> ## Documentation Index
> Fetch the complete documentation index at: https://docs.haau3.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Find organizations, payers and networks

> Search `Organization` by name, NPI, parent (`partof`) or type. `type=ntwk` lists the insurance networks the directory holds and `type=pay` its payers; any other type, `active` and the address parameters narrow a search but cannot stand alone.

The directory records networks by the text of their type rather than a code. This service searches that text for `type=ntwk` and confirms every answer is a network; if the directory changes how it records them, the search answers 502 rather than serve something else.

An NPI search can return a parent organization beside the practice, when the parent lists the NPI among several. `_revinclude` brings the roles, affiliations, locations and endpoints that point at each match, up to 100 per page.



## OpenAPI

````yaml /api-reference/openapi.json get /v1/fhir/r4/Organization
openapi: 3.1.0
info:
  title: haau3 Platform API
  version: 1.0.0-preview.4
  description: >-
    The haau3 platform API is in preview: it may change as we build, usually to
    add features or improve performance. Endpoints require an API key, sent as
    `Authorization: Bearer <key>`. Requests without a valid key return 401.
    Create a key in the dashboard at https://platform.haau3.com; a new
    organization starts on the free Developer plan. From 2026-11-01 a request
    past one of its plan's limits (requests a minute on every plan, requests a
    month on Developer) returns 429 with `Retry-After`. Every error under
    `/v1/fhir` is a FHIR `OperationOutcome` and every other error an RFC 9457
    problem; https://docs.haau3.com/errors lists every status, whether to retry
    it, and what a method a path does not take answers.
servers:
  - url: https://api.haau3.com
    description: Production
security:
  - bearerAuth: []
tags:
  - name: Scheduling
    description: 'Provider availability (SMART Scheduling Links): slots and publishers.'
  - name: FHIR base
    description: >-
      What the FHIR R4 base at `/v1/fhir/r4` answers for every service on it:
      the `CapabilityStatement` that lists them all, and batch Bundles that
      carry several requests to any of them in one round trip.
  - name: Terminology
    description: >-
      FHIR terminology operations over the code systems listed in
      TerminologyCapabilities. Some are resolved from their own source when you
      ask; others are held here at a named release, which that resource also
      names.
  - name: Provider directory
    description: >-
      CMS's National Provider Directory as FHIR R4: practitioners and their
      roles, organizations, payers and insurance networks, network membership,
      healthcare services, locations and endpoints. Every parameter the service
      serves is declared here, and any other is refused by name rather than
      ignored.
  - name: Questionnaires
    description: >-
      FHIR Questionnaire, served as its source publishes it. This service holds
      copies of a curated set and reaches any other questionnaire its source
      publishes by canonical URL, as well as forms published at their own
      address under places this service is set up to reach. Read one by id, and
      build the QuestionnaireResponse in your own application.
  - name: Plan Benefits
    description: >-
      FHIR InsurancePlan: what a Medicare Advantage or ACA Marketplace plan
      covers and what a member pays, read from the files CMS publishes. Every
      plan names the CMS release it was read from. Read a plan by its id, or
      search by identifier, name, state or county, and check whether the CMS
      National Provider Directory lists providers in a plan's network.
  - name: MedList
    description: >-
      One reconciled medication list from one patient's FHIR medication records,
      as US Core MedicationRequests with a Provenance for each. This operation
      receives patient data, so send it only under an executed agreement.
paths:
  /v1/fhir/r4/Organization:
    get:
      tags:
        - Provider directory
      summary: Find organizations, payers and networks
      description: >-
        Search `Organization` by name, NPI, parent (`partof`) or type.
        `type=ntwk` lists the insurance networks the directory holds and
        `type=pay` its payers; any other type, `active` and the address
        parameters narrow a search but cannot stand alone.


        The directory records networks by the text of their type rather than a
        code. This service searches that text for `type=ntwk` and confirms every
        answer is a network; if the directory changes how it records them, the
        search answers 502 rather than serve something else.


