Lucidworks Embeddings and Classification API

openapi: 3.1.0
info:
  title: Lucidworks Embeddings and Classification API
  description: >-
    The Embeddings and Classification API generates 768-dimensional vector
    encodings using the English Language Model text encoder, returns ranked
    classification labels, exposes custom model predictions, and tokenizes
    inputs by model ID. Use these endpoints to power vector search,
    similarity, and downstream ML pipelines.
  version: '1.0.0'
  contact:
    name: Lucidworks Support
    url: https://lucidworks.com/support
externalDocs:
  description: Lucidworks API Reference
  url: https://doc.lucidworks.com/api-reference
servers:
  - url: https://api.lucidworks.ai
security:
  - bearerAuth: []
tags:
  - name: Embeddings
    description: Generate vector encodings
  - name: Classification
    description: Predict ranked labels
  - name: Tokenization
    description: Tokenize text by model
paths:
  /ai/encode/{modelId}:
    post:
      tags:
        - Embeddings
      summary: Encode text to embedding
      description: Generate a 768-dimensional vector encoding from input text.
      operationId: encodeText
      parameters:
        - name: modelId
          in: path
          required: true
          schema:
            type: string
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/EncodeRequest'
      responses:
        '200':
          description: Embedding vector
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Embedding'
  /ai/classify/{modelId}:
    post:
      tags:
        - Classification
      summary: Classify text
      description: Return ranked labels for the given input text.
      operationId: classifyText
      parameters:
        - name: modelId
          in: path
          required: true
          schema:
            type: string
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/ClassifyRequest'
      responses:
        '200':
          description: Classification result
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ClassifyResponse'
  /ai/predict/{modelId}:
    post:
      tags:
        - Classification
      summary: Custom model prediction
      description: Invoke a custom deployed model for prediction.
      operationId: customPrediction
      parameters:
        - name: modelId
          in: path
          required: true
          schema:
            type: string
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              additionalProperties: true
      responses:
        '200':
          description: Prediction result
          content:
            application/json:
              schema:
                type: object
                additionalProperties: true
  /ai/tokenize/{modelId}:
    post:
      tags:
        - Tokenization
      summary: Tokenize text
      description: Return token IDs and tokens for the input text.
      operationId: tokenize
      parameters:
        - name: modelId
          in: path
          required: true
          schema:
            type: string
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
                - input
              properties:
                input:
                  type: string
      responses:
        '200':
          description: Tokens
          content:
            application/json:
              schema:
                type: object
                properties:
                  tokens:
                    type: array
                    items:
                      type: string
                  ids:
                    type: array
                    items:
                      type: integer
components:
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      bearerFormat: JWT
  schemas:
    EncodeRequest:
      type: object
      required:
        - input
      properties:
        input:
          type: string
    Embedding:
      type: object
      properties:
        embedding:
          type: array
          items:
            type: number
        dimensions:
          type: integer
          example: 768
    ClassifyRequest:
      type: object
      required:
        - input
      properties:
        input:
          type: string
        topK:
          type: integer
    ClassifyResponse:
      type: object
      properties:
        labels:
          type: array
          items:
            type: object
            properties:
              label:
                type: string
              score:
                type: number