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

# Look Up a Data User by DUID

> Returns profile and status information for a registered Data User
organisation identified by DUID.

**Intended caller: Data Providers.**

When a Data Provider calls `GET /access-records/{ak}` to verify an
access record, the response includes a `duid` identifying the organisation
that registered the record. Without this endpoint, the Data Provider has
no independent means to confirm that the `duid` belongs to an active,
known organisation — they can only rely on their own bilateral
onboarding records.

This endpoint closes that gap by providing a central directory lookup.
Data Providers **should** call this endpoint as part of first-time
onboarding of a new DUID encountered in a verification response, and
**may** call it periodically to detect status changes (e.g. suspension).

**Authentication:** Bearer token required. Data Providers must obtain
a token via `GET /auth/token` using their own `account_id:secret_key`
credentials, which are provisioned separately from Data User credentials.

**Note on DUID mapping:** The register intentionally does not map DUIDs
to Data Provider platform account IDs — that linkage is the Data
Provider's responsibility, as stated in the `GET /access-records/{ak}`
verification checklist. This endpoint supplies the canonical
human-readable identity (name, status, contact) for the DUID so the
Data Provider can confirm the mapping is correct on their side.




## OpenAPI

````yaml /data-access-register/api/openapi-dar.yaml get /data-users/{duid}
openapi: 3.1.0
info:
  title: Data Access Register
  description: >
    Core APIs for the Central Data Access Register.


    The register records all lawful access to customer energy data by
    Controllers,

    regardless of the legal basis on which that access rests. It is not
    exclusively

    a consent register — legitimate interests, public task, legal obligation,
    and

    contract are all within scope alongside consent-based access.


    **Jurisdiction:** This is a UK-only solution. All Controllers, customers,
    and

    meter points are within Great Britain. The governing data protection
    framework

    is **UK GDPR** and the **Data Protection Act 2018**. EU GDPR does not apply.

    The jurisdiction field is fixed to `GB` and does not need to be supplied.


    ## Purpose


    The register provides a single, auditable source of truth for:


    - **Controllers** — to record and demonstrate the legal basis under which
    they
      access customer meter data.
    - **Data Providers** — to verify that a Controller has a registered, active
    access
      record before releasing data.
    - **Customers** — to view all parties registered as having lawful access to
    their
      meter point, on request via any Controller.

    ## Party Model


    | Party | UK GDPR Role | Description |

    |---|---|---|

    | **Data User** | Processor | Operates the register. Fetches and processes
    meter data on behalf of Controllers. Authenticated via bearer token. |

    | **Controller** | Data Controller | A B2B customer of the Data User. One or
    more Controllers may be registered per access record — sole, joint (Art.
    26), or group (trading name transparency). Bears GDPR accountability for the
    legal basis and its ongoing validity. |

    | **Customer** | Data Subject | The energy customer. Identified by MPxN to
    minimise PII held centrally. |

    | **Data Provider** | Data Source | Holds meter data. Verifies access
    records before releasing data via `GET /access-records/{ak}`. |


    ## Record Structure


    All access records share a single schema — `AccessRecord` — with four
    sections

    aligned to ISO/IEC TS 27560:2023:


    1. **`record-metadata`** — record identifier, creation timestamp, controller
       arrangement (sole, joint, or group), and a reference to the associated
       Identity Record. Present for all records.
    2. **`notice`** — the privacy notice(s) presented to the customer. Present
    only
       for consent-based records; null for all other legal bases. Supports a single
       shared notice (common) or per-controller notices (joint arrangements where
       controllers discharge Art. 13 obligations separately).
    3. **`processing`** — legal basis, purpose, data types, and related
    obligations.
       Present for all records. Per-controller compliance fields (privacy rights URL,
       LIA reference, statutory reference, storage conditions) are held on each
       controller entry within `record-metadata.controller-arrangement`.
    4. **`access-event`** — when and how access was registered or consent was
    obtained;
       current lifecycle state. Present for all records.

    The `notice` and `access-event.consent` sub-object are null for non-consent
    records.

    The `access-event.consent` sub-object is null for non-consent records and