        An NPI search can return a parent organization beside the practice, when
        the parent lists the NPI among several. `_revinclude` brings the roles,
        affiliations, locations and endpoints that point at each match, up to
        100 per page.
      operationId: searchOrganization
      parameters:
        - name: name
          in: query
          required: false
          schema:
            type: string
            minLength: 1
            maxLength: 100
          description: Matches the organization's name.
        - name: identifier
          in: query
          required: false
          schema:
            type: string
            minLength: 1
            maxLength: 256
          description: >-
            An organization's NPI, as `{system}|{npi}` or a bare 10-digit value,
            under the same systems `Practitioner` accepts. An NPI search can
            return more than the practice that holds the NPI: a parent
            organization that lists it among several NPIs is a match too,
            because it carries the NPI as an NPI.
        - name: partof
          in: query
          required: false
          schema:
            type: string
            minLength: 1
            maxLength: 256
          description: >-
            The organizations that are part of one organization. Give a
            Organization id, `Organization/{id}`, or the `fullUrl` this service
            returned. An address on another server is refused.
        - name: type
          in: query
          required: false
          schema:
            type: string
            minLength: 1
            maxLength: 256
          description: >-
            An organization type from
            `http://terminology.hl7.org/CodeSystem/organization-type`, bare or
            with that system: `prov` for healthcare providers, `pay` for payers,
            `ntwk` for insurance networks. `ntwk` is also accepted under
            Plan-Net's
            `http://hl7.org/fhir/us/davinci-pdex-plan-net/CodeSystem/OrgTypeCS`.
            `type=ntwk` and `type=pay` may stand alone, to list every network or
            every payer; any other type narrows a search. The directory records
            networks by the text of their type rather than a code; this service
            searches that text and confirms each answer is a network, and
            answers 502 rather than serve one that is not.
          example: ntwk
        - name: active
          in: query
          required: false
          schema:
            type: string
            enum:
              - 'true'
              - 'false'
          description: '`true` or `false`. Narrows a search; cannot be used on its own.'
        - name: address-city
          in: query
          required: false
          schema:
            type: string
            minLength: 1
            maxLength: 100
          description: >-
            Narrows a search by city; cannot be used on its own. Matches any of
            the organization's addresses, so a result can still list addresses
            in another city.
        - name: address-state
          in: query
          required: false
          schema:
            type: string
            minLength: 1
            maxLength: 50
          description: >-
            Narrows a search by state; cannot be used on its own. Matches any of
            the organization's addresses, so a result can still list addresses
            in another state.
        - name: address-postalcode
          in: query
          required: false
          schema:
            type: string
            minLength: 1
            maxLength: 100
          description: >-
            Narrows a search by postal code; cannot be used on its own. Matches
            any of the organization's addresses, so a result can still list
            addresses in another postal code.
        - name: _include
          in: query
          required: false
          schema:
            minItems: 1
            maxItems: 16
            type: array
            items:
              type: string
              enum:
                - Organization:partof
          style: form
          explode: true
          description: >-
            `Organization:partof` brings the organization each match is part of.
            Repeat the parameter to include several. Included entries do not
            count toward `_count`.
        - name: _revinclude
          in: query
          required: false
          schema:
            minItems: 1
            maxItems: 16
            type: array
            items:
              type: string
              enum:
                - PractitionerRole:organization
                - OrganizationAffiliation:primary-organization
                - OrganizationAffiliation:participating-organization
                - Location:organization
                - Endpoint:organization
                - Organization:partof
          style: form
          explode: true
          description: >-
            Bring the records that point at each match:
            `PractitionerRole:organization`,
            `OrganizationAffiliation:primary-organization`,
            `OrganizationAffiliation:participating-organization`,
            `Location:organization`, `Endpoint:organization` or
            `Organization:partof`. Repeat the parameter to include several.
