Kubernetes Services EndpointSlices API

openapi: 3.1.0
info:
  title: Kubernetes Services Kubernetes EndpointSlices API
  description: The Kubernetes EndpointSlices API tracks the IP addresses, ports, readiness, and topology information for Pods backing a Service. EndpointSlices replaced the older Endpoints API to improve scalability for large clusters with thousands of pods. A single Service may be backed by multiple EndpointSlices, and the EndpointSlice controller automatically manages their lifecycle in response to pod and Service changes.
  version: v1.32.0
  contact:
    name: Kubernetes Community
    url: https://kubernetes.io/community/
  termsOfService: https://www.apache.org/licenses/LICENSE-2.0
servers:
- url: https://kubernetes.default.svc
  description: In-cluster Kubernetes API Server
security:
- bearerAuth: []
- clientCertificate: []
tags:
- name: EndpointSlices
  description: EndpointSlice resources tracking IP addresses, ports, and readiness of pods backing a Service, with topology-aware routing support.
paths:
  /apis/discovery.k8s.io/v1/namespaces/{namespace}/endpointslices:
    get:
      operationId: listNamespacedEndpointSlices
      summary: Kubernetes Services List EndpointSlices in a namespace
      description: Returns a list of all EndpointSlices in the specified namespace. Each EndpointSlice contains up to 1000 endpoints. Use the kubernetes.io/service-name label selector to retrieve slices for a specific Service.
      tags:
      - EndpointSlices
      parameters:
      - $ref: '#/components/parameters/NamespaceParam'
      - $ref: '#/components/parameters/LabelSelector'
      - $ref: '#/components/parameters/FieldSelector'
      - $ref: '#/components/parameters/Limit'
      - $ref: '#/components/parameters/Continue'
      - $ref: '#/components/parameters/Watch'
      responses:
        '200':
          description: List of EndpointSlice objects
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/EndpointSliceList'
        '401':
          $ref: '#/components/responses/Unauthorized'
    post:
      operationId: createNamespacedEndpointSlice
      summary: Kubernetes Services Create an EndpointSlice
      description: Creates a new EndpointSlice in the specified namespace. EndpointSlices are typically managed by the EndpointSlice controller; manual creation is used for custom service implementations. The kubernetes.io/service-name label must be set to associate the slice with a Service.
      tags:
      - EndpointSlices
      parameters:
      - $ref: '#/components/parameters/NamespaceParam'
      - $ref: '#/components/parameters/DryRun'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/EndpointSlice'
      responses:
        '201':
          description: EndpointSlice created
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/EndpointSlice'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
  /apis/discovery.k8s.io/v1/namespaces/{namespace}/endpointslices/{name}:
    get:
      operationId: getNamespacedEndpointSlice
      summary: Kubernetes Services Get an EndpointSlice
      description: Returns the specified EndpointSlice including its address type, endpoints with IP addresses and readiness conditions, and port definitions.
      tags:
      - EndpointSlices
      parameters:
      - $ref: '#/components/parameters/NamespaceParam'
      - $ref: '#/components/parameters/NameParam'
      responses:
        '200':
          description: EndpointSlice details
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/EndpointSlice'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
    put:
      operationId: replaceNamespacedEndpointSlice
      summary: Kubernetes Services Replace an EndpointSlice
      description: Replaces the full specification of the specified EndpointSlice. Used by custom endpoint controllers to update endpoint addresses and readiness conditions.
      tags:
      - EndpointSlices
      parameters:
      - $ref: '#/components/parameters/NamespaceParam'
      - $ref: '#/components/parameters/NameParam'
      - $ref: '#/components/parameters/DryRun'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/EndpointSlice'
      responses:
        '200':
          description: EndpointSlice updated
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/EndpointSlice'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
    patch:
      operationId: patchNamespacedEndpointSlice
      summary: Kubernetes Services Patch an EndpointSlice
      description: Applies a partial update to the specified EndpointSlice. Used to update individual endpoint readiness conditions or topology hints without replacing the entire slice.
