# RateAPI - Complete LLM Context

> The rate API built for AI agents. Real-time rates for mortgages, auto loans, HELOCs, personal loans, and credit cards from 4,300+ US credit unions.

This document provides comprehensive context about RateAPI for large language models. It includes full documentation of our API, data methodology, credit union coverage, and integration options.

---

## Table of Contents

1. [Overview](#overview)
2. [Quick Facts](#quick-facts)
3. [API Documentation](#api-documentation)
4. [MCP Integration](#mcp-integration)
5. [Discord Bot](#discord-bot)
6. [Data Methodology](#data-methodology)
7. [Credit Union Coverage](#credit-union-coverage)
8. [Widget Integration](#widget-integration)
9. [FAQ](#faq)
10. [Use Cases](#use-cases)
11. [AI Integration Hub](#ai-integration-hub)
12. [AI Training Guides](#ai-training-guides)
13. [Contact & Resources](#contact--resources)

---

## Overview

RateAPI provides programmatic access to mortgage rates from credit unions across the United States. We aggregate, normalize, and verify rate data from 4,300+ credit unions, making it available through a clean REST API and Model Context Protocol (MCP) server.

### What We Provide

- **Real-time mortgage rate data** from credit unions nationwide
- **Sub-500ms response times** via global CDN
- **Daily automated updates** with verified data freshness
- **Both REST API and MCP** integration options
- **Transparent methodology** with no pay-to-rank

### Key Differentiators

- **Built for AI Agents**: Native MCP support for Claude, function calling for ChatGPT
- **Neutral Data**: No affiliate relationships, no lead selling, rates sorted by APR
- **Full Transparency**: Source URLs, timestamps, and methodology documentation
- **Developer-Friendly**: No signup required for API key, free tier available

---

## Quick Facts

| Attribute | Value |
|-----------|-------|
| Coverage | 4,300+ credit unions tracked |
| Products | Mortgages, Auto Loans, HELOCs, Personal Loans, Credit Cards |
| Mortgage Types | 30-year fixed, 15-year fixed, ARM mortgages |
| Auto Loan Types | New vehicle, used vehicle, refinance (36-84 month terms) |
| HELOC | Variable rate (margin over prime), intro rates, draw periods |
| Personal Loans | Secured and unsecured, debt consolidation |
| Credit Cards | Purchase APR, balance transfer, rewards |
| Update Frequency | Daily automated scraping |
| Response Time | <500ms via global CDN |
| Free Tier | 20 requests per 30 days (50 with email) |
| Paid Plans | Starter ($9/mo), Pro ($49/mo), Enterprise (custom) |
| Geographic Coverage | All 50 US states |

---

## API Documentation

### Base URL

```
https://api.rateapi.dev
```

### Authentication

API requests require an API key passed via the `X-API-Key` header or `Authorization: Bearer` header.

```bash
# Create a free API key (no signup required)
# Basic: 20 requests/month
curl -X POST https://api.rateapi.dev/keys

# With email: 50 requests/month (2.5x bonus)
curl -X POST https://api.rateapi.dev/keys \
  -H "Content-Type: application/json" \
  -d '{"email": "you@example.com"}'
```

Response:
```json
{
  "id": "a1b2c3d4e5f6",
  "key": "rk_live_abc123...",
  "message": "Store this key securely - it cannot be retrieved again",
  "tier": { "name": "Free", "limit": 50, "windowDays": 30 },
  "emailRegistered": true
}
```

### Rate Limits by Tier

| Tier | Name | Limit | Price |
|------|------|-------|-------|
| 1 | Free | 20/month | $0 |
| 2 | Starter | 1,000/month | $9/mo |
| 3 | Pro | 10,000/month | $49/mo |
| 4 | Enterprise | Unlimited | Custom |

### Endpoints

#### POST /v1/decisions - Get Personalized Recommendations

The primary endpoint for getting mortgage recommendations. Submit borrower context and receive ranked actions with explanations.