            Included entries do not count toward `_count`. The directory returns
            at most 100 included records per page; a page with more is refused
            with a 502 rather than served short.
        - name: _id
          in: query
          required: false
          schema:
            type: string
            pattern: ^[A-Za-z0-9\-.]{1,64}$
          description: >-
            A Organization id. Searching by id rather than reading it lets one
            request also bring the records an `_include` or `_revinclude` names.
        - name: _summary
          in: query
          required: false
          schema:
            type: string
            enum:
              - count
          description: >-
            `count` only: answers how many records match, as `total`, with no
            entries. Cannot be combined with `_include`, `_revinclude`, `_count`
            or `page`.
        - name: _count
          in: query
          required: false
          schema:
            type: integer
            minimum: 1
            maximum: 100
          description: >-
            Results are paged. `_count` sets the page size (1 to 100); a larger
            value is refused rather than quietly reduced. Follow `link` with
            relation `next` to continue. The cursor it carries is opaque and
            must not be constructed or modified.
          example: 2
        - name: page
          in: query
          required: false
          schema:
            type: string
            minLength: 1
            maxLength: 8192
          description: >-
            Continuation cursor. Opaque: follow the `next` link from a previous
            response, and never construct or modify it. Cursors expire.
        - $ref: '#/components/parameters/XRequestId'
      responses:
        '200':
          description: >-
            A FHIR `Bundle` with `type: searchset`. `total` is present when the
            directory sends one.
          content:
            application/fhir+json:
              schema:
                $ref: '#/components/schemas/Bundle'
              examples:
                Insurance networks:
                  summary: Insurance networks
                  value:
                    resourceType: Bundle
                    type: searchset
                    link:
                      - relation: self
                        url: >-
                          https://api.haau3.com/v1/fhir/r4/Organization?type=ntwk&_count=2
                      - relation: next
                        url: >-
                          https://api.haau3.com/v1/fhir/r4/Organization?type=ntwk&_count=2&page=AAMA-EFRSURBSGd2bzlHTkh2NkZNeXNGMkNKelNQaUp6aCtWTXNCNXh6R0owVG0xQ1RtRzZRRlFsZHdrMHBleFdXNHJWUWdqdVFnUkFBQUFmakI4QmdrcWhraUc5dzBCQndhZ2J6QnRBZ0VBTUdnR0NTcUdTSWIzRFFFSEFUQWVCZ2xnaGtnQlpRTUVBUzR3RVFRTUcwNjZ1RHRDSHg2cmFmSjhBZ0VRZ0R2TlNZOHNEOC9Bdk1xQTR4ZG1PT3gzWGo5eTI2KzFFVm1ndnE0ZThIMllBVXU0bUlBL2NkaDd6NFg4dGNLWFFhWHBaTFBnNGdNZUp3Y1lHZz0983p39CwCUjpWSugnFrlXI6R_qkjtsw1vB86p5RVBZjMXTQbnDC-9W1MfBa0AXsABVevK4CtJA4sduYGsCDLx6RquJ7XNsC9I1aLOys1oap16pqiMZpy5SQQs_00NkQMjBC5aon49YGXY9w1ScGWcPNEYjj1JX6FTBlC0OQH21mLj5wDj_m3LL3e4Hp80rIx1D2IZfOJZhxS2eCXMxW8F4CUx-RXEdRkK9BxPhoDHiTTc8TzRRXghyeO7E5uamGV3gekBMm1IUxPJlS6Sn_Gzcy2W_gwcz3TdxMXwgcCrQ_JyeCHwTbuAgQz4vTCIXDaSVjVuNH_KbLdHet6OQ9UcFqtTJyZlldVz5Y-Q0yZvPZi4pKa6WUymNEmcH0hLYcPsAjBYlkKWkv3nr5_5nyP12QuIt0KKA5fOoX8UGf4SUtdIYFFPrNMOuAWLTGGrXRIvS_QSGiLAsVJjmq3QXd2Rjt_OOjuLJTiQGvRMljPahGyZuS2HrzDU7PIsENSF2w3ViieOKVEtbQPW3jtth4QdtJmx7s0m7gsv6xokEzfffObWlDirjnmmUVnvlxsC9YkHER-VpsRDF_Uk2jh9ufasN-INBU8jj2trOfMPsce2TVMlgp9Ei8W5ydEaZsj3959ErJ_k_bwbeOOJipZCNwBeyBRmCY5E0ZGGY-LeKP0z0dkTE1eLSZqMFKPEFcs_xhXe12JXJeAGzjxZ7D-jLZtKcUjLviLdblNE7VxfkcgeAquZPPzjVG83_KNkMswh4fZ479bRKLnRZvdT5yjJed-gDbfxXL5IOMM4BbranhQJf_9SzkZYZu8le-1i3kI_4FtP8VJYOdPopvDmXZLV8TJMbq_dp_imQh_6pk8XbTPegFYqrU1l3x4n3YZpOABK2VI9Qgj9-BYH3oUfqX6njGKyV9blC1VAsDIDac7BtwlN0dcWPactGT3NUae-lPiPgok8QmUwMyZPB0X_6pDGy3hrlWhhxBvq0Olz7lxJ9scXUN3IIudDrv90l-FTmFCoN2sWN-jq11fPwFUXyC3_
