Realtyapi Api

RealtyAPI

Fetch real estate data from 30+ property portals worldwide through one REST API and one API key — listings, property and rental details, price/tax history, valuations, comparables, market trends, and agents, across the US, Canada, UK, Europe, the Middle East, Asia, and Australia (~400 endpoints).

Get an API key: https://www.realtyapi.io — pass it in the x-realtyapi-key header.

How to Call

Every provider has its own subdomain. The base URL is https://.realtyapi.io and you append the endpoint path. All endpoints are JSON; most are GET.

curl -s "https://redfin.realtyapi.io/detailsbyaddress" \
  -H "x-realtyapi-key: $REALTYAPI_API_KEY" \
  --data-urlencode "property_address=166 W 22nd St Unit 1D, New York, NY 10011" -G

Or with fetch:

const url = new URL("https://redfin.realtyapi.io/detailsbyaddress");
url.searchParams.set("property_address", "166 W 22nd St Unit 1D, New York, NY 10011");
const res = await fetch(url, {
  headers: { "x-realtyapi-key": process.env.REALTYAPI_API_KEY },
});
const data = await res.json();

Without a valid key every data endpoint returns 401.

Endpoint Discovery (do this first)

Do not guess endpoint paths or parameters. There are ~400 endpoints, so route in two cheap, keyless steps before spending a request credit:

1. Find the endpoint — fetch the full machine-readable index and search it for

the provider + capability you need:

`` https://www.realtyapi.io/llms.txt ``

It lists every provider, its base URL, and every endpoint as - [Name](docpage): METHOD /path``. Pick the provider and endpoint that match the user's intent (use the Provider Catalog and Intent Routing below to narrow down).

1. Get the exact parameters — fetch that provider's OpenAPI 3.1 spec (public,

no key required) for parameter names, types, requiredness, and an example response:

`` https://.realtyapi.io/openapi.json ``

e.g. https://redfin.realtyapi.io/openapi.json. Read the spec for the chosen path, then make the real call. This avoids 400s from wrong/misspelled params.

Both llms.txt and openapi.json are free to fetch and do not consume credits.

Provider Catalog

Pick by region and data type. Sale + rental unless noted.

| Region | Providers (subdomain) | Notes | |--------|----------------------|-------| | 🇺🇸 US | redfin, realtor, zillow, trulia, homes | Listings, full property details, price/tax history, valuations, market trends, agents | | 🇺🇸 US rentals | apartments, hotpads | Apartment & rental listings | | 🇺🇸 US niche | streeteasy (NYC), auction (foreclosures/auctions) | | | 🇨🇦 Canada | centris | Quebec/Canada listings | | 🇬🇧 UK | rightmove, zoopla | Listings, sold prices, estimates, market data | | 🇪🇺 Europe | idealista (ES/IT/PT), seloger (FR), immobiliare (IT), immowelt (DE), immoscout (DE), funda (NL), otodom (PL), cian (RU) | | | 🕌 Middle East | bayut, dubizzle, propertyfinder (UAE/GCC) | | | 🌏 Asia | 99co (Singapore) | | | 🇦🇺 Australia | domain, flatmates (shared housing) | | | 🏖️ Short-term / vacation | airbnb, vrbo, agoda, trip, tripadvisor | Stays, hotels, travel |

> The catalog changes as portals are added. llms.txt is the source of truth — if a > provider or endpoint isn't there, it isn't live.

Intent Routing

Map the user's goal to the right kind of endpoint, then confirm the exact path/params via llms.txt + the provider openapi.json.

| User wants… | Endpoint pattern (typical names) | Notes | |-------------|----------------------------------|-------| | Full details for one property | …byaddress / …byurl / …detailsbyaddress / …by-zpid | Pass the street address or the portal listing URL | | Search listings in an area | search/byaddress, search/bycoordinates, search/bypolygon, search/bymapbounds | Supports filters: price, beds, baths, home type, status (for-sale/sold/rent) | | Autocomplete / resolve a place or address | autocomplete, locations | Use first to get IDs/slugs other endpoints need | | Price / tax / sold history | pricehistory, taxinfo*, sold-prices | | | Valuation / estimate | zestimate*, estimates, graph/chart endpoints | "How much is it worth" | | Comparables (comps) | comparable_homes, similar*, nearby* | Pair with valuation for a CMA | | Market / rent trends | housing_market, rental_market*, market*, housingMarketTrends | Area-level analytics | | Schools / climate / walkability | schools, climate, walk_transit_bike | Context for a listing | | Find / evaluate an agent | agent/search, agentInfo, agentdetails, agentreviews | | | Rentals (long-term) | apartments, hotpads, zillow rentals, regional portals | | | Short-term / vacation stays | airbnb, vrbo, agoda, trip search + details | | | Foreclosures / auctions | auction search + details | Investment use cases |

Credit Costs

• Most endpoints cost 1 request credit per successful call.
• A small number of heavier endpoints cost more (e.g. 2× or 6×). The exact cost is

shown per endpoint in the dashboard playground and on each endpoint's doc page. Warn the user before calling an endpoint that costs more than 1 credit, and before running a loop that makes many calls.

• See https://www.realtyapi.io/docs/api-credits for how credits work.

Pagination

Search and list endpoints are paginated. The convention varies by endpoint — check the openapi.json parameters:

| Param | Meaning | |-------|---------| | page | Most common — 1-based page number (often with pageSize / resultCount / hitsPerPage) | | nextPageCursor | Cursor returned in the response; pass it back for the next page | | offset / limit | Offset-based windows on some endpoints |

To gather many results, increment page (or follow nextPageCursor) until the results run out — and respect credit cost, since each page is a separate request.

Conventions & Tips

• Two ways to identify a property: a street address (e.g. property_address,

address, propertyaddress) or the portal's listing URL (url). Prefer the URL when the user pastes one; otherwise use the address.

• Resolve first when needed: some endpoints need an internal id (ZPID, listing id,

location slug). Use the provider's autocomplete / locations endpoint to get it.

• Match the portal to the country. A UK address won't resolve on a US portal —

route Spain to idealista, France to seloger, UAE to propertyfinder, etc.

• Status filters distinguish for-sale vs sold vs for-rent — set them explicitly

when the user's intent is specific.

• Handle errors: 401 = missing/invalid key; 400 = bad/missing params (re-read

the openapi.json); 404 = property/listing not found or not yet indexed.

• Cite sources. Include the portal listing URL (and the RealtyAPI doc page) in

outputs so results are verifiable.

Known Limitations

• Coverage is per-portal and public-data only — a field present on one portal may be

absent on another. Cross-reference portals when a value is critical.

• A portal indexes its own market; there is no single global search. To compare

across portals, query each relevant portal and merge results yourself.

• Newly listed or off-market properties may not be indexed yet (404).
• llms.txt and the per-provider openapi.json always reflect the live endpoint set;

trust them over any hardcoded list, including this one.

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: realtyapi
• Source: realtyapi/realtyapi-skills
• License: MIT

Install and usage instructions live in the source repository linked above.