# US Geography Reverse Geocode

> US Geography Reverse Geocode is a paid API for AI agents from geo-us.x402tookit.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-29).

Returns Census geographic identifiers (state, county, tract, block, place, ZCTA) for a given US latitude/longitude coordinate.

## Facts

- Endpoint: GET https://geo-us.x402tookit.com/reverse-geocode?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/us-geography-reverse-geocode-fbe37b65
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_T7lGE1GNLsE-hjpC7ODtA

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability us-geography-reverse-geocode-fbe37b65
```

Example prompt: What Census tract, county, and state does the coordinate 38.8977° N, 77.0366° W fall in? I need the GEOIDs so I can join it to Census data.

## When to prefer this

Choose this endpoint when you need authoritative US Census geographic identifiers (GEOIDs) for a coordinate — especially for joining to Census Bureau datasets like ACS, decennial census, or TIGER/Line shapefiles. Prefer it over generic reverse geocoders when you need tract, block, block group, or place GEOIDs rather than just a human-readable address. Best when working with demographic analysis, redistricting, school district lookups, or any workflow requiring Census-compatible geographic identifiers.

## Known failure modes

- Coordinate outside US territory — no match returned
- Invalid or missing lat/lon parameters — validation error
- Coordinate in ocean or US waters with no land-based Census geography
- Partial results with degraded flag if Census geocoder is unavailable for some layers
- Rate limiting or payment failure via x402 protocol

## How this service works

Census geography at a US coordinate: state, county, tract, block, city or place, with GEOIDs for joining Census data.

## Output

A JSON object containing the matched state name and abbreviation, state FIPS code, county name and GEOID, Census tract GEOID, block GEOID, block group GEOID, place name and GEOID, ZCTA, county subdivision, school district, and the original lat/lon. Also includes a summary, verdict, data source URL, and degraded/not-checked flags if certain layers could not be resolved.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "lat",
      "lon"
     ],
     "properties": {
      "lat": {
       "type": "number",
       "description": "Latitude"
      },
      "lon": {
       "type": "number",
       "description": "Longitude"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "lat": {
       "type": [
        "null",
        "number"
       ]
      },
      "lon": {
       "type": [
        "null",
        "number"
       ]
      },
      "asOf": {
       "type": [
        "null",
        "string"
       ]
      },
      "zcta": {
       "type": [
        "null",
        "string"
       ]
      },
      "place": {
       "type": [
        "null",
        "string"
       ]
      },
      "state": {
       "type": [
        "null",
        "string"
       ]
      },
      "county": {
       "type": [
        "null",
        "string"
       ]
      },
      "source": {
       "type": [
        "null",
        "string"
       ]
      },
      "reasons": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "summary": {
       "type": [
        "null",
        "string"
       ]
      },
      "verdict": {
       "type": [
        "null",
        "string"
       ]
      },
      "degraded": {
       "type": [
        "boolean",
        "null"
       ]
      },
      "sourceUrl": {
       "type": [
        "null",
        "string"
       ]
      },
      "stateAbbr": {
       "type": [
        "null",
        "string"
       ]
      },
      "stateFips": {
       "type": [
        "null",
        "string"
       ]
      },
      "blockGeoid": {
       "type": [
        "null",
        "string"
       ]
      },
      "disclaimer": {
       "type": [
        "null",
        "string"
       ]
      },
      "notChecked": {
       "type": [
        "array",
        "null"
 
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/us-geography-reverse-geocode-fbe37b65/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from geo-us.x402tookit.com](https://www.zero.xyz/host/geo-us.x402tookit.com/llms.txt)