**Request Body:**

| Field | Type | Required | Description |
|-------|------|----------|-------------|
| `decision_type` | string | Yes | Must be `"financing"` |
| `context.geo.state` | string | Yes | 2-letter US state code |
| `product_request.product_type` | string | Yes | `"mortgage"` |
| `product_request.amount` | number | Yes | Loan amount in dollars |
| `product_request.term_months` | number | Yes | Loan term (360 for 30-year, 180 for 15-year) |
| `current_offer` | object | No | Compare against user's existing offer |
| `preferences` | object | No | Filtering preferences (no_points, max_providers, etc.) |

**Example Request:**
```bash
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",
      "amount": 500000,
      "term_months": 360
    }
  }'
```

**Example Response:**
```json
{
  "request_id": "dec_abc123",
  "decision_type": "financing",
  "as_of": "2026-01-23T06:00:00Z",
  "summary": {
    "recommended_action": "shop_providers",
    "confidence": 0.85,
    "estimated_savings": { "monthly": 131, "total": 47200 }
  },
  "actions": [{
    "type": "shop_providers",
    "priority": 1,
    "score": 0.85,
    "why": ["Found 15 credit unions with competitive rates in California"],
    "tradeoffs": ["Requires credit union membership"],
    "expected_outcome": {
      "rate_range": { "min": 6.125, "max": 6.875 },
      "monthly_payment": 2450
    },
    "offers": [{
      "rank": 1,
      "credit_union_name": "Navy Federal Credit Union",
      "apr": 6.284,
      "rate": 6.125,
      "points": 0,
      "monthly_payment": 2450,
      "estimated_monthly_savings": 131
    }]
  }],
  "disclosures": ["Rates subject to change", "Credit union membership required"]
}
```

#### GET /meta - Dataset Metadata

Returns metadata about the dataset including available filters and ranges.

**Example Response:**
```json
{
  "generatedAt": "2026-01-23T06:00:00Z",
  "count": 1500,
  "productTypes": ["15-year-fixed", "30-year-fixed", "5/1 ARM", "7/1 ARM"],
  "institutions": ["Navy Federal Credit Union", "Pentagon Federal Credit Union", ...],
  "ranges": {
    "rate": { "min": 5.125, "max": 8.750 },
    "apr": { "min": 5.247, "max": 8.892 },
    "points": { "min": 0.0, "max": 3.0 }
  }
}
```

#### GET /credit-unions - List Credit Unions by State

Returns all credit unions grouped by US state with rate availability info.

**Example Response:**
```json
{
  "generatedAt": "2026-01-23T06:00:00Z",
  "totalStates": 50,
  "totalCreditUnions": 4000,
  "states": [
    {
      "code": "ca",
      "name": "California",
      "count": 120,
      "verifiedLast7Days": 115,
      "creditUnions": [
        {
          "id": "navy-federal",
          "name": "Navy Federal Credit Union",
          "slug": "navy-federal-credit-union",
          "city": "Vienna",
          "url": "https://www.navyfederal.org/rates",
          "hasRates": true,
          "productCount": 3,
          "lastVerified": "2026-01-23T10:00:00Z"
        }
      ]
    }
  ]
}
```

#### GET /credit-unions/{state}/{slug} - Credit Union Profile

Returns detailed info and all mortgage rates for a specific credit union.

