Owner and APN lookup across 171 verified US county parcel ArcGIS endpoints. No API key needed.
@urbankitstudio/mcp-atlas
This MCP server queries 155 verified US county parcel ArcGIS REST endpoints to support owner/APN and address lookup. It provides AI assistants direct access to UrbanKit Studio’s atlas of manually verified county parcel GIS services using the Model Context Protocol (MCP), without requiring an API key.
🛠️ Key Features
Queries 155 verified US county parcel ArcGIS REST endpoints
Owner/APN lookup support via ArcGIS REST endpoints
Address lookup support via ArcGIS REST endpoints
No API key required
🚀 Use Cases
Find the correct ArcGIS REST endpoint for a covered county
Retrieve the exact owner-search query URL
Look up parcel data by owner, APN, or address
⚡ Developer Benefits
Developer access to an atlas of manually verified county parcel GIS services
Endpoint discovery for covered counties through MCP
Consistent owner-search query URL retrieval
⚠️ Limitations
Covers only the 155 verified US counties included in the atlas
Query the parcel ArcGIS REST endpoints of 277 counties across 51 US states (50 states plus DC), 288 endpoints total, for owner, APN and address lookup via the Model Context Protocol (MCP).
An MCP server that gives AI assistants direct access to UrbanKit Studio's atlas of manually verified county parcel GIS services. Ask Claude or Cursor to find the ArcGIS REST endpoint for any covered county, get the exact owner-search query URL, and look up parcel data — without needing to know anything about ArcGIS REST API conventions.
Coverage: 277 counties across 51 US states (50 states plus DC), 288 endpoints, 287 of them live (atlas 0.6.23).
Quick start
Claude Desktop
Add to ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows):
Then use mcp-atlas as the command instead of npx -y @urbankitstudio/mcp-atlas.
Tools
The four tools are one pipeline, and what separates them is how precisely you
can already name the county:
You have
Use
You get
A state, or nothing
list_counties
Which counties are covered, and whether owner search works there. No URLs.
A vague, misspelled or FIPS reference
find_county
Every county that reference matches, named, each with its record
An exact state and county
get_parcel_endpoint
That one county's endpoint URL, layer, fields and sample query
A county and an owner's name
build_owner_query
A runnable URL that searches for that name
find_county and get_parcel_endpoint return the same per-county record. They
differ in how you address the county: find_county accepts an uncertain
reference and may come back with several candidates, get_parcel_endpoint
takes an exact pair and answers about one. If you already know the county, skip
find_county.
This server never executes a query and returns no parcel records. It tells you
the URL to fetch; fetching it is yours to do.
list_counties
Browse coverage. Answers "is this county covered?" and "what can I search
there?" — one line per county, with no endpoint URLs or field names.
Parameter
Type
Required
Description
state
string
No
Two-letter abbreviation (IL) or full name (Illinois)
Example prompt: "List all covered counties in Illinois"
Example output:
code
ST | County | Slug | Coverage
--------------------------------------------------------------------
IL | Kane | kane-county | owner+APN
IL | Cook | cook-county | APN only
IL | DuPage | dupage-county | owner+APN
...
What each Coverage label promises:
Label
Meaning
owner+APN
build_owner_query returns a URL for at least one endpoint
APN only (county publishes no owner name)
A reviewed record says the county serves no usable owner name
location queries only
No endpoint answers attribute searches; parcels are reached by geometry, which also returns owner fields
APN only (owner column not searchable)
An owner column exists but the county marks it unsearchable by name; a parcel-id or location query returns it
APN only
No endpoint documents an owner column
find_county
Resolves a reference you cannot state exactly. Fuzzy-matches a partial or
misspelled name, a "County State" phrase, or a 5-digit FIPS code against every
covered county, and names each county it matched so an ambiguous reference
comes back as a list to choose from. Each match carries that county's record:
endpoint URLs, searchable field names, owner field, sample query, license.
