kapa.ai Search and Retrieval API

openapi: 3.0.1
info:
  title: kapa.ai Query API
  description: >-
    REST API for the kapa.ai answer platform. Ask a project's kapa.ai instance
    questions and receive retrieval-augmented answers with sources, run threaded
    multi-turn conversations (standard and streamed), perform semantic retrieval
    and keyword search against ingested knowledge sources, submit feedback, and
    read project, integration, source, and analytics data. All requests are
    authenticated with an X-API-KEY header.
  termsOfService: https://www.kapa.ai/content/terms-of-service
  contact:
    name: kapa.ai Support
    url: https://docs.kapa.ai
  version: '1.0'
servers:
  - url: https://api.kapa.ai
    description: kapa.ai production API
security:
  - ApiKeyAuth: []
tags:
  - name: Chat
    description: Ask questions and create threads.
  - name: Threads
    description: List, retrieve, and continue conversations.
  - name: Retrieval
    description: Semantic retrieval and keyword search.
  - name: Feedback
    description: Submit reactions on answers.
  - name: Projects
    description: Projects, integrations, and sources.
  - name: Analytics
    description: Activity, coverage gaps, and top questions.
paths:
  /query/v1/projects/{project_id}/chat:
    post:
      operationId: chat
      tags:
        - Chat
      summary: Chat
      description: >-
        Ask the project's kapa.ai instance a question. Creates a new Thread and
        returns the retrieval-augmented answer with relevant sources.
      parameters:
        - $ref: '#/components/parameters/ProjectId'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/ChatRequest'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ChatResponse'
        '401':
          $ref: '#/components/responses/Unauthorized'
  /query/v1/projects/{project_id}/chat/stream:
    post:
      operationId: chatStream
      tags:
        - Chat
      summary: Chat streamed
      description: >-
        Streamed variant of chat. The answer is delivered incrementally as
        chunks delimited by the Unicode record separator character (U+241E),
        so partial answers can be rendered as they are generated.
      parameters:
        - $ref: '#/components/parameters/ProjectId'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/ChatRequest'
      responses:
        '200':
          description: A stream of answer chunks delimited by U+241E.
          content:
            text/plain:
              schema:
                type: string
        '401':
          $ref: '#/components/responses/Unauthorized'
  /query/v1/projects/{project_id}/chat/custom:
    post:
      operationId: chatCustom
      tags:
        - Chat
      summary: Custom chat
      description: >-
        Chat using caller-supplied context instead of (or in addition to) the
        project's ingested knowledge sources.
      parameters:
        - $ref: '#/components/parameters/ProjectId'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CustomChatRequest'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ChatResponse'
        '401':
          $ref: '#/components/responses/Unauthorized'
  /query/v1/threads/{thread_id}/chat:
    post:
      operationId: chatInThread
      tags:
        - Threads
      summary: Chat in thread
      description: >-
        Ask a follow-up question within an existing Thread, preserving the
        conversation context.
      parameters:
        - $ref: '#/components/parameters/ThreadId'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/ChatRequest'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ChatResponse'
        '401':
          $ref: '#/components/responses/Unauthorized'
  /query/v1/threads/{thread_id}/chat/stream:
    post:
      operationId: chatInThreadStream
      tags:
        - Threads
      summary: Chat in thread streamed
      description: >-
        Streamed follow-up question within an existing Thread. Chunks are
        delimited by the Unicode record separator character (U+241E).
      parameters:
        - $ref: '#/components/parameters/ThreadId'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/ChatRequest'
      responses:
        '200':
          description: A stream of answer chunks delimited by U+241E.
          content:
            text/plain:
              schema:
                type: string
        '401':
          $ref: '#/components/responses/Unauthorized'
  /query/v1/threads/{thread_id}:
    get:
      operationId: getThread
      tags:
        - Threads
      summary: Retrieve a thread
      description: Retrieve a single Thread object and its messages.
      parameters:
        - $ref: '#/components/parameters/ThreadId'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Thread'
        '401':
          $ref: '#/components/responses/Unauthorized'
  /query/v1/projects/{project_id}/threads:
    get:
      operationId: listThreads
      tags:
        - Threads
      summary: List threads
      description: List Thread objects for a project.