**Path Parameters:**
- `state` - 2-letter US state code (e.g., `va`, `ca`)
- `slug` - URL-friendly credit union name (e.g., `navy-federal-credit-union`)

**Example Response:**
```json
{
  "id": "navy-federal",
  "name": "Navy Federal Credit Union",
  "slug": "navy-federal-credit-union",
  "state": "VA",
  "stateName": "Virginia",
  "city": "Vienna",
  "url": "https://www.navyfederal.org/rates",
  "lastVerified": "2026-01-23T10:00:00Z",
  "rates": [
    {
      "productType": "30-year-fixed",
      "productName": "30 Year Fixed Rate Mortgage",
      "rate": 6.25,
      "apr": 6.375,
      "points": 0,
      "lastUpdated": "2026-01-23T10:00:00Z"
    }
  ]
}
```

### Response Headers

| Header | Description |
|--------|-------------|
| `X-RateLimit-Limit` | Maximum requests allowed per 30-day window |
| `X-RateLimit-Remaining` | Requests remaining in current window |
| `X-RateLimit-Reset` | ISO 8601 timestamp when limit resets |
| `X-Cache` | Cache status: `HIT` or `MISS` |
| `X-Cache-Version` | Current cache version identifier |

### Error Responses

```json
{
  "error": "Rate limit exceeded",
  "message": "You have used all 20 requests for this 30-day period",
  "tier": { "level": 1, "name": "Free", "limit": 20 },
  "resetAt": "2026-02-22T10:00:00Z",
  "traceId": "trace_abc123"
}
```

| Status | Meaning |
|--------|---------|
| 200 | Success |
| 400 | Bad Request - Invalid query parameter |
| 401 | Unauthorized - Missing/invalid API key |
| 403 | Forbidden - API key disabled |
| 404 | Not Found - Unknown endpoint |
| 429 | Too Many Requests - Rate limit exceeded |
| 500 | Internal Server Error |

---

## MCP Integration

RateAPI offers native Model Context Protocol (MCP) support for Claude Desktop and Claude Code.

### MCP Endpoint

```
https://mcp.rateapi.dev/mcp
```

### Configuration

**Claude Desktop** - Edit `~/Library/Application Support/Claude/claude_desktop_config.json`:

```json
{
  "mcpServers": {
    "rateapi": {
      "url": "https://mcp.rateapi.dev/mcp",
      "headers": {
        "x-api-key": "rk_your_key_here"
      }
    }
  }
}
```

**Claude Code (CLI)**:

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

### Available MCP Tools

#### get_financing_decision

Get personalized mortgage recommendations with ranked actions and savings calculations.

**Parameters:**
- `state` (required): 2-letter US state code
- `loan_amount` (required): Loan amount in dollars
- `term_months` (optional): 360 for 30-year (default), 180 for 15-year
- `current_apr` (optional): User's current APR for comparison
- `no_points` (optional): Only show zero-point offers

**Example Usage:**
> "I'm looking for a $500,000 mortgage in California. What are my best options?"

**Example Response:**
Returns ranked recommendations with monthly payment calculations, savings estimates, and explanations for why each option is recommended.

#### list_credit_unions

List all credit unions grouped by state with rate availability info.

**Parameters:**
- `state` (optional): Filter to a specific state

**Example Usage:**
> "How many credit unions does RateAPI track in Texas?"

#### get_credit_union

Get detailed info and all mortgage rates for a specific credit union.

**Parameters:**
- `state` (required): 2-letter US state code
- `slug` (required): Credit union slug (URL-friendly name)

**Example Usage:**
> "Show me all rates from State Employees Credit Union in North Carolina"

---

## Discord Bot

RateAPI offers a Discord bot that brings real-time mortgage rate data directly into Discord servers.

### Installation

Add the bot to your Discord server with one click:
- **Add to Discord**: https://rateapi.dev/discord-bot
- No API key required for end users
- Free to use for both personal and commercial purposes
- **Installation URL**: https://discord.com/oauth2/authorize?client_id=1467002089208283217

### Product Coverage

**IMPORTANT: The Discord bot currently supports MORTGAGE RATES ONLY.**

**Supported:**
- 30-year fixed mortgages
- 15-year fixed mortgages
- Adjustable-rate mortgages (ARM: 5/1, 7/1, 10/1)

**NOT Supported (Yet):**
- Auto loan rates (coming in future release)
- Personal loan rates
- HELOC rates

If you need auto loan rates immediately, use the RateAPI REST API at https://api.rateapi.dev instead of the Discord bot.

