@cyanheads/usda-mcp-server
Search foods, compare nutrients, and look up the full USDA FoodData Central database via MCP. STDIO or Streamable HTTP.
5 Tools โข 2 Resources
Overview
USDA FoodData Central โ the US government's authoritative food composition database, spanning roughly 400,000 foods across SR Legacy, Foundation, Survey (FNDDS), and Branded sources. Search foods by keyword or UPC, pull full nutrient profiles with portion scaling, and compare foods side by side from any MCP client. Runs as a stdio process, a local Streamable HTTP server, or the public hosted endpoint above.
| Tool | Description |
|---|
usda_search_foods | Search foods by keyword, ingredient, or UPC/GTIN across SR Legacy, Foundation, Survey (FNDDS), and Branded data sources |
usda_get_food | Full nutrient profile for one food by FDC ID, with optional per-portion scaling |
usda_get_foods | Batch nutrient fetch for 2โ20 FDC IDs in a single request |
usda_compare_foods | Side-by-side nutrient comparison for 2โ5 foods, formatted as a markdown table |
usda_list_nutrients | Static FDC nutrient reference table (~150 nutrients) with IDs, names, units, and categories |
Resources
| Resource | Description |
|---|
usda://food/{fdcId} | Full nutrient profile for a specific food by FDC ID |
usda://nutrients | Complete FDC nutrient reference list |
All resource data is also reachable via tools. Use usda_search_foods to discover FDC IDs before reading food resources.
Capability reference
- Query by keyword, ingredient name, or UPC/GTIN code; optional
dataType[] filter across SR Legacy, Foundation, Survey (FNDDS), and Branded, defaulting to ["SR Legacy"] (or ["Branded"] once brandOwner is set)
brandOwner and foodCategory filters narrow results; pageSize (max 50, default 10) and pageNumber paginate
- Returns FDC IDs plus a preview of key nutrients (energy, protein, fat, carbs) โ not a complete profile
- Typed errors:
query_empty (blank query), no_results (nothing matched in the requested data sources)
- Full nutrient profile for one
fdcId; optional nutrients[] filter to specific IDs
- Optional
quantity + unit (g / oz / lb / kg / serving) scales every value from the FDC per-100g basis; unit="serving" uses the food's first defined portion weight
- Returns
allPortions[] alongside the scaled result
- Typed errors:
not_found (bad FDC ID), quantity_without_unit, no_portion_data (serving requested but the food has no portion data)
- Batch fetch for 2โ20 FDC IDs in one call; values are per-100g only (no portion scaling)
nutrients[] filter strongly recommended โ full profiles for 20 foods are large
- Per-ID partial failure โ IDs that return no data land in
failed[] instead of aborting the batch
- Side-by-side comparison for 2โ5 FDC IDs, pivoted one row per nutrient and one column per food
- Defaults to 12 commonly compared nutrients (energy, protein, fat, saturated fat, carbs, fiber, total sugars, sodium, potassium, calcium, iron, vitamin C) unless
nutrients[] is given
- All values scaled to a common
quantity + unit basis (default 100g)
- Proceeds with the valid foods when some IDs return no data; only throws
too_few_foods when fewer than 2 resolve
- Rows where every food is null for that nutrient are filtered out
- Static reference table of ~150 tracked FDC nutrients โ no API call
- Optional
category filter: macronutrients, vitamins, minerals, lipids, amino_acids, other
- Returns each nutrient's ID, name, SR reference number, unit, and category โ resolve a name to the ID used by
nutrients[] elsewhere
usda://food/{fdcId} resource
- Same data as
usda_get_food without portion scaling โ full nutrient profile per 100g as application/json
fdcId must be a bare positive integer (no sign, leading zero, decimal, or exponent); anything else throws invalid_id
not_found when the ID doesn't exist in FDC
usda://nutrients resource
- Complete FDC nutrient reference โ same content as
usda_list_nutrients with no category filter
- Served as
application/json with a 1-hour public cache hint, since the table is bundled at build time and identical for every caller
Features
Built on @cyanheads/mcp-ts-core: stdio and Streamable HTTP transports, pluggable auth (none / jwt / oauth), swappable storage (in-memory, filesystem, Supabase, Cloudflare KV/R2/D1), structured logging with optional OpenTelemetry tracing.
FoodData Central-specific:
- Type-safe client for the USDA FoodData Central REST API (
api.nal.usda.gov/fdc/v1)
- Normalization layer that handles inconsistent API response shapes across search, single-food, and batch endpoints
- Batch API endpoint (
/foods) with per-food partial failure reporting
- HTML response detection (rate-limit proxy returns 200 HTML) with service-unavailable error surfacing
- Static nutrient reference dictionary โ ~150 nutrients with FDC IDs, SR numbers, units, and categories; no API call required
Agent-friendly output:
- Provenance preserved โ FDC data source (
dataType) on every food result so callers know whether they're reading curated research data or label-derived branded values
- Partial failure reporting โ batch tools (
usda_get_foods, usda_compare_foods) return successes alongside structured failed[] / missingData[] entries rather than failing the whole request
- Cross-reference hints โ FDC IDs and tool names in descriptions so agents know exactly which call to make next (search โ get โ compare workflow)
Getting started
Public Hosted Instance
A public instance is available at https://usda.caseyjhand.com/mcp โ no installation required. Point any MCP client at it via Streamable HTTP:
{
"mcpServers": {
"usda-mcp-server": {
"type": "streamable-http",
"url": "https://usda.caseyjhand.com/mcp"
}
}
}
Self-Hosted / Local
Add the following to your MCP client configuration file. See data.gov API key signup to generate a free API key.
