cms.gov
The Centers for Medicare & Medicaid Services (CMS) is a U.S. federal agency that administers Medicare, Medicaid, CHIP, and Health Insurance Marketplace programs. Its public web properties include developer tools and datasets for health insurance, claims, and program data access.
cms.gov publishes three developer-facing HTTP APIs: the public CMS Data API, the key-authenticated Marketplace API, and the OAuth 2.0-protected Blue Button FHIR API.
- Marketplace APIdiscovered
- CMS Data APIdiscovered
- Blue Button APIdiscovered
Request a key using the Marketplace API Key Request form. CMS states keys can be issued to anyone who requests access and are emailed automatically when renewed every 60 days.
For sandbox, create an application in the Blue Button Sandbox and save its client_id and client_secret. For production, complete the production access process and CMS will provide production credentials after approval. Blue Button uses OAuth 2.0 Authorization Code with required PKCE.
conventions · 0/8 published
- integrations.json✗
/.well-known/integrations.json - llms.txt✗
/llms.txt - API catalog✗
/.well-known/api-catalog - OpenAPI document✗
/api/schema/, /openapi.json, /swagger.json, /api/openapi.json, or /v1/openapi.json - MCP server card✗
/.well-known/mcp/server-card.json - OAuth protected resource✗
/.well-known/oauth-protected-resource - Agent card✗
/.well-known/agent-card.json - Agent skills✗
/.well-known/agent-skills/index.json
Publish these signals → /publishing