    populated

    for consent records.


    ## Identity Records


    The person-property relationship — who the individual is and their occupancy
    of the

    meter point — is held separately in an **Identity Record**
    (`/identity-records`).

    This keeps PII (MPxN, address, move-in date) and identity verification
    evidence

    out of the access record entirely.


    Each `AccessRecord` carries an `identity-record-ref` (`ir` key) linking it
    to its

    Identity Record. Identity Records are accessible only to authenticated Data
    Users.

    The unauthenticated `GET /access-records/{ak}` endpoint used by Data
    Providers

    never returns PII.


    Identity Records support two re-identification flows to reconnect a
    returning

    customer to an existing record without re-collecting all their details:

    - **Magic link** — a short-lived email link triggers re-identification.

    - **Passkey** — initiates a WebAuthn registration or assertion ceremony.


    ## Legal Basis and Required Fields


    The `processing.legal-basis` value determines which fields within `notice`
    and

    `access-event.consent` are expected:


    | Legal basis | `notice` | `access-event.consent` |

    |---|---|---|

    | `uk-consent`, `uk-explicit-consent` | **Required** | **Required** |

    | All other bases | Must be null | Must be null |


    For legitimate interests records, `lia-reference` should be supplied on the

    lead controller entry within `record-metadata.controller-arrangement`.

    For public task or legal obligation records, `statutory-reference`

    should be supplied on the lead controller entry.


    ## Access Record Lifecycle


    Records are never hard-deleted. All state transitions are recorded with
    timestamps.


    ```

    [ACTIVE] ──revoke──▶ [REVOKED]

    [ACTIVE] ──expiry──▶ [EXPIRED]

    [DISCOVERED] ──claimed──▶ [ACTIVE]

    [DISCOVERED] ──expiry──▶ [EXPIRED]

    ```


    `REVOKED` represents consent withdrawal (consent records) or the Controller

    removing their registration (non-consent records). Data Providers must deny

    access for any record not in `ACTIVE` state with a future (or null) expiry.


    `DISCOVERED` is a sparse, read-only state created by the DCC when it detects

    historic meter data requests from an organisation that has not yet
    registered

    as a Data User. These records are visible to Customers for transparency but

    cannot be used to authorise data release. When the organisation onboards as

    a Data User and registers a full access record for the same MPxN, the

    DISCOVERED record is superseded and transitions to `ACTIVE`.


    ## Authentication


    All endpoints except `GET /access-records/{ak}` require a bearer token from

    `GET /auth/token`. Tokens expire after 7200 seconds.


    ## Versioning


    URI-based versioning. Current version: `v1`.
  version: 0.0.16
  contact:
    name: Auth Energy
    email: contact@auth.energy
    url: https://docs.auth.energy/consent
  license:
    name: Proprietary
servers:
  - url: https://api.central.consent/v1
    description: Production
security: []
tags:
  - name: Identity Records
    description: >
      Endpoints for Data Users to create and manage Identity Records, which hold
      the person-property relationship (MPxN, address, move-in date, identity
      verification evidence) separately from access records. Supports
      re-identification of returning customers via email magic link or WebAuthn
      passkey.
  - name: Re-identification
    description: >-
      Endpoints for initiating and confirming customer re-identification flows.
      Supports magic link, passkey assertion, and passkey registration — both
      for the same Data User (same-DUID) and for a second Data User linking to
      an existing Identity Record created by another Data User (cross-DUID). In
      the cross-DUID flow the `ir` key is never exposed to the initiating Data
      User — the register resolves it internally after the customer completes
      the challenge.
  - name: Authentication
    description: Obtain bearer tokens for authenticated endpoints.
  - name: Data Users
    description: >
      Endpoints for Data Users (Processors) to register and manage access
      records on behalf of their Controller customers.
  - name: Data Providers
    description: >
      Endpoints for Data Providers (EDPs) to verify access records and look up
      registered Data User organisations before releasing meter data. Includes
      access record verification via access key and Data User directory lookup
      by DUID, allowing EDPs to confirm both that a specific record is active
      and that the organisation behind it is in good standing.
  - name: DCC
    description: >
      Endpoints restricted to Smart DCC system credentials. Covers two
      responsibilities: (1) submitting discovered access records derived from