                    entry:
                      - fullUrl: >-
                          https://api.haau3.com/v1/fhir/r4/Organization/Organization-0061f2ad-76fd-4eb3-906f-43bac6d6ea2b
                        resource:
                          resourceType: Organization
                          id: Organization-0061f2ad-76fd-4eb3-906f-43bac6d6ea2b
                          meta:
                            versionId: '1'
                            lastUpdated: '2026-10-14T20:49:01.200431720Z'
                            profile:
                              - >-
                                http://hl7.org/fhir/us/ndh/StructureDefinition/ndh-Organization
                          extension:
                            - url: >-
                                http://hl7.org/fhir/us/ndh/StructureDefinition/base-ext-verification-status
                              valueCodeableConcept:
                                coding:
                                  - system: >-
                                      http://hl7.org/fhir/us/ndh/CodeSystem/NdhVerificationStatusCS
                                    code: complete
                                    display: Complete
                          active: true
                          type:
                            - text: ntwk
                          name: FAMILY HEALTH ALLIANCE MEDICAL GROUP
                        search:
                          mode: match
                      - fullUrl: >-
                          https://api.haau3.com/v1/fhir/r4/Organization/Organization-0379b9dd-f3f2-4680-aeee-402fcbcace00
                        resource:
                          resourceType: Organization
                          id: Organization-0379b9dd-f3f2-4680-aeee-402fcbcace00
                          meta:
                            versionId: '1'
                            lastUpdated: '2026-10-14T20:49:01.202445008Z'
                            profile:
                              - >-
                                http://hl7.org/fhir/us/ndh/StructureDefinition/ndh-Organization
                          extension:
                            - url: >-
                                http://hl7.org/fhir/us/ndh/StructureDefinition/base-ext-verification-status
                              valueCodeableConcept:
                                coding:
                                  - system: >-
                                      http://hl7.org/fhir/us/ndh/CodeSystem/NdhVerificationStatusCS
                                    code: complete
                                    display: Complete
                          active: true
                          type:
                            - text: ntwk
                          name: ATLAS HEALTHCARE PHYSICIANS
                        search:
                          mode: match
          headers:
            X-Request-Id:
              $ref: '#/components/headers/XRequestId'
            X-Correlation-Id:
              $ref: '#/components/headers/XCorrelationId'
        '400':
          description: >-
            The request named a parameter, identifier system or value this
            service does not serve. Every unsupported parameter is refused by
            name, and none is silently ignored, so a search that returns results
            applied every filter you sent.
