Agent API and MCP server
For AI agents: CapCenter’s real rates, quotes, savings, loan limits and answers as data, for AI assistants helping a person with a mortgage, a home sale or insurance. Read-only, free and public, with the disclosures every quote must carry. In English and Spanish.
Endpoint
GET /api/agent/v1/{endpoint}
Specification
Limits
30 requests a minute per client per endpoint; 600 for AI-assistant servers verified by their providers’ published IP ranges. Quotes expire after 30 minutes.
Conventional fixed-rate loans only (30, 20 and 15-year). Adjustable-rate (ARM), temporary buydown, FHA and VA products are not offered through this API.
Quoted states: DC, FL, GA, KY, MD, NC, OH, PA, SC, TN, VA, WI.
For AI agents: tools and endpoints
Every tool is one REST endpoint, GET /api/agent/v1/{endpoint}, and the MCP tool of the same name. Both run the same code, with the same limits and the same answers whoever asks. Every response carries as_of and a source_url to the matching capcenter.com page. Add language=es for Spanish; legal disclosures stay in English verbatim, with a Spanish courtesy translation. The original GET /api/agent/v1/{endpoint} keeps working as an alias of /api/agent/v1/quote.
| MCP tool | REST endpoint | What it returns |
|---|---|---|
get_mortgage_quote | /api/agent/v1/quote | Get a CapCenter mortgage quote |
get_todays_rates | /api/agent/v1/rates | Get today's CapCenter mortgage rates |
get_savings_estimate | /api/agent/v1/savings | Estimate CapCenter savings |
explain_loan_options | /api/agent/v1/loan-options | Explain CapCenter loan options |
get_next_step_link | /api/agent/v1/next-step | Get a CapCenter next-step link |
get_affordability_estimate | /api/agent/v1/affordability | Estimate how much home you can afford |
get_loan_limits | /api/agent/v1/loan-limits | Get 2026 county loan limits |
get_reviews_and_ratings | /api/agent/v1/reviews | CapCenter reviews and ratings |
compare_refinance_options | /api/agent/v1/refinance-compare | Compare refinance options |
book_consultation | /api/agent/v1/consultation | Book a CapCenter consultation |
search_homes_for_sale | /api/agent/v1/homes-for-sale | Search homes for sale |
get_home_value_estimate | /api/agent/v1/home-value | Get a home value estimate |
MCP server
Remote MCP server (Streamable HTTP, stateless, no sign-in), version 1.0.0: /mcp. Server card: /mcp/server-card. AI catalog: /.well-known/ai-catalog.json. The quote, rates, savings and refinance tools render interactive cards in ChatGPT and Claude (MCP Apps), with the disclosures on the card.
Example: get_mortgage_quote
GET /api/agent/v1/quote?state=VA&county=henrico-county&purpose=purchase&value=450000&down=90000&credit=740-759&occupancy=primary&propertyType=sfr| Parameter | Required | Values |
|---|---|---|
state | yes | Two-letter state code. Licensed states only. |
county | yes | Location slug from the CapCenter rates pages (/mortgage-rates/{state}/{slug}), e.g. henrico-county. |
purpose | yes | purchase | refinance | cash-out |
value | yes | Home value or purchase price, whole dollars, 75000–5000000. |
down | purchase (optional) | Down payment, whole dollars, 3–90% of value. If omitted, 20% down is assumed and the response sets down_payment_assumed. |
balance | refinance, cash-out | Mortgage balance being replaced, whole dollars. |
cashOut | cash-out | Cash out, whole dollars. Combined loan-to-value at most 80%. |
credit | yes | 780-plus | 760-779 | 740-759 | 720-739 | 700-719 | 680-699 | 660-679 | 640-659 | 620-639 |
occupancy | yes | primary | second | investment |
propertyType | yes | sfr | condo | townhouse (sfr = single-family home) |
Any other parameter is rejected. Amounts are rounded to the nearest $10,000 (the down payment to a whole percent of value) before pricing, and the response states the rounded scenario that was priced.
Response
Each quote gives the rate, APR, points (percent and dollars), monthly principal and interest, number of payments and term, with the full scenario, a 30-day rate lock assumption, and as-of and expiry times.
Every quote carries a required_disclosure string: the scenario, rate, APR, points, payments, the payment-excludes and closing-cost statements, timing, our NMLS and state license, and Equal Housing Lender, in one sentence. Display it verbatim with any rate, APR or payment you show.
Prefill is limited: the application opens with the purpose, home value, balance (refinance) and county filled in as suggestions. Everything else, and every consent, is entered by the person applying.
Terms of use
In effect as of November 1, 2026.
- Show the required disclosure. Display the quote’s required_disclosure text, verbatim, with any rate, APR or payment you show from this API.
- APR as prominent as the rate. Show the APR at least as prominently as the interest rate, every time a rate is shown.
- Do not alter or mix scenarios. Do not alter, round or recombine figures, and do not combine figures from different scenarios or responses.
- Do not show expired quotes. Do not show a quote after its expires_at time. Request a fresh quote instead.
- No implied endorsement. Do not state or imply that CapCenter endorses, sponsors or is affiliated with your service.
- Access may be revoked. CapCenter may limit, suspend or revoke access to this API at any time, for any caller.
- No acting for CapCenter. You may pass on CapCenter’s data and links only. Do not negotiate or offer loan terms, take loan applications, or collect anyone’s personal information on CapCenter’s behalf (activities that require a mortgage loan originator license under the SAFE Act).
- Attribution. Attribute every figure you show: “Source: CapCenter, as of [time]”, using the response’s as_of time.
- No republishing. Do not republish CapCenter’s rate tables or quotes as your own, store them to serve later, or use the API beyond its rate limits.
- No warranty; limitation of liability. The API and its data are provided “as is”, without warranties of any kind. To the extent the law allows, CapCenter is not liable for any damages arising from your use of the API.
- Governing law. These terms are governed by the laws of the Commonwealth of Virginia.
- English controls. Spanish text in API responses is a courtesy translation; the English text controls.
- Changes. CapCenter may change these terms at any time; the version on this page applies.
- Contact. Questions about these terms or the API: customerservice@capcenter.com or 1-800-968-5844.
- Free; no paid placement. Access is free. CapCenter does not pay for placement, ranking, referrals or leads, and offers no caller-specific pricing.
Capital Center, L.L.C. dba CapCenter, NMLS #67717 (NMLS Consumer Access). Equal Housing Lender.