Census Geocoder MCP server

@pipeworx/census-geocoder

The US Census Bureau's own geocoder: turns a US street address into a TIGER/Line coordinate and the full Census geography stack for that point — state, county, census tract, census block, place, congressional district, school district and CBSA, each with its GEOID.

Part of Pipeworx — an MCP gateway connecting AI agents to 1679+ live data sources.

Tools

forward geocode one address; returns coordinates plus the geography stack.

• censusgeocodeaddress(address | street/city/state/zip, benchmark?, vintage?) —

Census geography containing a coordinate.

• censusreversegeocode(latitude, longitude, benchmark?, vintage?) — every

addresses in one call; returns match status, standardized address, coordinates and state/county/tract/block FIPS per row, plus the assembled tract and block GEOIDs.

• censusgeocodebatch(addresses[], benchmark?, vintage?) — up to 100

Auth

Keyless.

Data sources

• — one-line forward geocode.
• — structured forward geocode.
• — reverse geocode.
• — multipart CSV batch.

Related packs: census-tigerweb describes the geographies themselves (list every tract in a county); this pack answers "which tract is this address in". The geocodio pack is a commercial geocoder and is not a substitute when the answer has to be a Census GEOID.

Traps

Current_Current; a mismatched pair is a 400 with an unhelpful body.

• benchmark and vintage must agree. PublicARCurrent pairs with

return only coordinates. This pack always uses /geographies.

• The /geographies/ endpoints return geography; the /locations/ ones

geocodes every line it is handed. Send a header row and you get a No_Match result for the literal word "street". This pack never sends one.

• The batch endpoint is a multipart CSV POST that answers in CSV, and it

comma inside a street field shifts every later column. Each cell is quoted.

• Batch columns are positional (id,street,city,state,zip) so an unquoted

they are matched by pattern rather than by a name that expires.

• Congressional and state-legislative layer names carry the session number, so

Quick Start

Add to your MCP client (Claude Desktop, Cursor, Windsurf, etc.):

{
  "mcpServers": {
    "census-geocoder": {
      "url": "https://gateway.pipeworx.io/census-geocoder/mcp"
    }
  }
}

What this endpoint actually serves

tools/list at https://gateway.pipeworx.io/census-geocoder/mcp returns the tools in the table above plus the shared Pipeworx meta-tools — askpipeworx, discovertools, search_within, remember/recall and the rest of the gateway-wide set. So the tool count you see is larger than this table: a single-pack endpoint currently lists roughly 30 shared tools alongside the pack's own. The connection's initialize response states its exact scope, and is the authoritative answer for a given day.

This is deliberate, not multiplexing by accident. The meta-tools are what let a scoped connection answer a question this pack does not cover — via ask_pipeworx, which routes across the whole catalog — without you adding a second MCP server. There is currently no way to mount a pack endpoint without them; if the extra schemas cost you more context than the routing is worth, connect to the full gateway once rather than to several pack endpoints.

Or connect to the full Pipeworx gateway to get every pack's tools listed directly, instead of just this one's:

{
  "mcpServers": {
    "pipeworx": {
      "url": "https://gateway.pipeworx.io/mcp"
    }
  }
}

Shortened. The full README is on GitHub.