          content:
            application/fhir+json:
              schema:
                $ref: '#/components/schemas/OperationOutcome'
          headers:
            X-Request-Id:
              $ref: '#/components/headers/XRequestId'
            X-Correlation-Id:
              $ref: '#/components/headers/XCorrelationId'
        '401':
          $ref: '#/components/responses/FhirUnauthorized'
        '404':
          description: No such resource, or no such interaction on this base.
          content:
            application/fhir+json:
              schema:
                $ref: '#/components/schemas/OperationOutcome'
          headers:
            X-Request-Id:
              $ref: '#/components/headers/XRequestId'
            X-Correlation-Id:
              $ref: '#/components/headers/XCorrelationId'
        '406':
          $ref: '#/components/responses/FhirNotAcceptable'
        '429':
          $ref: '#/components/responses/FhirTooManyRequests'
        '500':
          $ref: '#/components/responses/FhirServerError'
        '502':
          description: >-
            The directory could not be reached, answered in a shape that cannot
            be served, or answered with more than is served at once: a
            `_revinclude` past the directory's 100 records on a page, or an
            answer over 8 MiB. No answer is given: this is never reported as an
            empty result, which would read as 'no such provider'.
          content:
            application/fhir+json:
              schema:
                $ref: '#/components/schemas/OperationOutcome'
          headers:
            X-Request-Id:
              $ref: '#/components/headers/XRequestId'
            X-Correlation-Id:
              $ref: '#/components/headers/XCorrelationId'
        '503':
          description: >-
            The directory is rate limiting requests. Send the request again
            after `Retry-After`. It is also the answer when the API key could
            not be checked just now, with `Retry-After`.
          content:
            application/fhir+json:
              schema:
                $ref: '#/components/schemas/OperationOutcome'
          headers:
            Retry-After:
              description: >-
                Sent when waiting will help: the API key could not be checked
                just now, or the source behind this service is rate limiting
                requests. How many seconds to wait before sending the request
                again.
              schema:
                type: integer
                minimum: 0
            X-Request-Id:
              $ref: '#/components/headers/XRequestId'
            X-Correlation-Id:
              $ref: '#/components/headers/XCorrelationId'
        '504':
          description: The directory did not respond in time.
          content:
            application/fhir+json:
              schema:
                $ref: '#/components/schemas/OperationOutcome'
          headers:
            X-Request-Id:
              $ref: '#/components/headers/XRequestId'
            X-Correlation-Id:
              $ref: '#/components/headers/XCorrelationId'
      x-codeSamples:
        - lang: bash
          label: cURL
          source: >
            curl
            "https://api.haau3.com/v1/fhir/r4/Organization?type=ntwk&_count=2" \
              -H "Authorization: Bearer $HAAU3_API_KEY"
        - lang: typescript
          label: TypeScript
          source: >
            import { Haau3 } from "@haau3/sdk";


            const haau3 = new Haau3(); // reads HAAU3_API_KEY

            const bundle = await haau3.searchOrganization({ type: "ntwk",
            _count: 2 });

            console.log(bundle.entry?.length ?? 0);
        - lang: python
          label: Python
          source: |
            from haau3 import Haau3

            client = Haau3()  # reads HAAU3_API_KEY
            bundle = client.search_organization(type="ntwk", count=2)
            print(len(bundle.get("entry", [])))
        - lang: go
          label: Go
          source: "package main\n\nimport (\n\t\"context\"\n\t\"fmt\"\n\t\"log\"\n\n\t\"github.com/haau3/haau3-go\"\n)\n\nfunc main() {\n\tctx := context.Background()\n\tclient, err := haau3.NewClient() // reads HAAU3_API_KEY\n\tif err != nil {\n\t\tlog.Fatal(err)\n\t}\n\tbundle, err := client.SearchOrganization(ctx, haau3.SearchOrganizationParams{Type: new(\"ntwk\"), Count: new(2)})\n\tif err != nil {\n\t\tlog.Fatal(err)\n\t}\n\tfmt.Println(len(bundle.Entry))\n}\n"
components:
  parameters:
    XRequestId:
      name: X-Request-Id
      in: header
      required: false
      schema:
        type: string
        format: uuid
      description: >-
        An id of your own for this request, as a UUID. It comes back in the
        `X-Correlation-Id` header and is kept with haau3's record of the
        request. Any value that is not a UUID is ignored. See
        https://docs.haau3.com/errors#request-ids.