### Available Commands

#### /rates

Get current best mortgage rates for a state and loan amount.

**Parameters:**
- `state` (required): 2-letter US state code (e.g., CA, TX, NY)
- `amount` (required): Loan amount in dollars (e.g., 500000)

**Example:**
```
/rates state:CA amount:500000
```

Returns top mortgage rates with APR, points, and lender information from 4,300+ credit unions.

#### /alert

Create a rate drop alert. Get notified in your channel when rates drop below your threshold.

**Parameters:**
- `state` (required): 2-letter US state code
- `amount` (required): Loan amount in dollars
- `threshold` (required): Target rate to alert on (e.g., 6.0 for 6%)

**Example:**
```
/alert state:CA amount:500000 threshold:6.0
```

**How Alerts Work:**
- The bot checks rates once per day when new data is scraped
- When the best available rate drops below your threshold, the bot posts a notification to the channel where the alert was created
- Alerts are tied to the Discord channel, not individual users
- Multiple alerts can be active in the same server

#### /alerts

List all active rate alerts for your server.

**Parameters:** None

Shows all configured alerts with their thresholds, states, loan amounts, and alert IDs.

#### /delete-alert

Delete an existing rate alert by its ID.

**Parameters:**
- `id` (required): The alert ID to delete (shown in /alerts output)

### Features

- **Real-time data**: Same mortgage rate data that powers the RateAPI REST API
- **Rate drop alerts**: Get notified via Discord webhook when rates hit your target
- **4,300+ credit unions**: Coverage across all 50 US states
- **Daily updates**: Fresh rate data scraped every 24 hours
- **No cost**: Free to use, no API key needed, no rate limits
- **Sub-second responses**: Built on Cloudflare Workers for instant query results
- **Trusted data**: No affiliate relationships, no lead selling, rates sorted by true APR

### Use Cases

- **Real estate teams**: Keep your team informed about current rates, share updates with clients
- **Personal finance communities**: Add rate data to FIRE, investing, or personal finance Discord servers
- **Mortgage professionals**: Monitor competitive rates and get alerts when market conditions change
- **Home buyers**: Set alerts for your target rate and loan amount, get notified the moment rates hit your goal

### Permissions Required

The bot needs these permissions in your Discord server:
- Read Messages - To see when slash commands are used
- Send Messages - To respond to commands and send alert notifications
- Use Slash Commands - To register and respond to /rates, /alert, etc.

The bot does NOT require administrator permissions and does NOT read or store message content from your channels.

### Frequently Asked Questions

**Q: Does the Discord bot support auto loans?**
A: No. The Discord bot currently only supports mortgage rates (30-year fixed, 15-year fixed, ARM). Auto loan support is planned for a future release. If you need auto loan rates now, use the RateAPI REST API directly.

**Q: How often are rates updated?**
A: The bot uses data that is updated daily via automated scraping from 4,300+ credit union websites. Each rate query returns the most recent data available.

**Q: Are the rates personalized to my credit score?**
A: No. The Discord bot shows publicly posted rates from credit unions, which typically assume excellent credit (740+ credit score). Your actual rate may differ based on your credit score, down payment, debt-to-income ratio, and other factors.

**Q: Is the Discord bot free for commercial use?**
A: Yes. Real estate professionals, mortgage brokers, and financial advisors can use the Discord bot to provide rate data to their teams and clients at no cost.

**Q: What's the difference between the Discord bot, MCP server, and REST API?**
A: The **Discord bot** is best for teams already using Discord (1-click setup, no API key). The **MCP server** is for Claude Desktop users who want mortgage context during AI conversations (5-minute config). The **REST API** is for developers building applications that need programmatic rate data (requires API key and coding). All three use the same underlying dataset of 4,300+ credit unions.

