nutrition.food

USDA FoodData Central nutrition lookup. Two modes: search (query=cheddar cheese) returns matching foods with fdcId, description, data type, category, and brand; detail (fdcId=328637) returns the full analyzed nutrient profile — energy, protein, fats, carbohydrates, vitamins, minerals — with USDA nutrient numbers, amounts, and units (per 100 g/ml unless serving fields indicate otherwise), plus ingredients for branded foods. Filter search by dataType: Foundation and SR Legacy are lab-analyzed generic foods, Branded is the packaged-food label corpus, Survey (FNDDS) is as-consumed dishes. Authoritative USDA data covering ~400k foods — use real analyzed values instead of model-estimated nutrition facts.

price

$0.0012 USDC per call

method

GET/api/nutrition/food

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

Name	Type	Description
`query`	string	Food name to search, e.g. "cheddar cheese". Provide query or fdcId, not both. min 2 chars · max 120 chars
`fdcId`	integer	FDC food id — returns the full nutrient profile. min 0
`dataType`	string	Restrict search to one data type. Foundation/SR Legacy = analyzed generic foods, Branded = packaged labels, Survey (FNDDS) = as-consumed dishes. one of: Foundation \| SR Legacy \| Survey (FNDDS) \| Branded
`limit`	integer	min 1 · max 50
`page`	integer	min 1

Code samples

cURLbash

# 1. Probe with no auth → 402 envelope with PaymentRequirements
curl -sS 'https://2s.io/api/nutrition/food?query=xx&fdcId=0&dataType=Foundation&limit=10&page=1'

# 2. Sign + retry with PAYMENT-SIGNATURE:
curl -sS 'https://2s.io/api/nutrition/food?query=xx&fdcId=0&dataType=Foundation&limit=10&page=1' \
  -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/nutrition/food?query=xx&fdcId=0&dataType=Foundation&limit=10&page=1'

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.nutrition.food({
  "query": "xx",
  "fdcId": 0,
  "dataType": "Foundation",
  "limit": 10,
  "page": 1
})

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.nutrition.food(query="xx", fdcId=0, dataType="Foundation", limit=10, page=1)

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": "nutrition.food",
    "arguments": {
      "query": "xx",
      "fdcId": 0,
      "dataType": "Foundation",
      "limit": 10,
      "page": 1
    }
  }
}

Response

Field	Type	Description
`mode`	string	one of: search \| detail
`totalHits`	number	Total matches (search mode only).
`foods`	array	Search results (search mode only).
`food`	object	Full nutrient profile (detail mode only). Values per 100 g/ml unless serving fields indicate otherwise.
`source`	object

Example response datajson

{
  "mode": "search",
  "totalHits": 1,
  "foods": [
    {
      "fdcId": 1,
      "description": "example",
      "dataType": "example",
      "foodCategory": "example",
      "brandOwner": "example",
      "brandName": "example",
      "servingSize": 1,
      "servingSizeUnit": "example",
      "publishedDate": "example"
    }
  ],
  "food": {
    "fdcId": 1,
    "description": "example",
    "dataType": "example",
    "foodCategory": "example",
    "brandOwner": "example",
    "ingredients": "example",
    "servingSize": 1,
    "servingSizeUnit": "example",
    "publicationDate": "example",
    "nutrients": [
      {
        "number": "example",
        "name": "example",
        "amount": 1,
        "unitName": "example"
      }
    ]
  },
  "source": {
    "provider": "example",
    "url": "example"
  }
}

Discovery

/api/directory — full catalog of every endpoint
/openapi.json — OpenAPI 3.1 spec (per-op x-payment-info, x402Payment security)
/.well-known/x402 — machine-readable service descriptor for x402-aware crawlers
/.well-known/mcp/server-card.json — MCP SEP-1649 server card
/llms.txt — plain-text manifest for LLM ingestion

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.