      historic meter transaction logs — sparse, read-only records that surface
      to customers for transparency but cannot authorise data release,
      superseded when the organisation registers as a Data User; and (2)
      submitting Change of Tenancy events, which trigger `tenancy.change`
      webhooks to all Data Users with active access records on the affected
      MPxN.
  - name: Customer Portal
    description: >
      The centralised Customer Consent Portal is a standalone web service at
      https://portal.central.consent. It has no API endpoints — Data Users link
      customers to the portal via a plain URL carrying `ir` or `mpxn` and an
      optional `return` parameter. The portal authenticates the customer
      directly using the re-identification mechanisms on their Identity Record
      (passkey, magic link, or supplier OAuth fallback). This tag documents the
      portal behaviour and the `consent.withdrawal` webhook it fires on
      revocation.
  - name: Webhooks
    description: >
      Endpoints for Controllers to register and manage webhook subscriptions.
      The register dispatches event payloads to registered callback URLs when
      consent records are approaching expiry or when a Change of Tenancy is
      recorded against an MPxN with active access records.
paths:
  /data-users/{duid}:
    get:
      tags:
        - Data Providers
      summary: Look Up a Data User by DUID
      description: >
        Returns profile and status information for a registered Data User

        organisation identified by DUID.


        **Intended caller: Data Providers.**


        When a Data Provider calls `GET /access-records/{ak}` to verify an

        access record, the response includes a `duid` identifying the
        organisation

        that registered the record. Without this endpoint, the Data Provider has

        no independent means to confirm that the `duid` belongs to an active,

        known organisation — they can only rely on their own bilateral

        onboarding records.


        This endpoint closes that gap by providing a central directory lookup.

        Data Providers **should** call this endpoint as part of first-time

        onboarding of a new DUID encountered in a verification response, and

        **may** call it periodically to detect status changes (e.g. suspension).


        **Authentication:** Bearer token required. Data Providers must obtain

        a token via `GET /auth/token` using their own `account_id:secret_key`

        credentials, which are provisioned separately from Data User
        credentials.


        **Note on DUID mapping:** The register intentionally does not map DUIDs

        to Data Provider platform account IDs — that linkage is the Data

        Provider's responsibility, as stated in the `GET /access-records/{ak}`

        verification checklist. This endpoint supplies the canonical

        human-readable identity (name, status, contact) for the DUID so the

        Data Provider can confirm the mapping is correct on their side.
      operationId: getDataUser
      parameters:
        - name: duid
          in: path
          required: true
          description: >
            The Data User identifier to look up. Format: `duid_` followed by 24
            lowercase hex characters.
          schema:
            $ref: '#/components/schemas/DataUserId'
      responses:
        '200':
          description: Data User found and returned.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/GetDataUserResponse'
              example:
                response:
                  resource: /v1/data-users/duid_691df0c788ca043403b7fa90
                  timestamp: '2026-03-18T10:00:00Z'
                  transaction-id: tid_abc123def456abc123def456
                data-user:
                  duid: duid_691df0c788ca043403b7fa90
                  display-name: Bright Energy Services Ltd
                  status: active
                  registered-at: '2024-01-15T09:00:00Z'
                  contact-url: https://bright-energy.com/contact
                  data-types-supported:
                    - HH-CONSUMPTION
                    - HH-EXPORT
                    - TARIFF-IMPORT
        '401':
          $ref: '#/components/responses/Unauthorised'
        '404':
          description: >
            No Data User with the supplied DUID exists in the register. Data
            Providers receiving an unknown DUID in a verification response
            should treat this as a signal to deny data release and raise a
            support query.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '500':
          $ref: '#/components/responses/InternalServerError'
      security:
        - bearerAuth: []
components:
  schemas:
    DataUserId:
      type: string
      pattern: ^duid_[0-9a-f]{24}$
      description: >
        Unique identifier for a registered Data User organisation, issued by the
        register at onboarding.