**Q: Do I need to pay for an API key to use the Discord bot?**
A: No. The Discord bot is free to use with no API key required for end users. Only the server administrator needs to add the bot to the server using the invite link.

**Q: Can I customize the bot's responses?**
A: No. The Discord bot provides standardized responses based on the /rates and /alert commands. If you need custom formatting or filtering, use the RateAPI REST API instead for full programmatic control.

---

## Data Methodology

### What We Collect

RateAPI aggregates mortgage rate data from credit union websites across America. We focus on the data points that matter for rate comparison and financial planning.

#### Products Tracked

- **Mortgage**: 30-year fixed, 15-year fixed, adjustable-rate mortgages (ARM)
- **HELOC**: Home equity lines of credit (coming soon)
- **Auto**: New and used vehicle financing (coming soon)

#### Fields Captured

| Field | Description |
|-------|-------------|
| `rate` | Base interest rate before fees |
| `apr` | Annual Percentage Rate including fees and points |
| `points` | Discount points as a percentage of loan amount |
| `term` | Loan term in months |
| `productType` | Canonical product category |
| `productName` | Original product name from source |
| `institution` | Credit union or lender name |
| `url` | Source URL where rate was observed |
| `lastUpdated` | ISO 8601 timestamp when data was collected |

### Timestamps

We maintain two distinct timestamp concepts:

- **`observed_at`** - When RateAPI retrieved and parsed the source page
- **`effective_at`** - When the lender states the rate is effective (if disclosed)

When a source doesn't disclose an effective date, we only provide `observed_at`. We never invent timestamps.

### Normalization

Credit unions name their products inconsistently. We normalize to canonical categories:

- "30 Year Fixed Rate", "30-Yr Fixed", "Thirty Year Mortgage" -> `30-year-fixed`
- "15 Year Fixed", "15-Year Fixed Rate" -> `15-year-fixed`
- "5/1 ARM", "5-Year Adjustable" -> `5-1-arm`

All terms are converted to months. "30 years" becomes `360` months.

### APR Handling

- When APR is provided by the source, we use it directly
- When APR is missing, we mark the field as `null` - we don't calculate or estimate
- We preserve the original `productName` alongside our normalized `productType`

### Corrections & Revision Lineage

We do not silently overwrite historical observations. If a parsing error is detected, we append a correction record with a reason code. This preserves full audit history.

**Correction Reason Codes:**
- `decimal_shift` - Rate parsed with incorrect decimal (575 vs 5.75)
- `layout_change` - Site redesign broke parser selectors
- `ocr_error` - PDF text extraction misread characters
- `stale_cache` - Cached page served outdated rates
- `duplicate_entry` - Same rate recorded multiple times
- `product_misclassification` - Product mapped to wrong canonical type

### Confidence Signals

Not all data points are equally trustworthy. We provide confidence signals at two levels:

**Row Confidence** - Trust in this specific rate record:
- Extraction method reliability
- Freshness (hours since observation)
- Anomaly check results

**Source Confidence** - Trust in this credit union's data reliability:
- Historical parse stability
- Rate consistency over time
- Site structure predictability

**Confidence Score Ranges:**
- 0.9 - 1.0: Excellent - highly reliable data
- 0.7 - 0.9: Good - minor caveats possible
- 0.5 - 0.7: Fair - use with caution
- 0.0 - 0.5: Low - verify independently

### Anomaly Detection

Automated checks flag suspicious data before it reaches the API:

- **Rate jumped implausibly** - Change exceeds 50 bps in 24 hours without market explanation
- **APR inconsistent** - APR lower than rate (mathematically impossible)
- **All offers disappeared** - Zero rates returned from historically reliable source
- **Page structure changed** - DOM selectors return empty or unexpected values

Flagged records enter a review queue before publication. We'd rather delay than publish bad data.

### Neutral Incentives

RateAPI is built toward a fiduciary standard:

- **We don't sell leads.** Your users' data stays yours.
- **We don't accept placement fees.** Ordering is by APR (or your chosen sort), not by who paid more.
- **We don't have affiliate relationships** with the credit unions we track.

