Contextual AI

Contextual AI Rerank API

Instruction-following reranking of retrieved passages.

Documentation GitHub OpenAPI

Operations 1

POST /rerank Rerank #

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OpenAPI Specification

openapi: 3.2.0
info:
  title: Contextual AI Platform Agents Rerank API
  description: REST API for the Contextual AI enterprise RAG platform. Provides agents (create / query grounded RAG agents), datastores and documents (ingest and manage the knowledge corpus), and standalone component APIs - Generate (grounded generation with the GLM), Rerank (instruction-following reranker), Parse (document parsing into AI-ready markdown), and LMUnit (natural-language unit-test evaluation). All endpoints authenticate with a Bearer API key.
  termsOfService: https://contextual.ai/terms-of-service/
  contact:
    name: Contextual AI Support
    url: https://docs.contextual.ai
    email: support@contextual.ai
  version: '1.0'
servers:
- url: https://api.contextual.ai/v1
  description: Contextual AI production API
security:
- bearerAuth: []
tags:
- name: Rerank
  description: Instruction-following reranking of retrieved passages.
paths:
  /rerank:
    post:
      operationId: rerank
      tags:
      - Rerank
      summary: Rerank
      description: Rerank a set of documents against a query using the instruction-following reranker. Optionally steer ranking with a natural-language instruction.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/RerankRequest'
      responses:
        '200':
          description: Reranked results.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/RerankResponse'
        '422':
          $ref: '#/components/responses/ValidationError'
components:
  schemas:
    HTTPValidationError:
      type: object
      properties:
        detail:
          type: array
          items:
            $ref: '#/components/schemas/ValidationErrorDetail'
    RerankRequest:
      type: object
      required:
      - query
      - documents
      - model
      properties:
        query:
          type: string
        documents:
          type: array
          items:
            type: string
        model:
          type: string
          enum:
          - ctxl-rerank-v2-instruct-multilingual
          - ctxl-rerank-v2-instruct-multilingual-mini
          - ctxl-rerank-v1-instruct
        top_n:
          type: integer
          minimum: 1
        instruction:
          type: string
          description: Natural-language directive steering the ranking.
        metadata:
          type: array
          items:
            type: string
          description: Per-document metadata, matching the documents array length.
    ValidationErrorDetail:
      type: object
      properties:
        loc:
          type: array
          items:
            oneOf:
            - type: string
            - type: integer
        msg:
          type: string
        type:
          type: string
    RerankResponse:
      type: object
      properties:
        results:
          type: array
          items:
            type: object
            properties:
              index:
                type: integer
              relevance_score:
                type: number
                format: double
  responses:
    ValidationError:
      description: Validation error.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/HTTPValidationError'
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      description: Contextual AI API key supplied as a Bearer token.