Open Primitive API

Domains

Endpoints

Domain	Endpoint	Source	Parameters	Freshness
alerts	`/v1/alerts`	Cross-domain	none	real-time
ask	`/v1/ask`	All domains	`q`	real-time
cars	`/v1/cars`	NHTSA	`year`, `make`, `model`	continuous
compare	`/v1/compare`	Multi-domain	`type`, `a`, `b`	real-time
demographics	`/v1/demographics`	Census Bureau	`zip`	annual
drugs	`/v1/drugs`	FDA FAERS	`name`	quarterly
flights	`/v1/flights`	FAA NAS	none; `/v1/flights/:iata`	real-time
food	`/v1/food`	FDA	`q` (optional)	daily
health	`/v1/health`	PubMed	`q`	continuous
hospitals	`/v1/hospitals`	CMS	`q` or `id`	quarterly
jobs	`/v1/jobs`	BLS	`series` (optional)	monthly
location	`/v1/location`	Census + EPA + CMS	`zip`	composite
nutrition	`/v1/nutrition`	USDA FoodData	`q` or `id`	continuous
products	`/v1/products`	CPSC	`q` (optional)	daily
safety	`/v1/safety`	Cross-domain	`zip`	composite
sec	`/v1/sec`	SEC EDGAR	`q` or `cik`	daily
water	`/v1/water`	EPA SDWIS	`zip`; `/v1/water/:pwsid`	quarterly
weather	`/v1/weather`	NWS / Open-Meteo	`zip` or `state`	real-time
air	`/v1/air`	EPA AQS	`zip` or `state`	real-time
clinical-trials	`/v1/clinical-trials`	ClinicalTrials.gov	`q`	daily
context	`/v1/context`	Archive	`entity`	real-time
courts	`/v1/courts`	CourtListener	`q`	daily
drug-interactions	`/v1/drug-interactions`	FDA Drug Labels	`drug1`, `drug2`	continuous
drug-labels	`/v1/drug-labels`	NLM DailyMed	`name`	continuous
earthquakes	`/v1/earthquakes`	USGS	none	real-time
education	`/v1/education`	Dept of Education	`q` or `id`	annual
eligible	`/v1/eligible`	HHS / CMS / IRS / HUD	`income`, `household`, `state`	annual
federal-register	`/v1/federal-register`	Federal Register	`q`	daily
infrastructure	`/v1/infrastructure/electricity`	EIA	`state`	monthly
meat	`/v1/meat`	USDA FSIS	`q` (optional)	daily
reclaim	`/v1/reclaim/search`	State + Federal	`first_name`, `last_name`	monthly
risk	`/v1/risk`	Cross-domain	`zip`	composite
spending	`/v1/spending`	USAspending.gov	`q`	daily
changes	`/v1/changes`	Archive	`date`	daily

Format

Response Envelope

Every response returns this structure.

Field	Type	Description
`domain`	string	Dataset identifier
`source`	string	Federal agency
`source_url`	string	Upstream URL
`freshness`	string	ISO 8601 timestamp of last data pull
`confidence`	number	0 to 1 score of data completeness
`citations`	array	Source references for direct use
`proof`	string	Ed25519 signature for verification
`data`	object	Domain-specific payload

// GET /v1/cars?year=2024&make=honda&model=civic { "domain": "cars", "source": "NHTSA", "source_url": "https://api.nhtsa.gov/recalls/recallsByVehicle?make=honda&model=civic&modelYear=2024", "freshness": "2026-03-21T08:14:22Z", "confidence": 0.94, "citations": ["NHTSA Office of Defects Investigation"], "proof": "ed25519:a1b2c3...", "data": { "recalls": [...] } }

Trust

Data Quality

Confidence scores reflect upstream reporting methodology, not API reliability.

Domain	Methodology	Confidence	Known Gaps
alerts	composite, real-time	0.70	Dependent on source domain quality
cars	mandatory manufacturer reporting	0.94	Pre-2000 vehicles have sparse data
compare	derived from source domains	varies	Quality matches the weaker input
demographics	American Community Survey, sampled	0.85	5-year estimates; rural under-sampled
drugs	voluntary reporting (MedWatch)	0.10	Captures 1-10% of actual adverse events
flights	FAA real-time + BTS historical	0.80	BTS data 12-18 months delayed
food	mandatory enforcement actions	0.85	Voluntary recalls may not appear immediately
health	peer-reviewed literature search	0.60	Indexed abstracts only; no full-text
hospitals	CMS mandatory reporting	0.90	VA and military hospitals excluded
jobs	BLS survey-based estimates	0.88	Subject to revision; gig work under-counted
location	composite of Census, EPA, CMS	0.75	ZIP boundary mismatches in cross-domain joins
nutrition	lab-analyzed and industry-submitted	0.92	Branded products self-reported
products	mandatory and voluntary recalls	0.80	Voluntary recalls may lag weeks
safety	composite score across domains	0.65	Only as strong as weakest domain
sec	mandatory public filings	0.95	Private companies not covered
water	mandatory but delayed (SDWIS)	0.70	Small systems under-report; data lags 6 months
weather	NWS observational + modeled	0.90	Forecast accuracy degrades beyond 72 hours
air	EPA AQS monitoring stations	0.80	Rural areas have sparse monitors
clinical-trials	ClinicalTrials.gov registry	0.92	Registration compliance varies
context	internal archive / change detection	0.75	Only covers previously queried entities
courts	CourtListener RECAP archive	0.70	State courts under-represented
drug-interactions	FDA label cross-reference	0.75	Only covers FDA-labeled interactions
drug-labels	NLM DailyMed mandatory labeling	0.93	OTC labels may lag
earthquakes	USGS seismic network	0.95	Magnitude <2.5 not included
education	Dept of Ed College Scorecard	0.85	Small institutions may lack data
eligible	statutory thresholds (HHS, IRS, HUD)	0.80	State-level variation not fully modeled
federal-register	Federal Register API	0.95	Pre-1994 documents not digitized
infrastructure	EIA survey data	0.85	State-level only; no local granularity
meat	USDA FSIS mandatory inspection	0.90	Game and exotic meats under-covered
reclaim	state unclaimed property databases	0.65	Coverage varies by state; name matching imperfect
risk	composite cross-domain scoring	0.70	Only as strong as weakest input domain
spending	USAspending.gov mandatory reporting	0.90	Sub-awards may lag primary awards
changes	internal daily diff archive	0.80	Only detects changes in monitored domains

Auth

Authentication

No API key required. Completely free, no limits. Just call the endpoints.

# Just call it curl https://api.openprimitive.com/v1/cars?year=2024&make=toyota&model=camry

Connect

Integration

Protocol	Location
MCP	`npx @openprimitive/mcp-server`
A2A	`/.well-known/agent.json`
OpenAPI	`/openapi.json`
llms.txt	`/llms.txt`
OPP manifest	`/.well-known/opp.json`

# Add to Claude Desktop config (claude_desktop_config.json) { "mcpServers": { "open-primitive": { "command": "npx", "args": ["@openprimitive/mcp-server"] } } }

Internal

Utility Endpoints