geo.flood-zone

Determine the FEMA flood zone for a coordinate. Pass lat and lon. Returns the FEMA flood zone code (e.g. AE, VE, X), its subtype, whether the point is in a Special Flood Hazard Area (isSFHA — the 1% annual-chance floodplain where flood insurance is mandatory for federally backed mortgages), a plain-language risk level (high / moderate / minimal / undetermined / unmapped) and description, the static base flood elevation and depth when published, and the source FIRM panel id. Data: FEMA National Flood Hazard Layer (NFHL), free and public-domain. When no flood polygon intersects the point, returns mapped=false (usually Zone X / minimal risk or unmapped — not a guarantee of zero risk). Use for property risk screening, insurance/mortgage context, and siting decisions; geocode an address with /api/geocode/address first to get the coordinate.

price
$0.0014 USDC per call
method
GET/api/geo/flood-zone
payment
x402 v2 · USDC on Base (EIP-3009) or Solana (SPL transfer)
auth
None. Sign the payment, retry with PAYMENT-SIGNATURE.
tier
Tier 0 — no paid upstream

Parameters

NameTypeDescription
latrequirednumber
min -90 · max 90
lonrequirednumber
min -180 · max 180

Code samples

cURLbash
# 1. Probe with no auth → 402 envelope with PaymentRequirements
curl -sS 'https://2s.io/api/geo/flood-zone?lat=-90&lon=-180'

# 2. Sign + retry with PAYMENT-SIGNATURE:
curl -sS 'https://2s.io/api/geo/flood-zone?lat=-90&lon=-180' \
  -H 'PAYMENT-SIGNATURE: <base64-json-payload>'

# Or use the canonical runner (handles probe → sign → retry):
#   EVM_PRIVATE_KEY=0x... node --env-file=.env.local \
#     --experimental-strip-types scripts/x402-pay.ts \
#     'https://2s.io/api/geo/flood-zone?lat=-90&lon=-180'
TypeScript / Node — @2sio/sdktypescript
import { TwoS } from '@2sio/sdk'

const client = new TwoS({
  privateKey: process.env.EVM_PRIVATE_KEY as `0x${string}`,
})

const result = await client.geo.floodZone({
  "lat": -90,
  "lon": -180
})

console.log('endpoint:', result.endpoint)
console.log('cost:', result.costUsd, 'USDC')
console.log('tx:', result.settlement?.txHash)
console.log('data:', result.data)
Python — 2siopython
import os
from twosio import TwoS

client = TwoS(private_key=os.environ["EVM_PRIVATE_KEY"])

result = client.geo.flood_zone(lat=-90, lon=-180)

print("endpoint:", result.endpoint)
print("cost:", result.cost_usd, "USDC")
print("tx:", (result.settlement or {}).get("tx_hash"))
print("data:", result.data)
MCP — Claude Desktop / AgentKit / any MCP hostjson
// 1. Add @2sio/mcp to your MCP host config (Claude Desktop example below).
//    EVM_PRIVATE_KEY funds x402 payments per call.

// claude_desktop_config.json
{
  "mcpServers": {
    "2sio": {
      "command": "npx",
      "args": ["-y", "@2sio/mcp"],
      "env": { "EVM_PRIVATE_KEY": "0x..." }
    }
  }
}

// 2. Once the server is running, agents call this tool via standard MCP:

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "geo.flood-zone",
    "arguments": {
      "lat": -90,
      "lon": -180
    }
  }
}

Response

FieldTypeDescription
queryobject
mappedboolean
floodZonestring
zoneSubtypestring
isSFHAboolean
riskLevelstring
one of: high | moderate | minimal | undetermined | unmapped
zoneDescriptionstring
staticBFEnumber
depthnumber
firmPanelIdstring
sourceCitationstring
notestring
sourcesarray
Example response datajson
{
  "query": {
    "lat": 1,
    "lon": 1
  },
  "mapped": false,
  "floodZone": "example",
  "zoneSubtype": "example",
  "isSFHA": false,
  "riskLevel": "high",
  "zoneDescription": "example",
  "staticBFE": 1,
  "depth": 1,
  "firmPanelId": "example",
  "sourceCitation": "example",
  "note": "example",
  "sources": [
    {
      "provider": "example",
      "url": "example",
      "license": "example"
    }
  ]
}

Discovery

2s.io is x402-native. Every call is paid per-request from a USDC-funded EVM wallet on Base — no signup, no API keys, no monthly fees. Source code: github.com/2s-io/sdk.