Vapi File-Backed Knowledge Base Assistant

arazzo: 1.0.1
info:
  title: Vapi File-Backed Knowledge Base Assistant
  summary: Upload a file, build a query tool knowledge base from it, and create an assistant that uses it.
  description: >-
    The retrieval-augmented assistant flow. It uploads a document to Vapi,
    creates a query tool whose Google knowledge base is backed by that file, and
    then creates a voice AI assistant that references the tool so it can answer
    from the uploaded content. Every step spells out its request inline so the
    flow can be read and executed without opening the underlying OpenAPI
    description.
  version: 1.0.0
sourceDescriptions:
- name: filesApi
  url: ../openapi/vapi-files-api-openapi.yml
  type: openapi
- name: toolsApi
  url: ../openapi/vapi-tools-api-openapi.yml
  type: openapi
- name: assistantsApi
  url: ../openapi/vapi-assistants-api-openapi.yml
  type: openapi
workflows:
- workflowId: file-knowledge-base-assistant
  summary: Upload a file, wrap it in a query tool, and back an assistant with it.
  description: >-
    Uploads a document, creates a query tool with a Google knowledge base over
    the uploaded file, then creates an assistant that references the tool by id.
  inputs:
    type: object
    required:
    - apiToken
    - fileContent
    - name
    - firstMessage
    - systemPrompt
    properties:
      apiToken:
        type: string
        description: Vapi private API key used as a Bearer token.
      fileContent:
        type: string
        description: The file payload to upload to Vapi.
      knowledgeBaseName:
        type: string
        description: A name for the knowledge base built from the file.
        default: Uploaded Knowledge Base
      knowledgeBaseDescription:
        type: string
        description: A description of what the knowledge base contains.
        default: Knowledge base built from an uploaded document.
      name:
        type: string
        description: A human-readable name for the assistant.
      firstMessage:
        type: string
        description: The opening message the assistant speaks.
      systemPrompt:
        type: string
        description: The system prompt that shapes the assistant's behavior.
  steps:
  - stepId: uploadFile
    description: Upload the document to Vapi so it can back a knowledge base.
    operationId: FileController_create
    parameters:
    - name: Authorization
      in: header
      value: Bearer $inputs.apiToken
    requestBody:
      contentType: multipart/form-data
      payload:
        file: $inputs.fileContent
    successCriteria:
    - condition: $statusCode == 201
    outputs:
      fileId: $response.body#/id
  - stepId: createQueryTool
    description: >-
      Create a query tool whose Google knowledge base is backed by the uploaded
      file so an assistant can retrieve from it.
    operationId: ToolController_create
    parameters:
    - name: Authorization
      in: header
      value: Bearer $inputs.apiToken
    requestBody:
      contentType: application/json
      payload:
        type: query
        knowledgeBases:
        - name: $inputs.knowledgeBaseName
          provider: google
          description: $inputs.knowledgeBaseDescription
          fileIds:
          - $steps.uploadFile.outputs.fileId
    successCriteria:
    - condition: $statusCode == 201
    outputs:
      toolId: $response.body#/id
  - stepId: createAssistant
    description: >-
      Create the assistant and attach the query tool by id so it can answer from
      the uploaded knowledge base.
    operationId: AssistantController_create
    parameters:
    - name: Authorization
      in: header
      value: Bearer $inputs.apiToken
    requestBody:
      contentType: application/json
      payload:
        name: $inputs.name
        firstMessage: $inputs.firstMessage
        model:
          provider: openai
          model: gpt-5.4
          messages:
          - role: system
            content: $inputs.systemPrompt
          toolIds:
          - $steps.createQueryTool.outputs.toolId
        voice:
          provider: azure
          voiceId: andrew
    successCriteria:
    - condition: $statusCode == 201
    outputs:
      assistantId: $response.body#/id
  outputs:
    fileId: $steps.uploadFile.outputs.fileId
    toolId: $steps.createQueryTool.outputs.toolId
    assistantId: $steps.createAssistant.outputs.assistantId