{
"mcpServers": {
"usda-mcp-server": {
"type": "stdio",
"command": "bunx",
"args": ["@cyanheads/usda-mcp-server@latest"],
"env": {
"MCP_TRANSPORT_TYPE": "stdio",
"MCP_LOG_LEVEL": "info",
"USDA_FDC_API_KEY": "your-api-key"
}
}
}
}
Or with npx (no Bun required):
{
"mcpServers": {
"usda-mcp-server": {
"type": "stdio",
"command": "npx",
"args": ["-y", "@cyanheads/usda-mcp-server@latest"],
"env": {
"MCP_TRANSPORT_TYPE": "stdio",
"MCP_LOG_LEVEL": "info",
"USDA_FDC_API_KEY": "your-api-key"
}
}
}
}
Or with Docker:
{
"mcpServers": {
"usda-mcp-server": {
"type": "stdio",
"command": "docker",
"args": [
"run", "-i", "--rm",
"-e", "MCP_TRANSPORT_TYPE=stdio",
"-e", "USDA_FDC_API_KEY=your-api-key",
"ghcr.io/cyanheads/usda-mcp-server:latest"
]
}
}
}
For Streamable HTTP, set the transport and start the server:
MCP_TRANSPORT_TYPE=http MCP_HTTP_PORT=3010 USDA_FDC_API_KEY=your-api-key bun run start:http
Prerequisites
- Bun v1.4.0 or higher (or Node.js v24+).
- A free USDA FDC API key โ register at api.data.gov/signup. Required for food search, lookup, and comparison calls;
usda_list_nutrients and the static nutrient reference work without it.
Installation
- Clone the repository:
git clone https://github.com/cyanheads/usda-mcp-server.git
- Navigate into the directory:
- Install dependencies:
- Configure environment:
Configuration
| Variable | Description | Default |
|---|
USDA_FDC_API_KEY | Required for FoodData Central-backed tools (search, get, batch, compare) โ not for startup or usda_list_nutrients. Get a free key at api.data.gov. | โ |
MCP_TRANSPORT_TYPE | Transport: stdio or http. | stdio |
MCP_HTTP_PORT | Port for HTTP server. | 3010 |
MCP_AUTH_MODE | Auth mode: none, jwt, or oauth. | none |
MCP_LOG_LEVEL | Log level (RFC 5424). | info |
LOGS_DIR | Directory for log files (Node.js only). | <project-root>/logs |
STORAGE_PROVIDER_TYPE | Storage backend. | in-memory |
OTEL_ENABLED | Enable OpenTelemetry instrumentation (spans, metrics, completion logs). | false |
See .env.example for the full list of optional overrides.
Running the server
Local development
-
Build and run:
bun run rebuild
bun run start:stdio
bun run start:http
-
Run checks and tests:
bun run devcheck
bun run test
bun run lint:mcp
Docker
docker build -t usda-mcp-server .
docker run --rm -e USDA_FDC_API_KEY=your-key -p 3010:3010 usda-mcp-server
The Dockerfile defaults to HTTP transport, stateless session mode, and logs to /var/log/usda-mcp-server. OpenTelemetry peer dependencies are installed by default โ build with --build-arg OTEL_ENABLED=false to omit them.
Project structure
| Directory | Purpose |
|---|
src/index.ts | createApp() entry point โ registers tools, resources, and inits FdcService. |
src/config | Server-specific environment variable parsing and validation with Zod (USDA_FDC_API_KEY). |
src/mcp-server/tools | Tool definitions (*.tool.ts) โ search, get, batch, compare, list-nutrients. |
src/mcp-server/resources | Resource definitions (*.resource.ts) โ food profile and nutrient reference. |
src/services/fdc | FdcService โ USDA FDC API client, normalization, and static nutrient reference data. |
tests/ | Unit tests mirroring src/ โ 50 tests across all tools and resources. |
Development guide
See CLAUDE.md for development guidelines and architectural rules. The short version:
- Handlers throw, framework catches โ no
try/catch in tool logic
- Use
ctx.log for request-scoped logging, ctx.state for tenant-scoped storage
- Register new tools and resources via the barrels in
src/mcp-server/*/definitions/index.ts
- Wrap external API calls: validate raw โ normalize to domain type โ return output schema; never fabricate missing fields
Contributing
Issues are welcome. Run checks and tests before submitting:
bun run devcheck
bun run test
License
Apache-2.0 โ see LICENSE for details.