      example: duid_691df0c788ca043403b7fa90
    GetDataUserResponse:
      type: object
      properties:
        response:
          $ref: '#/components/schemas/ResponseMetadata'
        data-user:
          $ref: '#/components/schemas/DataUserProfile'
      required:
        - response
        - data-user
    ErrorResponse:
      type: object
      properties:
        response:
          $ref: '#/components/schemas/ResponseMetadata'
        errors:
          type: array
          minItems: 1
          items:
            $ref: '#/components/schemas/ErrorDetail'
      required:
        - response
        - errors
    ResponseMetadata:
      type: object
      properties:
        resource:
          type: string
          example: /v1/access-records/ak_691df0c788ca043403b7fa90
        timestamp:
          type: string
          format: date-time
          example: '2026-03-11T12:00:00Z'
        transaction-id:
          type: string
          description: >-
            Unique identifier for this request/response pair. Quote in support
            enquiries.
          example: tid_691df0c788ca043403b7fa90
      required:
        - resource
        - timestamp
        - transaction-id
    DataUserProfile:
      type: object
      description: >
        Public directory entry for a registered Data User organisation. Returned
        by `GET /data-users/{duid}`.
      properties:
        duid:
          $ref: '#/components/schemas/DataUserId'
        display-name:
          type: string
          maxLength: 255
          description: Trading name of the Data User organisation.
          example: Bright Energy Services Ltd
        status:
          $ref: '#/components/schemas/DataUserStatus'
        registered-at:
          type: string
          format: date-time
          description: UTC timestamp when this Data User was registered in the directory.
          example: '2024-01-15T09:00:00Z'
        suspended-at:
          type: string
          format: date-time
          nullable: true
          description: >
            UTC timestamp of the most recent suspension. Null if the Data User
            has never been suspended.
          example: null
        contact-url:
          type: string
          format: uri
          description: >
            URL of the Data User's public contact or support page. Allows Data
            Providers to make direct enquiries about specific access records.
          example: https://bright-energy.com/contact
        data-types-supported:
          description: >
            The data types this Data User is authorised to register access
            records for. Data Providers may use this to validate that a data
            type appearing in an access record is within the Data User's
            authorised scope.
          allOf:
            - $ref: '#/components/schemas/DataType'
      required:
        - duid
        - display-name
        - status
        - registered-at
        - contact-url
        - data-types-supported
    ErrorDetail:
      type: object
      properties:
        error-code:
          type: string
          example: VAL001
        message:
          type: string
          example: Field 'mpxn' does not match the required pattern.
      required:
        - error-code
        - message
    DataUserStatus:
      type: string
      description: |
        Operational status of the Data User registration.

        - `active` — the Data User is in good standing and access records it has
          registered are considered valid.
        - `suspended` — the Data User's registration has been suspended (e.g.
          pending a compliance review). Data Providers **must** deny data release
          for all access records registered under a suspended Data User until
          status returns to `active`.
        - `terminated` — the Data User's registration has been permanently
          withdrawn. All associated access records are considered invalid.
      enum:
        - active
        - suspended
        - terminated
    DataType:
      type: array
      minItems: 1
      description: One or more energy data categories covered by this access record.
      items:
        type: string
        enum:
          - HH-CONSUMPTION
          - HH-EXPORT
          - MTH-CONSUMPTION
          - MTH-EXPORT
          - ANNUAL-CONSUMPTION
          - ANNUAL-EXPORT
          - TARIFF-IMPORT
          - TARIFF-EXPORT
  responses:
    Unauthorised:
      description: Missing or invalid bearer token.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorResponse'
    InternalServerError:
      description: An unexpected server-side error occurred.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorResponse'
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      bearerFormat: JWT
      description: >-
        JWT from `GET /auth/token`. Pass as `Authorization: Bearer <token>`.
        Expires after 7200s.

````