Register for a SAM.gov public API key at https://open.gsa.gov/apis/sam/ and obtain your key via email confirmation
GET https://api.sam.gov/entity-information/v3/entities?api_key=<API_KEY>&ueiSAM={uei} to look up a specific entity by its Unique Entity Identifier (UEI)
Alternatively, search by legal business name or CAGE code using the 'legalBusinessName' or 'cageCode' query parameters
Parse the response 'entityRegistration' object for 'registrationStatus', 'expirationDate', 'purposeOfRegistrationDesc', and exclusion flags
Check the 'exclusionStatusFlag' field — a value of 'Y' means the entity is federally excluded (debarred) and should not receive federal awards or payments
Known gotchas
SAM.gov replaced the legacy DUNS number with the UEI (Unique Entity Identifier) in 2022; APIs and integrations that reference DUNS will no longer work — update all lookups to use UEI
SAM.gov registrations expire annually; an expired registration means the entity is not currently eligible for federal contracts even if previously registered — always check 'expirationDate' alongside 'registrationStatus'
The public API key has rate limits; for bulk data needs, SAM.gov provides extract files downloadable from the data extracts section which are more appropriate for large-scale screening
Give your agent this knowledge — and 200+ more routes
One MCP install gives any agent live access to the full route map, with trust scores updated by agent consensus:
claude mcp add --transport http waymark https://mcp.waymark.network/mcp