CMS Blue Button 2.0
Blue Button 2.0 is the Centers for Medicare & Medicaid Services (CMS) API that lets Medicare beneficiaries share their Parts A, B, and D claims data with applications they trust. It is a FHIR R4 API conforming to the CARIN Blue Button Implementation Guide (CARIN Consumer Directed Payer Data Exchange), serving ExplanationOfBenefit, Patient, and Coverage resources for 60+ million people with Medicare. Access is patient-facing - each beneficiary authorizes an app through an OAuth 2.0 authorization-code flow (with mandatory PKCE) on Medicare.gov, choosing whether to share demographic data. A self-serve sandbox with synthetic enrollee data is open to everyone; production credentials are free but require CMS approval of the application.
CMS Blue Button 2.0 publishes 5 APIs on the APIs.io network, including Coverage API, ExplanationOfBenefit API, Metadata API, and 2 more. Tagged areas include Blue Button, CARIN, Medicare, FHIR, and Claims Data.
CMS Blue Button 2.0’s developer surface includes authentication, documentation, sandbox, getting-started guide, and 8 more developer resources.
Kin Score
APIs 5
Individual APIs this provider publishes, each with its own machine-readable definition.
CMS Blue Button 2.0 Coverage API
Medicare coverage resources, one per coverage type.
CMS Blue Button 2.0 ExplanationOfBenefit API
Medicare Parts A, B, and D claims as CARIN Blue Button EOB profiles.
CMS Blue Button 2.0 Metadata API
FHIR capability statement.
CMS Blue Button 2.0 Patient API
Beneficiary demographic and administrative data.
CMS Blue Button 2.0 UserInfo API
OpenID Connect userinfo for the authorizing beneficiary.
Open Collections 7
Open, tool-agnostic API collections (OpenAPI-derived and Bruno).
API Collection
OPEN COLLECTIONCMS Blue Button 2.0 Coverage API
OPEN COLLECTIONCMS Blue Button 2.0 Coverage ExplanationOfBenefit API
OPEN COLLECTIONCMS Blue Button 2.0 Coverage Metadata API
OPEN COLLECTIONCMS Blue Button 2.0 Coverage Patient API
OPEN COLLECTIONCMS Blue Button 2.0 Coverage UserInfo API
OPEN COLLECTIONCMS Blue Button 2.0 API
OPEN COLLECTIONScroll for all 7
Pricing Plans 1
Published pricing tiers and plan structures.
Rate Limits 1
Documented rate limits and quota policies.
Cms Blue Button Rate Limits
RATE LIMITSFinOps 1
Cost, billing, and metering signals for API financial operations.
Cms Blue Button Finops
FINOPSSecurity Posture 2
Authentication, domain security, vulnerability disclosure, and trust-center signals.
Agentic Access 1
Recommended x-agentic-access execution contracts for AI agents.
Resources
Get Started 2
Portal, sign-up, and the first successful call
Documentation 1
Reference material describing how the API behaves
Agent Surfaces 1
MCP servers, agent skills, and machine-readable catalogs
Build 1
SDKs, sample code, and the tooling you integrate with
Access & Security 2
Authentication, authorization, and security posture
Operate 1
Status, limits, changes, and where to get help
Commercial 3
Pricing, plans, and the legal terms of use
Company 1
The organization behind the API
Source (apis.yml)
Work with this as data
Every provider here is available over the APIs.io API and to AI agents over MCP.
MCP server
One button, every client — Claude, Cursor, VS Code and the rest.
https://apis.io/mcp
Tools for providers
9 MCP tools reach this
find_providersBrowse and filter every provider in the catalog.get_provider_artifactsEvery artifact this provider publishes, grouped by type.get_provider_operationsEvery operation across all of their OpenAPIs — one call instead of parsing every spec.get_provider_toolsEvery MCP tool they ship, with the operation each wraps.get_provider_evidenceHow each part of their score was established. Free — the basis for a claim should not sit behind it.get_provider_ratingPRO — composite, band, trend and facet scores.apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.resolveTurn a domain, URL or GitHub org into the provider it belongs to.find_cohortsEvery scored population of providers in the catalog.
Call it yourself
curl for this page
curl "https://apis.io/api/v1/providers/cms-blue-button"
curl "https://apis.io/api/v1/providers?limit=25"
curl "https://apis.io/api/v1/providers/cms-blue-button/operations?limit=25"
curl "https://apis.io/api/v1/providers/cms-blue-button/evidence"
Discovery needs no key. Ratings and market analysis are Pro.