Microsoft Copilot Chat API

openapi: 3.1.0
info:
  title: Microsoft Copilot Microsoft 365 Copilot APIs Change Notifications Chat API
  description: REST APIs under the Microsoft Graph /copilot/ namespace that enable secure access to Microsoft 365 Copilot capabilities including retrieval, search, chat, interaction export, and change notifications. These APIs provide production-ready AI capabilities that work directly with Microsoft 365 data while respecting existing permissions, sensitivity labels, compliance controls, and policy enforcement.
  version: 1.0.0
  contact:
    name: Microsoft Graph Support
    url: https://learn.microsoft.com/en-us/graph/overview
  license:
    name: Microsoft API Terms of Use
    url: https://learn.microsoft.com/en-us/legal/microsoft-apis/terms-of-use
  termsOfService: https://learn.microsoft.com/en-us/legal/m365-copilot-apis/terms-of-use
servers:
- url: https://graph.microsoft.com/v1.0
  description: Microsoft Graph v1.0 (production)
- url: https://graph.microsoft.com/beta
  description: Microsoft Graph beta (preview)
security:
- oauth2: []
tags:
- name: Chat
  description: Programmatically start and continue conversations with Microsoft 365 Copilot using enterprise search and web search grounding. Preview API.
  externalDocs:
    url: https://learn.microsoft.com/en-us/microsoft-365-copilot/extensibility/api/ai-services/chat/overview
paths:
  /copilot/chat/conversations:
    post:
      operationId: copilot.chat.startConversation
      summary: Microsoft Copilot Start a Chat Conversation
      description: Start a new multi-turn conversation with Microsoft 365 Copilot. The Chat API allows you to programmatically engage in conversations using enterprise search grounding and web search grounding. Responses are grounded in Microsoft 365 data and web content while respecting all existing permissions and compliance controls. This API is currently in preview.
      tags:
      - Chat
      externalDocs:
        url: https://learn.microsoft.com/en-us/microsoft-365-copilot/extensibility/api/ai-services/chat/overview
      security:
      - oauth2:
        - Chat.Read
      parameters:
      - $ref: '#/components/parameters/authorizationHeader'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/ChatConversationRequest'
            examples:
              startConversation:
                summary: Start a new conversation
                value:
                  prompt: What are the key highlights from last quarter's financial report?
              conversationWithOptions:
                summary: Start conversation with web search disabled
                value:
                  prompt: Summarize the latest HR policy changes
                  enableWebSearch: false
      responses:
        '200':
          description: Conversation started and response returned successfully.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ChatConversationResponse'
              examples:
                CopilotChatStartconversation200Example:
                  summary: Default copilot.chat.startConversation 200 response
                  x-microcks-default: true
                  value:
                    conversationId: '500123'
                    message:
                      id: abc123
                      body:
                        contentType: example_value
                        content: example_value
                      citations:
                      - {}
                      createdDateTime: '2026-01-15T10:30:00Z'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/Forbidden'
        '429':
          $ref: '#/components/responses/TooManyRequests'
      x-microcks-operation:
        delay: 0
        dispatcher: FALLBACK
  /copilot/chat/conversations/{conversationId}/messages:
    post:
      operationId: copilot.chat.continueConversation
      summary: Microsoft Copilot Continue a Chat Conversation
      description: Send a follow-up message in an existing multi-turn conversation with Microsoft 365 Copilot. Uses the conversation context from prior turns to provide more relevant and contextual responses.
      tags:
      - Chat
      security:
      - oauth2:
        - Chat.Read
      parameters:
      - $ref: '#/components/parameters/authorizationHeader'
      - name: conversationId
        in: path
        required: true
        description: The unique identifier of the conversation to continue.
        schema:
          type: string
        example: '500123'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/ChatMessageRequest'
            examples:
              followUp:
                summary: Send a follow-up message
                value:
                  prompt: Can you provide more details on the revenue figures?