      parameters:
        - $ref: '#/components/parameters/ProjectId'
        - $ref: '#/components/parameters/PageSize'
        - $ref: '#/components/parameters/PageNumber'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ThreadList'
        '401':
          $ref: '#/components/responses/Unauthorized'
  /query/v1/feedback:
    post:
      operationId: upsertFeedback
      tags:
        - Feedback
      summary: Upsert feedback
      description: >-
        Submit or update feedback (a reaction and optional comment) on a
        specific question/answer using its question_answer_id.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/FeedbackRequest'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/FeedbackResponse'
        '401':
          $ref: '#/components/responses/Unauthorized'
  /query/v1/projects/{project_id}/retrieval:
    post:
      operationId: retrieval
      tags:
        - Retrieval
      summary: Retrieval
      description: >-
        Semantic retrieval against the project's ingested knowledge sources
        without LLM generation. Returns the most relevant chunks in descending
        order of relevance, for use as context for external LLMs and agents.
      parameters:
        - $ref: '#/components/parameters/ProjectId'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/RetrievalRequest'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/RetrievalResponse'
        '401':
          $ref: '#/components/responses/Unauthorized'
  /query/v1/projects/{project_id}/search:
    get:
      operationId: search
      tags:
        - Retrieval
      summary: Search (deprecated)
      description: >-
        Deprecated fast keyword-based search across the project's knowledge
        sources. Use the retrieval endpoint for semantic search.
      deprecated: true
      parameters:
        - $ref: '#/components/parameters/ProjectId'
        - name: query
          in: query
          required: true
          schema:
            type: string
          description: The search query string.
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/RetrievalResponse'
        '401':
          $ref: '#/components/responses/Unauthorized'
  /org/v1/projects/{project_id}:
    get:
      operationId: getProject
      tags:
        - Projects
      summary: Retrieve a project
      description: Retrieve a single project by id.
      parameters:
        - $ref: '#/components/parameters/ProjectId'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Project'
        '401':
          $ref: '#/components/responses/Unauthorized'
  /query/v1/projects/{project_id}/integrations:
    get:
      operationId: listIntegrations
      tags:
        - Projects
      summary: List all integrations
      description: List the integrations configured for a project.
      parameters:
        - $ref: '#/components/parameters/ProjectId'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/IntegrationList'
        '401':
          $ref: '#/components/responses/Unauthorized'
  /ingestion/v1/projects/{project_id}/sources:
    get:
      operationId: listSources
      tags:
        - Projects
      summary: List all sources
      description: List the ingested knowledge sources for a project.
      parameters:
        - $ref: '#/components/parameters/ProjectId'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/SourceList'
        '401':
          $ref: '#/components/responses/Unauthorized'
  /query/v1/projects/{project_id}/activity:
    get:
      operationId: getActivity
      tags:
        - Analytics
      summary: Activity data
      description: Retrieve activity/usage analytics for a project.
      parameters:
        - $ref: '#/components/parameters/ProjectId'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                type: object
        '401':
          $ref: '#/components/responses/Unauthorized'
  /query/v1/projects/{project_id}/question-answers:
    get:
      operationId: listQuestionAnswers
      tags:
        - Analytics
      summary: List question answers
      description: List question/answer records for a project.
      parameters:
        - $ref: '#/components/parameters/ProjectId'
        - $ref: '#/components/parameters/PageSize'
        - $ref: '#/components/parameters/PageNumber'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                type: object
        '401':
          $ref: '#/components/responses/Unauthorized'
  /query/v1/projects/{project_id}/end-users:
    get:
      operationId: listEndUsers
      tags:
        - Analytics
      summary: List end users
      description: List end users that have interacted with the project.
      parameters:
        - $ref: '#/components/parameters/ProjectId'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                type: object
        '401':
          $ref: '#/components/responses/Unauthorized'
  /query/v1/projects/{project_id}/coverage-gaps/periods:
    get:
      operationId: listCoverageGapsPeriods
      tags:
        - Analytics
      summary: List coverage gaps periods
      description: List coverage-gap analysis periods for a project.
      parameters:
        - $ref: '#/components/parameters/ProjectId'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                type: object
        '401':
          $ref: '#/components/responses/Unauthorized'
  /query/v1/coverage-gaps/periods/{period_id}:
    get:
      operationId: getCoverageGapsPeriod
      tags:
        - Analytics
      summary: Retrieve coverage gaps period
      description: Retrieve a single coverage-gap period by id.
      parameters:
        - name: period_id
          in: path
          required: true
          schema:
            type: string
            format: uuid
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                type: object
        '401':
          $ref: '#/components/responses/Unauthorized'
  /query/v1/projects/{project_id}/top-questions/periods:
    get:
      operationId: listTopQuestionsPeriods
      tags:
        - Analytics
      summary: List top questions periods
      description: List top-question analysis periods for a project.