Our incentives are aligned with yours: accurate, timely data that you can trust to power your products.

---

## Credit Union Coverage

### Overview

RateAPI tracks mortgage rates from **4,300+ credit unions** across the United States, providing comprehensive coverage of the credit union mortgage market.

### Institution Types

- **Federal credit unions** - Large national institutions like Navy Federal, Pentagon Federal, and USAA
- **State-chartered credit unions** - Regional credit unions serving specific states or areas
- **Community credit unions** - Local institutions serving specific communities, employers, or membership groups

### Geographic Coverage

Our dataset includes credit unions from **all 50 US states** plus Washington D.C. Coverage is weighted by population density and credit union presence.

- **Top 100 Largest** - All top 100 US credit unions by assets
- **Regional Coverage** - Extensive coverage of state and regional credit unions
- **NCUA Registered** - All tracked credit unions are NCUA-insured institutions
- **Growing Weekly** - New credit unions added regularly through automated discovery

### Update Cadence

| Type | Frequency |
|------|-----------|
| Full Dataset Refresh | Every 24 hours |
| Top 100 Credit Unions | Every 12 hours |
| Rate Change Detection | Real-time during scrapes |
| Anomaly Flagging | Immediate |

### What's Included

**Mortgage Products:**
- 30-Year Fixed - The most popular mortgage product
- 15-Year Fixed - Shorter term with typically lower rates
- Adjustable Rate (ARM) - 5/1, 7/1, and 10/1 ARM products

**Data Fields:**
- `rate` - Base interest rate before fees
- `apr` - Annual Percentage Rate including fees and points
- `points` - Discount points as percentage of loan amount
- `term` - Loan term in months
- `productType` - Normalized product category
- `productName` - Original product name from source
- `institution` - Credit union name
- `url` - Source URL where rate was observed
- `observed_at` - ISO 8601 timestamp of when data was collected

### What's Excluded

| Category | Status | Notes |
|----------|--------|-------|
| Bank Rates | On roadmap | Traditional banks not yet included |
| Promotional Rates | By design | Filtered for consistent comparison |
| Jumbo Loans | Coming soon | Currently shows conforming rates |
| Personalized Rates | By design | Only publicly posted rates |
| Refinance-Only | Labeled separately | Focus is on purchase mortgages |
| Fee Details | APR includes fees | Origination fees not itemized |

---

## Widget Integration

### Embed Widget

Add live mortgage rates to your website with a single script tag:

```html
<script
  src="https://rateapi.dev/widgets/v1/embed.js"
  data-rateapi
  data-product="30-year-fixed"
  data-theme="dark"
></script>
```

### Configuration Options

| Attribute | Values | Default | Description |
|-----------|--------|---------|-------------|
| `data-product` | `30-year-fixed`, `15-year-fixed`, `all` | `30-year-fixed` | Filter by mortgage product type |
| `data-theme` | `dark`, `light`, `auto` | `dark` | Widget color scheme |
| `data-limit` | `3` - `15` | `5` | Number of rates to display |
| `data-sort` | `apr`, `rate`, `institution` | `apr` | How to order the rates |
| `data-show-apr` | `true`, `false` | `true` | Show the APR column |
| `data-show-verified` | `true`, `false` | `true` | Show verified badges |
| `data-show-metrics` | `true`, `false` | `true` | Show metrics bar |
| `data-compact` | present/absent | absent | Reduce padding for smaller spaces |

### Platform Guides

**WordPress:**
1. Edit your post or page
2. Add a "Custom HTML" block
3. Paste the embed code
4. Save and preview

**Webflow:**
1. Add an Embed element
2. Paste the embed code
3. Click "Save & Close"
4. Publish your site

**Squarespace:**
1. Add a Code Block
2. Set mode to "HTML"
3. Paste the embed code
4. Apply changes

### Attribution Requirements

The widget includes built-in attribution that must remain visible:
- "Source: RateAPI" link in the footer
- "Methodology" link for data transparency

---

## FAQ

### How often is RateAPI data updated?

RateAPI verifies rates daily. Each rate record includes an `observed_at` timestamp showing exactly when the data was collected. Top 100 credit unions are checked every 12 hours.