      responses:
        '200':
          description: Message sent and response returned successfully.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ChatMessageResponse'
              examples:
                CopilotChatContinueconversation200Example:
                  summary: Default copilot.chat.continueConversation 200 response
                  x-microcks-default: true
                  value:
                    message:
                      id: abc123
                      body:
                        contentType: example_value
                        content: example_value
                      citations:
                      - {}
                      createdDateTime: '2026-01-15T10:30:00Z'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/Forbidden'
        '429':
          $ref: '#/components/responses/TooManyRequests'
      x-microcks-operation:
        delay: 0
        dispatcher: FALLBACK
components:
  responses:
    Forbidden:
      description: Forbidden. The caller does not have the required permissions or the user does not have a Microsoft 365 Copilot license.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ODataError'
    Unauthorized:
      description: Unauthorized. A valid bearer token is required.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ODataError'
    BadRequest:
      description: Bad request. The request body or parameters are invalid.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ODataError'
    TooManyRequests:
      description: Too many requests. The Retrieval API supports up to 200 requests per user per hour.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ODataError'
  schemas:
    ChatMessageRequest:
      type: object
      required:
      - prompt
      properties:
        prompt:
          type: string
          description: Natural language prompt to continue the conversation.
          example: example_value
        enableWebSearch:
          type: boolean
          default: true
          description: Whether to enable web search grounding for this message.
          example: true
    ChatMessage:
      type: object
      properties:
        id:
          type: string
          description: The unique identifier for the message.
          example: abc123
        body:
          type: object
          properties:
            contentType:
              type: string
              description: The content type of the body (e.g., text, html).
            content:
              type: string
              description: The text content of the Copilot response.
          example: example_value
        citations:
          type: array
          description: Sources referenced in the Copilot response.
          items:
            type: object
            properties:
              title:
                type: string
                description: The title of the cited source.
              url:
                type: string
                format: uri
                description: The URL of the cited source.
              snippet:
                type: string
                description: A relevant snippet from the cited source.
          example: []
        createdDateTime:
          type: string
          format: date-time
          description: The timestamp when the message was created.
          example: '2026-01-15T10:30:00Z'
    ODataError:
      type: object
      properties:
        error:
          type: object
          properties:
            code:
              type: string
              description: The error code.
            message:
              type: string
              description: The error message.
            innerError:
              type: object
              properties:
                date:
                  type: string
                  format: date-time
                request-id:
                  type: string
                client-request-id:
                  type: string
          example: example_value
    ChatConversationResponse:
      type: object
      properties:
        conversationId:
          type: string
          description: The unique identifier for the conversation for multi-turn use.
          example: '500123'
        message:
          $ref: '#/components/schemas/ChatMessage'
    ChatMessageResponse:
      type: object
      properties:
        message:
          $ref: '#/components/schemas/ChatMessage'
    ChatConversationRequest:
      type: object
      required:
      - prompt
      properties:
        prompt:
          type: string
          description: Natural language prompt to send to Microsoft 365 Copilot to start a conversation.
          example: example_value
        enableWebSearch:
          type: boolean
          default: true
          description: Whether to enable web search grounding for this message. Defaults to true. Must be toggled off per message if not desired.
          example: true
        fileReferences:
          type: array
          description: Optional OneDrive and SharePoint file references to provide as additional context.
          items:
            type: object
            properties:
              url:
                type: string
                format: uri
                description: The URL of the file to reference.
          example: []
  parameters:
    authorizationHeader:
      name: Authorization
      in: header
      required: true
      description: 'Bearer token obtained via OAuth 2.0. Format: Bearer {token}'
      schema:
        type: string
        pattern: ^Bearer\s.+$
  securitySchemes:
    oauth2:
      type: oauth2
      description: OAuth 2.0 authorization using Microsoft identity platform (Azure AD). Requires a Microsoft 365 Copilot license for each user accessing Copilot API functionality.
      flows:
        authorizationCode:
          authorizationUrl: https://login.microsoftonline.com/common/oauth2/v2.0/authorize
          tokenUrl: https://login.microsoftonline.com/common/oauth2/v2.0/token
          scopes:
            Files.Read.All: Read all files the user can access
            Sites.Read.All: Read items in all site collections
            ExternalItem.Read.All: Read external items from Copilot connectors
            Chat.Read: Read user chat messages
            AIInteraction.Read.All: Read all AI interactions for compliance
externalDocs:
  description: Microsoft 365 Copilot APIs Overview
  url: https://learn.microsoft.com/en-us/microsoft-365-copilot/extensibility/copilot-apis-overview