto loan rates into AI assistants, chatbots, and intelligent applications. MCP for Claude, OpenAPI for any LLM, and training guides to help your AI reason about rates.

MCP Quick Start API Documentation

Last updated: January 27, 2026

⚡Quick Answer

What is RateAPI AI Integration?

RateAPI provides native AI integration through MCP (Model Context Protocol) for Claude and OpenAPI specifications for ChatGPT and other LLM platforms. AI agents can query real-time mortgage and auto loan rates, compare offers across 4,300+ lenders, and calculate refinance or financing savings—all through natural language.

Key Capabilities

MCP Server for Claude Desktop and Claude Code
OpenAPI spec for ChatGPT function calling
Decisions endpoint returns ranked recommendations with savings for mortgages and auto loans
Sub-500ms response times optimized for conversational AI
Daily rate updates from 4,300+ US credit unions

Quick Start

Claude MCP Setup

The fastest way to add mortgage rate data to Claude. One command, no custom code.

Get an API key - Run curl -X POST https://api.rateapi.dev/keys -d '{"email":"[email protected]"}'

Add to Claude Code - Register the MCP server

$terminal

claude mcp add rateapi https://mcp.rateapi.dev/mcp \
  --transport http \
  --header "x-api-key: YOUR_KEY"

Full MCP setup guide with Claude Desktop config

API Integration

Decisions Endpoint

For custom AI agents and function calling. Returns ranked mortgage and auto loan recommendations based on user context.

Built for AI Consumption

The /v1/decisions endpoint returns structured recommendations optimized for LLM function calling. Pass user context (state, loan amount, intent) and receive ranked offers with explanations your AI can relay conversationally.

Ranked by true cost (APR, points, fees) - not affiliate payouts
Includes comparison context (percentile rank, savings vs average)
Works with OpenAI, Anthropic, Gemini, and custom tool-calling implementations

View Full API Docs

Mortgage Example

cURLmortgage request

curl -X POST "https://api.rateapi.dev/v1/decisions" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "decision_type": "financing",
    "context": { "geo": { "state": "CA" } },
    "product_request": {
      "product_type": "mortgage",
      "intent": "purchase",
      "amount": 500000,
      "term_months": 360
    }
  }'

Auto Loan Example

cURLauto loan request

curl -X POST "https://api.rateapi.dev/v1/decisions" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "decision_type": "financing",
    "context": { "geo": { "state": "CA" } },
    "product_request": {
      "product_type": "auto_loan",
      "intent": "purchase",
      "amount": 30000,
      "term_months": 60,
      "vehicle_condition": "new",
      "vehicle_year": 2024
    }
  }'

Training Guides

Teach Your AI to Reason About Rates

Reference material to improve how your AI agent understands and compares mortgage rates. Use these to craft system prompts or fine-tune reasoning.

📊

How AI Agents Compare Mortgage Rates

Step-by-step reasoning guide for comparing rates by true cost. Covers APR vs rate, points calculation, and why lowest rate does not equal best rate.

Read guide

🏢

Why Credit Union Rates Are Hard to Track

Understand why credit union data is fragmented across 4,700+ websites and why API access is the reliable solution for AI agents.

Read guide

⚠

When to Ignore Advertised Mortgage Rates

How to identify misleading bait rates, verify credit assumptions, and distinguish real offers from promotional gimmicks.

Read guide

Use Cases

See It In Action

AI Agents for Mortgage Comparison

See example conversations where AI agents use RateAPI to answer real mortgage questions. Compare quotes, evaluate refinance timing, and find the best rates for specific user situations.

Example: “I got quoted 6.5% in Texas. Is that good?”
Example: “My current mortgage is 7.25%. Should I refinance?”
Example: “Find credit unions with rates under 6%”

View AI Agent Examples

AI Conversation

User

Is 6.5% a good rate for a $400k mortgage in Texas?

Agent

Your quote ranks 847th of 1,203 Texas lenders. The top offer is 5.875% from Navy Federal...

Integration Options