      tags:
      - EndpointSlices
      parameters:
      - $ref: '#/components/parameters/NamespaceParam'
      - $ref: '#/components/parameters/NameParam'
      requestBody:
        required: true
        content:
          application/merge-patch+json:
            schema:
              type: object
      responses:
        '200':
          description: EndpointSlice patched
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/EndpointSlice'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
    delete:
      operationId: deleteNamespacedEndpointSlice
      summary: Kubernetes Services Delete an EndpointSlice
      description: Deletes the specified EndpointSlice. The EndpointSlice controller will recreate a replacement slice if the Service still has backing pods.
      tags:
      - EndpointSlices
      parameters:
      - $ref: '#/components/parameters/NamespaceParam'
      - $ref: '#/components/parameters/NameParam'
      responses:
        '200':
          description: EndpointSlice deleted
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/EndpointSlice'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
  /apis/discovery.k8s.io/v1/endpointslices:
    get:
      operationId: listEndpointSlicesAllNamespaces
      summary: Kubernetes Services List EndpointSlices across all namespaces
      description: Returns all EndpointSlice objects cluster-wide. Useful for network visibility tools and load balancer implementations that need to enumerate all service endpoints across the cluster.
      tags:
      - EndpointSlices
      parameters:
      - $ref: '#/components/parameters/LabelSelector'
      - $ref: '#/components/parameters/FieldSelector'
      - $ref: '#/components/parameters/Limit'
      - $ref: '#/components/parameters/Watch'
      responses:
        '200':
          description: List of EndpointSlices across all namespaces
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/EndpointSliceList'
        '401':
          $ref: '#/components/responses/Unauthorized'
components:
  schemas:
    EndpointPort:
      type: object
      description: A network port definition shared by all endpoints in the slice. An EndpointSlice may have up to 100 ports.
      properties:
        name:
          type: string
          description: Port name. Must match a port name in the parent Service. Must be unique within the ports list.
          maxLength: 15
        port:
          type: integer
          minimum: 1
          maximum: 65535
          description: Port number.
        protocol:
          type: string
          enum:
          - TCP
          - UDP
          - SCTP
          description: Network protocol. Defaults to TCP.
          default: TCP
        appProtocol:
          type: string
          description: Application-layer protocol hint for this port.
    EndpointSliceList:
      type: object
      description: A list of EndpointSlice objects.
      required:
      - items
      properties:
        apiVersion:
          type: string
        kind:
          type: string
          const: EndpointSliceList
        metadata:
          $ref: '#/components/schemas/ListMeta'
        items:
          type: array
          items:
            $ref: '#/components/schemas/EndpointSlice'
    EndpointSlice:
      type: object
      description: An EndpointSlice represents a subset of the endpoints that implement a Service. For a given Service, multiple EndpointSlices may exist, and together they represent all the pods selected by the Service. The kubernetes.io/service-name label links slices to their Service.
      required:
      - addressType
      - endpoints
      properties:
        apiVersion:
          type: string
          const: discovery.k8s.io/v1
        kind:
          type: string
          const: EndpointSlice
        metadata:
          $ref: '#/components/schemas/ObjectMeta'
        addressType:
          type: string
          enum:
          - IPv4
          - IPv6
          description: Address type of endpoints in this slice. All endpoints in a single slice must share the same address type.
        endpoints:
          type: array
          description: List of unique endpoints in this slice. Up to 1000 endpoints per slice.
          maxItems: 1000
          items:
            $ref: '#/components/schemas/Endpoint'
        ports:
          type: array
          description: Network ports exposed by each endpoint in the slice.
          maxItems: 100
          items:
            $ref: '#/components/schemas/EndpointPort'
    EndpointHints:
      type: object
      description: Routing hints that guide topology-aware routing decisions, directing clients to geographically or logically proximate endpoints.
      properties:
        forZones:
          type: array
          description: Zones that should prefer routing to this endpoint.
          items:
            type: object
            properties:
              name:
                type: string
                description: Name of the zone (e.g. us-east-1a).
        forNodes:
          type: array
          description: Nodes that should prefer routing to this endpoint.
          items:
            type: object
            properties:
              name:
                type: string
                description: Name of the node.
