Real Estate API Questions

How do I query county parcel data by API?

Quick Answer

To query county parcel data by API, send an HTTP GET request to Realie’s property endpoints with your target state, county, parcel ID (APN), or street address, authenticated with a Bearer API key. You receive normalized JSON containing parcel boundaries, owner records, assessor valuations, sale history, and zoning across 3,100+ U.S. counties.

Summary

Querying county parcel data traditionally required navigating thousands of separate county assessor and recorder portals, each with different parcel identifier (APN) formats and data schemas. A property data API resolves that fragmentation into a single endpoint. You pass a parcel ID, street address, or geographic coordinates and get back standardized JSON in sub-10 milliseconds. For coding agents and CLI workflows, Realie also provides a command-line tool and an MCP server for direct IDE querying in Claude and Cursor.

Querying by State, County, and Parcel ID (APN)

The most direct lookup is by Assessor Parcel Number (APN). Because APN formats vary across counties (some use dashes, others use leading zeroes), Realie normalizes parcel identifiers while preserving the raw county APN in the payload. To query, pass the state, county name, and parcel ID to the `/api/public/property/parcelId` endpoint.

The API returns parcel boundary polygons, land square footage, building area, current assessed value, tax status, and legal description in a single payload.

Querying by Address or Location Radius

If you do not have the exact APN, you can query by street address or geographic location coordinates. Address lookups (`/api/public/property/address`) parse and standardize street lines against county tax rolls. Location lookups (`/api/public/property/location`) use spatial indexing to return parcel records near latitude and longitude coordinates within a specified radius.

Each property search request returns up to 100 properties per response page, allowing applications to retrieve comprehensive parcel records efficiently with sub-10 millisecond average response times.

CLI and AI Agent Workflows (MCP)

Developers and AI agents do not need to write raw HTTP requests manually. The Realie CLI provides terminal-native lookups with `--json` output for shell scripts. For AI coding assistants like Claude Code, Cursor, and VS Code, the Realie MCP server enables agents to fetch county parcel records directly during code generation.

Frequently asked questions

What parameters are required to query by parcel ID?
You need the state, county name, and the county parcel identifier (APN). Realie handles formatting and hyphen variations automatically.
Does the API return parcel boundary polygons?
Yes. Parcel boundary geometry is returned alongside building, owner, tax, and zoning attributes in the same JSON object.
Can AI agents query county parcel data directly?
Yes. Realie provides an MCP server and an `agents.md` discovery spec so AI coding assistants (Claude, Cursor, Codex) can discover and query parcel endpoints automatically.
How fast are parcel API responses?
Realie’s published average API response latency is 9.49 ms, designed for live interactive map and search applications.