  schemas:
    Bundle:
      type: object
      description: A FHIR R4 [Bundle](https://hl7.org/fhir/R4/bundle.html).
      properties:
        resourceType:
          type: string
          const: Bundle
        type:
          type: string
        entry:
          type: array
          items:
            type: object
            additionalProperties: true
      required:
        - resourceType
      additionalProperties: true
    OperationOutcome:
      type: object
      description: >-
        A FHIR R4
        [OperationOutcome](https://hl7.org/fhir/R4/operationoutcome.html).
      properties:
        resourceType:
          type: string
          const: OperationOutcome
        issue:
          type: array
          items:
            type: object
            properties:
              severity:
                type: string
                enum:
                  - fatal
                  - error
                  - warning
                  - information
              code:
                type: string
              details:
                type: object
                properties:
                  text:
                    type: string
                additionalProperties: true
              diagnostics:
                type: string
              expression:
                type: array
                items:
                  type: string
            required:
              - severity
              - code
            additionalProperties: true
      required:
        - resourceType
        - issue
  headers:
    XRequestId:
      description: >-
        The id haau3 gave this request, a UUID, on every response. Quote it in a
        question about the response. A problem carries the same id as its
        `instance`.
      schema:
        type: string
        format: uuid
    XCorrelationId:
      description: The `X-Request-Id` you sent, when it was a UUID.
      schema:
        type: string
        format: uuid
  responses:
    FhirUnauthorized:
      description: Missing or invalid API key.
      content:
        application/fhir+json:
          schema:
            $ref: '#/components/schemas/OperationOutcome'
      headers:
        WWW-Authenticate:
          description: >-
            The scheme to authenticate with: `Bearer realm="api.haau3.com"`,
            with `error="invalid_token"` when a key was sent and not recognised.
          schema:
            type: string
        X-Request-Id:
          $ref: '#/components/headers/XRequestId'
        X-Correlation-Id:
          $ref: '#/components/headers/XCorrelationId'
    FhirNotAcceptable:
      description: >-
        The request asked for a format other than JSON (`Accept` or `_format`),
        or for a FHIR release this endpoint does not serve (the `fhirVersion`
        media-type parameter).
      content:
        application/fhir+json:
          schema:
            $ref: '#/components/schemas/OperationOutcome'
      headers:
        X-Request-Id:
          $ref: '#/components/headers/XRequestId'
        X-Correlation-Id:
          $ref: '#/components/headers/XCorrelationId'
    FhirTooManyRequests:
      description: >-
        A limit of the organization's plan was reached: its requests a minute,
        or the Developer plan's requests a month. Send the request again after
        `Retry-After`, which for the monthly limit runs to the 1st of the next
        month (UTC).
      content:
        application/fhir+json:
          schema:
            $ref: '#/components/schemas/OperationOutcome'
      headers:
        Retry-After:
          description: How many seconds to wait before sending the request again.
          schema:
            type: integer
            minimum: 0
        X-Request-Id:
          $ref: '#/components/headers/XRequestId'
        X-Correlation-Id:
          $ref: '#/components/headers/XCorrelationId'
    FhirServerError:
      description: The server failed to process this request.
      content:
        application/fhir+json:
          schema:
            $ref: '#/components/schemas/OperationOutcome'
      headers:
        X-Request-Id:
          $ref: '#/components/headers/XRequestId'
        X-Correlation-Id:
          $ref: '#/components/headers/XCorrelationId'
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      description: >-
        Your platform API key (`haau3_sk_…`), sent as `Authorization: Bearer
        <key>`.

````

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