      parameters:
        - $ref: '#/components/parameters/ProjectId'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                type: object
        '401':
          $ref: '#/components/responses/Unauthorized'
  /query/v1/top-questions/periods/{period_id}:
    get:
      operationId: getTopQuestionsPeriod
      tags:
        - Analytics
      summary: Retrieve top questions period
      description: Retrieve a single top-question period by id.
      parameters:
        - name: period_id
          in: path
          required: true
          schema:
            type: string
            format: uuid
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                type: object
        '401':
          $ref: '#/components/responses/Unauthorized'
components:
  securitySchemes:
    ApiKeyAuth:
      type: apiKey
      in: header
      name: X-API-KEY
      description: kapa.ai project API key, created in the API Keys tab of the platform.
  parameters:
    ProjectId:
      name: project_id
      in: path
      required: true
      description: The kapa.ai project (instance) identifier.
      schema:
        type: string
        format: uuid
    ThreadId:
      name: thread_id
      in: path
      required: true
      description: The Thread identifier returned by a chat call.
      schema:
        type: string
        format: uuid
    PageSize:
      name: page_size
      in: query
      required: false
      schema:
        type: integer
        default: 20
    PageNumber:
      name: page_number
      in: query
      required: false
      schema:
        type: integer
        default: 1
  responses:
    Unauthorized:
      description: Missing or invalid X-API-KEY.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
  schemas:
    ChatRequest:
      type: object
      required:
        - query
      properties:
        query:
          type: string
          description: The user's question.
          example: How do I get started?
        integration_id:
          type: string
          description: >-
            Integration identifier used to attribute usage analytics; calls
            without it appear as the "Unknown" integration.
        user:
          $ref: '#/components/schemas/User'
    CustomChatRequest:
      allOf:
        - $ref: '#/components/schemas/ChatRequest'
        - type: object
          properties:
            context:
              type: string
              description: Caller-supplied context to ground the answer.
    ChatResponse:
      type: object
      properties:
        answer:
          type: string
          description: The generated answer to the query.
        thread_id:
          type: string
          format: uuid
          description: Identifier of the Thread; use it to ask follow-up questions.
        question_answer_id:
          type: string
          format: uuid
          description: Identifier of this question/answer; used when submitting feedback.
        is_uncertain:
          type: boolean
          description: True when kapa.ai is uncertain about the answer.
        relevant_sources:
          type: array
          description: Sources used to construct the answer.
          items:
            $ref: '#/components/schemas/RelevantSource'
    RelevantSource:
      type: object
      properties:
        source_url:
          type: string
          format: uri
        title:
          type: string
        content:
          type: string
    User:
      type: object
      properties:
        email:
          type: string
          format: email
          description: End-user email for per-user analytics tracking.
        unique_client_id:
          type: string
          description: Stable client identifier for the end user.
    FeedbackRequest:
      type: object
      required:
        - question_answer_id
        - reaction
      properties:
        question_answer_id:
          type: string
          format: uuid
        reaction:
          type: string
          enum:
            - upvote
            - downvote
          description: The reaction on the answer.
        comment:
          type: string
          description: Optional free-text feedback.
    FeedbackResponse:
      type: object
      properties:
        question_answer_id:
          type: string
          format: uuid
        reaction:
          type: string
    RetrievalRequest:
      type: object
      required:
        - query
      properties:
        query:
          type: string
          description: The retrieval query.
        num_results:
          type: integer
          description: Maximum number of chunks to return.
    RetrievalResponse:
      type: object
      properties:
        relevant_sources:
          type: array
          items:
            $ref: '#/components/schemas/RetrievedChunk'
    RetrievedChunk:
      type: object
      properties:
        content:
          type: string
        source_url:
          type: string
          format: uri
        title:
          type: string
        score:
          type: number
          format: float
          description: Relevance score in descending order.
    Thread:
      type: object
      properties:
        id:
          type: string
          format: uuid
        project_id:
          type: string
          format: uuid
        messages:
          type: array
          items:
            type: object
            properties:
              role:
                type: string
              content:
                type: string
        created_at:
          type: string
          format: date-time
    ThreadList:
      type: object
      properties:
        count:
          type: integer
        results:
          type: array
          items:
            $ref: '#/components/schemas/Thread'
    Project:
      type: object
      properties:
        id:
          type: string
          format: uuid
        name:
          type: string
    IntegrationList:
      type: object
      properties:
        results:
          type: array
          items:
            type: object
            properties:
              id:
                type: string
                format: uuid
              name:
                type: string
              type:
                type: string
    SourceList:
      type: object
      properties:
        results:
          type: array
          items:
            type: object
            properties:
              id:
                type: string
                format: uuid
              type:
                type: string
              url:
                type: string
                format: uri
    Error:
      type: object
      properties:
        detail:
          type: string