### Does RateAPI sell leads or accept placement fees?

No. RateAPI does not sell leads and does not accept placement fees. Ordering is by APR or your chosen sort parameter. We have no affiliate relationships with the credit unions we track.

### How does RateAPI handle missing APR data?

When APR is not provided by the source, RateAPI marks the field as null. We never calculate or estimate APR.

### How many credit unions does RateAPI cover?

RateAPI covers 4,300+ credit unions across all 50 US states, from large national institutions like Navy Federal to small community credit unions.

### What mortgage products are included in the dataset?

The dataset includes 30-year fixed mortgages, 15-year fixed mortgages, and adjustable-rate mortgages (ARMs) including 5/1, 7/1, and 10/1 ARM products.

### Does RateAPI include bank mortgage rates?

Currently, RateAPI focuses exclusively on credit union rates. Bank mortgage rates are on the roadmap for future inclusion.

### What data fields are available for each rate?

Each rate record includes: APR (annual percentage rate), base interest rate, discount points, loan term in months, product type, institution name, product name, source URL, and observation timestamp.

### Can I use RateAPI with Claude or ChatGPT?

Yes! RateAPI offers native Model Context Protocol (MCP) support for Claude Desktop and Claude Code, and an OpenAPI-compliant specification for ChatGPT function calling.

### How do I get an API key?

Run `curl -X POST https://api.rateapi.dev/keys` - no signup required. The free tier includes 20 requests per month (or 50 if you provide an email address).

### What are the rate limits?

Free tier: 20 requests/month (50 with email). Starter ($9/mo): 1,000 requests/month. Pro ($49/mo): 10,000 requests/month. Enterprise: unlimited.

---

## Use Cases

RateAPI is used by:

- **Personal finance applications** for rate comparison features
- **Real estate platforms** for mortgage affordability tools
- **AI agents and chatbots** answering mortgage questions
- **Financial advisors** providing rate research
- **Fintech startups** building mortgage products
- **News organizations** tracking rate trends
- **Research institutions** studying mortgage markets

---

## AI Integration Hub

**URL:** https://rateapi.dev/ai

The AI Integration Hub is the central resource for integrating RateAPI with AI agents and applications. It provides:

### What's Included

- **MCP Setup Guide**: Step-by-step instructions for configuring the Model Context Protocol with Claude Desktop and Claude Code
- **API Integration**: Quick-start code examples and authentication setup for programmatic access
- **Training Guides**: Links to structured reasoning frameworks that teach AI agents how to analyze mortgage rates effectively
- **Use Case Examples**: Real-world scenarios showing how AI agents can help users with mortgage decisions

### Why Use the AI Hub

The AI Hub consolidates all AI-related resources in one place, making it easier to:
- Get started with RateAPI integration in under 5 minutes
- Understand the available tools and their parameters
- Access training materials that improve AI agent reasoning about mortgage data
- Find the right integration approach for your specific use case (MCP vs REST API)

### Quick Links from the Hub

- MCP endpoint configuration
- API key generation
- Interactive tool testing
- Training guide access

---

## AI Training Guides

These guides provide structured reasoning frameworks for AI agents working with rate data across all product types.