Parameter
Type
Required
Description
query
string
Yes
County name (Kane), name+state (Kane IL), or FIPS (17089)
Example prompt: "Find the parcel endpoint for Kane County Illinois"
get_parcel_endpoint
The default lookup once the county is known. Returns the full ArcGIS REST URL,
layer index, searchable fields, owner field (or why no owner query is offered),
the county's Scope: predicate when the layer is shared statewide or
regionally, a generic sample ?where=…&f=json query and the UrbanKit deep-link
for one county. For a named owner, use
build_owner_query rather than editing the sample query by hand.
Parameter
Type
Required
Description
state
string
Yes
Two-letter abbreviation or full name
county
string
Yes
County name (Kane or Kane County)
Example prompt: "Give me the ArcGIS REST endpoint for Cook County Illinois"
build_owner_query
The only tool that searches for a named owner. Fills a person or company name
into the county's verified owner/taxpayer field as
UPPER(field) LIKE UPPER('%NAME%'), a case-insensitive partial match, and
returns a URL you can fetch or open. On a shared statewide or regional layer
(Connecticut's regional composites, for example) the county's scope predicate
is ANDed in front, as
(scope) AND UPPER(field) LIKE …, so only that county's rows come back.
An endpoint is refused, with the reason, rather than handed a query that finds
nothing or hangs:
a reviewed record says the county publishes no usable owner name;
the layer serves no attribute search at all (query it by location instead);
the owner column is not searchable by name (use a parcel-id or location query).
Parameter
Type
Required
Description
state
string
Yes
Two-letter abbreviation or full name
county
string
Yes
County name
owner_name
string
Yes
Owner/taxpayer name (partial match)
Example prompt: "Build an ArcGIS query for properties owned by 'Smith' in Kane County IL"
Example output:
code
County: Kane, Illinois
Owner field: TaxName
WHERE clause: UPPER(TaxName) LIKE UPPER('%SMITH%')
Query URL:
https://gistech.countyofkane.org/arcgis/rest/services/KanePINList/MapServer/0/query
?where=UPPER(TaxName)%20LIKE%20UPPER('%25SMITH%25')
&outFields=PIN,TaxName,SiteAddress,SiteCity,MailingAddress
&returnGeometry=false&f=json&resultRecordCount=25
Example conversation
User: I'm doing due diligence on properties in Kane County, Illinois. Can you find all parcels owned by "Blackstone"?
Claude (using mcp-atlas):
Calls get_parcel_endpoint → gets the gistech.countyofkane.org URL and confirms the owner field is TaxName
Calls build_owner_query with owner_name=Blackstone → returns a ready fetch URL
Optionally fetches the URL and formats the parcel results
Atlas coverage
The atlas is maintained by UrbanKit Studio. All endpoints are manually verified. Counties with an owner/taxpayer field support full name-based lookups; PIN-only counties support APN/parcel-number queries.
Atlas data is embedded in the package (no network calls at startup). The underlying @urbankitstudio/atlas SDK is also published separately for programmatic use.
What Socket flags, and how much of it is ours
Socket's supply-chain scanner
rates this package in the mid-70s. Clicking through shows a long alert list. Each alert,
checked rather than waved away:
Alert
Whose
What it is
usesEval
Not ours
No eval or new Function anywhere in src/. It comes from a dependency.
unmaintained (21)
Not ours
Transitive dependencies last published 2017–2021.
mixedLicense
Not ours
A dependency published as BSD-3-Clause AND ISC.
noTests
Ours, by design
files ships dist only. The suite lives in test/ and runs in CI. Shipping tests inside the tarball would be the defect.
An MCP server talks to a client over stdio and reads its own config. A server without these could not do the job.
unpopularPackage, noV1
Ours
Download count and a 0.x version. Both resolve with time, neither is a code issue.
Vulnerability and license both come back at 100, quality at 99. The number the
badge shows is the supply-chain sub-score, and its single largest deduction is download
count, a popularity measure wearing a security badge's clothes. Judge the list above, not
the digit.
The four access alerts are what let the server read its own config and talk to a client
over stdio, nothing more. It still never executes a query or returns a parcel record.