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

# List connection keys

> Returns every connection key that the KODE ontology defines, sorted by key. Use it to find the key of a relationship between two devices.

A connection key names a relationship between devices, such as a device that supplies air to another. The list is the same for the whole organization. To see which keys a given canonical type accepts, and in which direction, call [List connections for a canonical type](https://docs.kodelabs.com/products/kode-api/api-reference/ontology/list-connections-for-a-canonical-type.md).

The order is fixed, so `asc` and `dsc` have no effect.


## OpenAPI

````yaml /openapi/kode-api.yaml get /api/v1/ontology/connections
openapi: 3.1.0
info:
  title: KODE API
  version: 1.0.0
  summary: Programmatic access to KODE OS resources and operations.
  description: >
    Use the KODE API to work with buildings, data sources, connectors, devices,
    points, virtual devices,

    timeseries data, schedules, the ontology, templating, mass writes, spaces,
    space assignments, tenants, meters, users, actions,

    and AssetOps work orders.
  license:
    name: Proprietary
    identifier: LicenseRef-Proprietary
servers:
  - url: https://api.kodelabs.com/kodeos
    description: KODE API
security:
  - bearerAuth: []
tags:
  - name: Authentication
    description: OAuth 2.0 discovery, token, and revocation endpoints.
  - name: Buildings
    description: Buildings and their areas.
  - name: Data sources
    description: Data sources connected to a building.
  - name: Devices
    description: Devices and their points.
  - name: Points
    description: Point queries and point writes.
  - name: Timeseries
    description: Current and historical point values.
  - name: Actions
    description: Actions exposed by building data sources.
  - name: Work orders
    description: AssetOps work orders, lookups, comments, and attachments.
  - name: Connectors
    description: KODE API connectors and the devices and points ingested through them.
  - name: Schedules
    description: Schedules discovered on building data sources.
  - name: Templating
    description: Apply ontology templates to groups of points.
  - name: Virtual devices
    description: Virtual devices that group points from other devices.
  - name: Ontology
    description: Canonical types, fields, units, and connections of the KODE ontology.
  - name: Users
    description: Users of the organization and their app access.
  - name: Mass write
    description: Write values to many points across buildings, and follow each run.
  - name: Spaces
    description: Levels and space units of a building, and the meters located in them.
  - name: Space assignments
    description: Assign tenants to leasable spaces of a building for a period.
  - name: Tenants
    description: Tenants of a building, the people or companies that lease its spaces.
  - name: Meters
    description: >-
      Meters of a building, their space assignments, parent and child links, and
      readings.
paths:
  /api/v1/ontology/connections:
    get:
      tags:
        - Ontology
      summary: List connection keys
      description: >-
        Returns every connection key that the KODE ontology defines, sorted by
        key. Use it to find the key of a relationship between two devices.
      operationId: listOntologyConnectionKeys
      parameters:
        - name: asc
          in: query
          schema:
            type: string
          description: Not used. The order is fixed.
        - name: dsc
          in: query
          schema:
            type: string
            default: _id
          description: Not used. The order is fixed.
        - name: limit
          in: query
          schema:
            type: integer
            format: int32
            maximum: 200
            minimum: 1
            default: 50
          description: >-
            Maximum number of keys to return, from `1` to `200`. The default is
            `50`.
        - name: page
          in: query
          schema:
            type: integer
            format: int32
            minimum: 1
            default: 1
          description: Page number to return. The first page is `1`.
        - name: q
          in: query
          schema:
            type: string
          description: >-
            Return only keys that contain this text. The match is
            case-insensitive.
      responses:
        '200':
          description: A page of connection keys, as a list of strings.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/PaginatedEntityString'
        '400':
          description: '`page` or `limit` is not valid.'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/Forbidden'
        '429':
          $ref: '#/components/responses/TooManyRequests'
components:
  schemas:
    PaginatedEntityString:
      type: object
      properties:
        data:
          type: array
          items:
            type: string
        page:
          type: integer
          format: int32
        limit:
          type: integer
          format: int32
        pageCount:
          type: integer
          format: int32
        itemCount:
          type: integer
          format: int32
  responses:
    Unauthorized:
      description: The access token is missing, invalid, or expired. Request a new token.
    Forbidden:
      description: The service account lacks permission for this building or operation.
    TooManyRequests:
      description: >-
        A rate-limit window is exhausted. Wait, then retry with increasing
        delays.
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      bearerFormat: JWT
      description: >
        Paste an access token from [Create an access
        token](/products/kode-api/api-reference/authentication/create-an-access-token).
        Tokens expire, so request a new one if you receive `401`.

````

This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.