    EndpointConditions:
      type: object
      description: Conditions describing the current state of an endpoint, used by consumers to determine whether the endpoint should receive traffic.
      properties:
        ready:
          type: boolean
          description: Whether the endpoint is ready to accept traffic. Pods that have not yet passed readiness probes have ready=false.
        serving:
          type: boolean
          description: Whether the endpoint is capable of serving requests even if not yet ready. True for pods that are in the process of terminating.
        terminating:
          type: boolean
          description: Whether the endpoint is being gracefully terminated. Allows consumers to complete in-flight requests to terminating pods.
    ObjectMeta:
      type: object
      description: Standard Kubernetes object metadata.
      properties:
        name:
          type: string
          description: Name of the object.
        namespace:
          type: string
          description: Namespace of the object.
        uid:
          type: string
          description: Unique server-assigned identifier.
        resourceVersion:
          type: string
          description: Internal version string.
        creationTimestamp:
          type: string
          format: date-time
          description: Creation timestamp.
        labels:
          type: object
          additionalProperties:
            type: string
          description: Label key-value pairs. The kubernetes.io/service-name label identifies the Service this slice belongs to.
        annotations:
          type: object
          additionalProperties:
            type: string
          description: Non-identifying metadata.
    Endpoint:
      type: object
      description: A single network endpoint representing a pod IP address, its readiness conditions, and optional topology information for advanced routing.
      required:
      - addresses
      properties:
        addresses:
          type: array
          description: Canonical IP addresses of this endpoint, in IPv4 or IPv6 format. Between 1 and 100 addresses per endpoint.
          minItems: 1
          maxItems: 100
          items:
            type: string
        conditions:
          $ref: '#/components/schemas/EndpointConditions'
        hostname:
          type: string
          description: DNS hostname for this endpoint. Used by headless services to generate per-pod DNS records.
        nodeName:
          type: string
          description: Node on which this endpoint resides.
        zone:
          type: string
          description: Availability zone where the endpoint is located, used for topology-aware routing.
        targetRef:
          type: object
          description: Reference to the Kubernetes object backing this endpoint.
          properties:
            apiVersion:
              type: string
            kind:
              type: string
            namespace:
              type: string
            name:
              type: string
            uid:
              type: string
        hints:
          $ref: '#/components/schemas/EndpointHints'
    Status:
      type: object
      description: Error or result status.
      properties:
        code:
          type: integer
        message:
          type: string
        reason:
          type: string
        status:
          type: string
          enum:
          - Success
          - Failure
    ListMeta:
      type: object
      description: Metadata for list responses.
      properties:
        resourceVersion:
          type: string
        continue:
          type: string
        remainingItemCount:
          type: integer
  parameters:
    DryRun:
      name: dryRun
      in: query
      description: If 'All', validates without persisting.
      schema:
        type: string
        enum:
        - All
    Continue:
      name: continue
      in: query
      description: Pagination continuation token.
      schema:
        type: string
    Watch:
      name: watch
      in: query
      description: If true, stream watch events.
      schema:
        type: boolean
    NameParam:
      name: name
      in: path
      required: true
      description: Name of the EndpointSlice resource.
      schema:
        type: string
    LabelSelector:
      name: labelSelector
      in: query
      description: Label selector expression. Use kubernetes.io/service-name=<svc> to retrieve slices for a specific Service.
      schema:
        type: string
    FieldSelector:
      name: fieldSelector
      in: query
      description: Field selector to filter resources.
      schema:
        type: string
    NamespaceParam:
      name: namespace
      in: path
      required: true
      description: Namespace name to scope the request.
      schema:
        type: string
    Limit:
      name: limit
      in: query
      description: Maximum number of items to return.
      schema:
        type: integer
        minimum: 1
  responses:
    BadRequest:
      description: Bad request
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Status'
    NotFound:
      description: Not found
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Status'
    Unauthorized:
      description: Unauthorized
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Status'
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      bearerFormat: JWT
      description: Kubernetes service account or user bearer token.
    clientCertificate:
      type: mutualTLS
      description: Client TLS certificate signed by the cluster CA.
externalDocs:
  description: Kubernetes EndpointSlice API Reference
  url: https://kubernetes.io/docs/reference/kubernetes-api/service-resources/endpoint-slice-v1/