{
  "name": "aca-marketplace-enrollment-mcp",
  "title": "HealthMesh · ACA Marketplace Enrollment MCP",
  "version": "0.1.0",
  "description": "ACA Health Insurance Marketplace enrollment: Open Enrollment plan selections by state (50 states + DC + US), county and ZIP (HealthCare.gov states) for plan years 2020–2026 — new vs returning consumers, APTC/CSR, premiums, metal level, age, income, race/ethnicity, rural — plus monthly and annual effectuated (paid) enrollment 2016 onward, from CMS public use files, with CMS footnotes, data-quality flags and comparability-aware year-over-year changes.",
  "healthmesh_domain": "Eligibility & Enrollment",
  "datasets": [
    "ELIG-04"
  ],
  "mcp_endpoint": "https://aca-marketplace-enrollment.healthmesh.ai/mcp",
  "transport": "Streamable HTTP (stateless, JSON responses)",
  "authorization": "none",
  "auth_mode": "off",
  "docs": "https://github.com/HendrikK/healthmesh/tree/main/servers/aca-marketplace-enrollment-mcp#readme",
  "contact": "hendrik.kleine@gmail.com",
  "data_source": {
    "name": "CMS Marketplace Open Enrollment Period Public Use Files + data.cms.gov Effectuated Enrollment",
    "url": "https://www.cms.gov/data-research/statistics-trends-and-reports/marketplace-products",
    "license": "U.S. Government Work (public domain) – https://www.usa.gov/government-works",
    "refresh": "daily check; OEP PUFs yearly (spring), effectuated enrollment periodic"
  },
  "tools": [
    {
      "name": "aca_oep_get_plan_selections",
      "title": "ACA Marketplace OEP plan selections (state / county / ZIP)",
      "description": "Returns ACA Health Insurance Marketplace Open Enrollment Period (OEP) plan-selection statistics from the CMS OEP Public Use Files for a plan year: total plan selections, new vs returning consumers, APTC and CSR recipients, average premium before/after APTC, and optional breakdowns (metal level, age, sex, race/ethnicity, household income as % FPL, rural, applications, weekly cumulative selections, agent/broker, dental, BHP). geo_level=state covers all 50 states + DC ('US' = CMS national total; platform HealthCare.gov or SBE); geo_level=county and geo_level=zip cover HealthCare.gov states only (CMS publishes no county/ZIP files for State-based Exchanges) and the ZIP file has only plan_selections, aptc_consumers and avg_aptc. These are plan selections at the end of OEP, NOT effectuated (paid) enrollment — use aca_get_effectuated_enrollment for that. Null values carry a reason in `unavailable` (suppressed '*', not_reported 'NR', not_applicable '+', not_published). OEP plan years 2020–2026 are loaded (state, county and ZIP PUFs); 2014–2019 are not (CMS published them as XLSX workbooks only)."
    },
    {
      "name": "aca_oep_get_trend",
      "title": "ACA Marketplace OEP metric trend across plan years",
      "description": "Returns a plan-year series (2020–2026) of one OEP metric for a state, the national total ('US'), or a county, with year-over-year changes. COMPARABILITY: a change is set to null (comparable=false) when CMS says the years are not directly comparable — the state moved between HealthCare.gov and its own State-based Exchange (e.g. GA 2025, IL 2026), or a CMS PUF FAQ note reports a program change or revised definitions for that metric group (e.g. NY financial-assistance metrics). Pass allow_noncomparable=true to compute them anyway (still marked). County series only exist for years the state used HealthCare.gov. Metrics: any count, average premium/APTC, or derived % (e.g. pct_aptc, pct_new_consumers, pct_silver). Weekly cumulative counts are excluded (week windows differ by year)."
    },
    {
      "name": "aca_oep_compare_states",
      "title": "Rank / compare states on an ACA Marketplace OEP metric",
      "description": "Ranks states on one OEP metric for a plan year, optionally only HealthCare.gov or only State-based Exchange (SBE) states, or by change versus an earlier plan year (rank_by=change_pct|change_abs). Each row has the state's platform, footnotes (CMS state notes for this metric) and data_quality_flags; states without a value are listed in not_reported with the reason (e.g. 'NR' = SBE did not report). CAVEAT: CMS says HealthCare.gov states are directly comparable but SBE figures are self-reported and definitions may vary; summary counts SBE and flagged rows both among the returned rows (*_returned) and across all ranked states (*_total). Changes across a platform switch or a CMS comparability note are null unless allow_noncomparable=true. Raw counts are not population-adjusted."
    },
    {
      "name": "aca_oep_compare_counties",
      "title": "Rank counties on an ACA Marketplace OEP metric (HealthCare.gov states)",
      "description": "Ranks the counties of one state (or all HealthCare.gov counties when state is omitted) on an OEP metric for a plan year, or by change versus an earlier plan year (rank_by=change_pct|change_abs). County PUFs exist only for states using HealthCare.gov in that year; for a State-based Exchange state (e.g. GA from 2025, IL from 2026, CA always) the tool returns a NOT_FOUND error naming the years with county data. Values 1–10 are suppressed by CMS ('*'); suppressed counties are counted in summary.counties_suppressed and not ranked. Use min_plan_selections to drop tiny counties from percentage rankings."
    },
    {
      "name": "aca_get_effectuated_enrollment",
      "title": "ACA Marketplace effectuated (paid) enrollment",
      "description": "Returns effectuated Marketplace enrollment — people with an active, paid policy — from CMS (data.cms.gov Health Insurance Exchanges effectuated enrollment datasets). granularity=annual: average monthly effectuated enrollment per plan year with APTC/CSR counts and shares, average premium, average APTC and average premium after APTC (2016 onward). granularity=monthly: effectuated enrollment for each month (2016 onward; the newest months may be revised). With compare_to_oep=true (default), each year is paired with the OEP plan selections for that year and the ratio is shown — effectuated enrollment is normally lower than plan selections because some consumers never pay their first premium or leave during the year."
    },
    {
      "name": "aca_describe_dataset",
      "title": "Describe the ACA Marketplace enrollment data on this server",
      "description": "Describes coverage and semantics: loaded plan years per level (state/county/ZIP), each state's platform (HealthCare.gov vs State-based Exchange) per year, every metric with label, group, unit, levels and the years CMS published it, derived metrics, marker meanings (*, NR, +, not_published), data-quality flag rules, CMS year-over-year comparability notes, effectuated-enrollment coverage, source URLs with fetch dates and checksums, known gaps, and refresh status. Call first when unsure which metric, level or year to use."
    }
  ]
}