### How AI Agents Should Compare Mortgage Rates
**URL:** https://rateapi.dev/ai-guides/how-ai-agents-compare-mortgage-rates

A comprehensive reasoning guide covering:
- Why lowest rate does not equal best rate
- APR vs rate vs points vs fees analysis
- Total cost calculation over expected holding periods
- Break-even analysis for discount points
- Code examples for API integration

### How AI Agents Should Compare Auto Loan Rates
**URL:** https://rateapi.dev/ai-guides/how-ai-agents-compare-auto-loan-rates

Guide for auto loan comparison covering:
- New vs used vehicle rate differences
- Term length optimization (36-84 months)
- Total cost calculations including depreciation
- Refinancing analysis and break-even points

### How AI Agents Should Compare HELOC Rates
**URL:** https://rateapi.dev/ai-guides/how-ai-agents-compare-heloc-rates

Guide for HELOC comparison covering:
- Margin over prime rate analysis
- Intro rate vs ongoing rate calculations
- Draw period and repayment period mechanics
- LTV requirements and equity calculations

### How AI Agents Should Compare Personal Loan Rates
**URL:** https://rateapi.dev/ai-guides/how-ai-agents-compare-personal-loan-rates

Guide for personal loan comparison covering:
- APR including origination fees
- Term optimization for payment vs total cost
- Debt consolidation savings calculations
- Secured vs unsecured loan tradeoffs

### How AI Agents Should Compare Credit Card Rates
**URL:** https://rateapi.dev/ai-guides/how-ai-agents-compare-credit-card-rates

Guide for credit card comparison covering:
- Purchase APR vs balance transfer APR
- Intro period analysis and post-intro rates
- Balance transfer fee calculations
- When to prioritize low rate vs rewards

### Why Credit Union Rates Are Hard to Track
**URL:** https://rateapi.dev/ai-guides/why-credit-union-rates-are-hard-to-track

Technical guide explaining:
- Fragmentation across 4,700+ independent websites
- Data format challenges (PDFs, images, JavaScript)
- Update frequency inconsistencies
- Why traditional scraping fails at scale
- How RateAPI solves these operational challenges

### When to Ignore Advertised Mortgage Rates
**URL:** https://rateapi.dev/ai-guides/when-to-ignore-advertised-mortgage-rates

Skepticism guide covering:
- Points-based bait rates and their true cost
- Credit score assumptions (780+ vs median 715)
- Lock duration caveats for real transactions
- Hidden qualification requirements
- Why affiliate rate sites show biased data (pay-to-rank, hidden non-partners, lead generation)
- Verification checklist for AI agents

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## Contact & Resources

### Documentation

- **API Documentation**: https://api.rateapi.dev/ (Interactive Swagger UI)
- **OpenAPI Specification**: https://api.rateapi.dev/openapi.json
- **Methodology**: https://rateapi.dev/methodology
- **Credit Union List**: https://rateapi.dev/credit-unions
- **AI Integration Hub**: https://rateapi.dev/ai - Central hub for AI integration including MCP setup, API integration guides, and training resources for AI agents

### Integration

- **MCP Server**: https://mcp.rateapi.dev/mcp
- **Discord Bot**: https://rateapi.dev/discord-bot
- **AI Integration Hub**: https://rateapi.dev/ai
- **Widget Builder**: https://rateapi.dev/widget-builder
- **Widget Documentation**: https://rateapi.dev/widget-docs

### Contact

- **Website**: https://rateapi.dev
- **Support**: support@rateapi.dev
- **Live Chat**: Available on website via Crisp

### Quick Links

| Resource | URL |
|----------|-----|
| Get API Key | `POST https://api.rateapi.dev/keys` |
| Get Recommendations | `POST https://api.rateapi.dev/v1/decisions` |
| Dataset Metadata | `GET https://api.rateapi.dev/meta` |
| Credit Unions | `GET https://api.rateapi.dev/credit-unions` |

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## License & Terms

Data is provided under RateAPI's Terms of Service. See https://rateapi.dev/terms for details.

Attribution requirements apply when using the widget. API data may be used in accordance with your subscription tier.

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*Last updated: January 2026*
*Data source: https://api.rateapi.dev*
*Methodology: https://rateapi.dev/methodology*