> ## Documentation Index
> Fetch the complete documentation index at: https://docs.case.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Chat completions

> Create a completion for the provided prompt and parameters. Compatible with OpenAI's chat completions API. Supports 40+ models including GPT-4, Claude, Gemini, and CaseMark legal AI models. Includes streaming support, token counting, and usage tracking.



## OpenAPI

````yaml /openapi.json post /llm/v1/chat/completions
openapi: 3.1.0
info:
  title: Case.dev API
  description: >-
    The AI-native platform for legal technology. Build smarter legal
    applications with our suite of AI-powered APIs.
  version: 1.0.0
  contact:
    name: Case.dev Support
    email: support@casemark.com
    url: https://case.dev
  license:
    name: Proprietary
    url: https://case.dev/terms
servers:
  - url: https://api.case.dev
    description: Production
security:
  - bearerAuth: []
tags:
  - name: Vaults
    description: Secure document storage with semantic search and GraphRAG
  - name: Memory
    description: >-
      Persistent memory for AI agents with semantic search and 12 generic
      indexed tag fields
  - name: OCR
    description: Extract text from PDFs, images, and scanned documents
  - name: Voice
    description: Audio transcription and text-to-speech
  - name: LLMs
    description: Access 40+ language models through a unified API
  - name: Search
    description: Web search, AI answers, and deep research
  - name: Mail
    description: Managed inboxes for agent email workflows
  - name: Media
    description: Transcript retrieval and captioned media clip generation
  - name: Legal
    description: Legal research tools including citation verification
  - name: Privilege
    description: Privilege detection for e-discovery and litigation workflows
  - name: Compute
    description: Serverless GPU and CPU infrastructure
  - name: Format
    description: Document formatting and template rendering (MD/JSON to PDF/DOCX)
  - name: SuperDoc
    description: Document conversion and template automation
  - name: Webhooks
    description: Webhook endpoint management
  - name: System
    description: Public system metadata and discovery endpoints
  - name: Usage
    description: Usage reporting and webhook subscriptions
  - name: Database
    description: Serverless PostgreSQL databases with instant branching
  - name: Translation
    description: Language detection and translation for multilingual legal workflows
  - name: Skills
    description: Search and read legal AI skills for agents
  - name: Agents
    description: >-
      Create, manage, and execute AI agents with tool access, sandbox
      environments, and async run workflows
  - name: Matters
    description: Matter-native legal workspaces and orchestration primitives
  - name: Applications Projects
    description: Web application project management
  - name: Applications Deployments
    description: Web application deployment management
  - name: Applications Domains
    description: Custom domain configuration for applications
  - name: Applications Env Vars
    description: Environment variable management for applications
paths:
  /llm/v1/chat/completions:
    post:
      tags:
        - LLMs
      summary: Chat completions
      description: >-
        Create a completion for the provided prompt and parameters. Compatible
        with OpenAI's chat completions API. Supports 40+ models including GPT-4,
        Claude, Gemini, and CaseMark legal AI models. Includes streaming
        support, token counting, and usage tracking.
      operationId: createChatCompletion
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
                - messages
              properties:
                model:
                  type: string
                  description: >-
                    Model to use for completion. Defaults to casemark/core-large
                    if not specified
                  example: casemark/core-large
                messages:
                  type: array
                  description: List of messages comprising the conversation
                  items:
                    type: object
                    properties:
                      role:
                        type: string
                        enum:
                          - system
                          - user
                          - assistant
                        description: The role of the message author
                      content:
                        type: string
                        description: The contents of the message
                max_tokens:
                  type: integer
                  description: Maximum number of tokens to generate
                  example: 1000
                temperature:
                  type: number
                  description: Sampling temperature between 0 and 2
                  example: 0.7
                stream:
                  type: boolean
                  description: Whether to stream back partial progress
                  example: false
                casemark_show_reasoning:
                  type: boolean
                  description: >-
                    CaseMark-only: when true, allows reasoning fields in
                    responses. Defaults to false (reasoning is suppressed).
                  example: false
                top_p:
                  type: number
                  description: Nucleus sampling parameter
                frequency_penalty:
                  type: number
                  description: Frequency penalty parameter
                presence_penalty:
                  type: number
                  description: Presence penalty parameter
      responses:
        '200':
          description: Successful completion response
          content:
            application/json:
              schema:
                type: object
                properties:
                  id:
                    type: string
                    description: Unique identifier for the completion
                  object:
                    type: string
                    example: chat.completion
                  created:
                    type: integer
                    description: Unix timestamp of completion creation
                  model:
                    type: string
                    description: Model used for completion
                  choices:
                    type: array
                    items:
                      type: object
                      properties:
                        index:
                          type: integer
                        message:
                          type: object
                          properties:
                            role:
                              type: string
                            content:
                              type: string
                        finish_reason:
                          type: string
                  usage:
                    type: object
                    properties:
                      prompt_tokens:
                        type: integer
                      completion_tokens:
                        type: integer
                      total_tokens:
                        type: integer
                      cost:
                        type: number
                        description: Cost in USD
        '400':
          description: Invalid request parameters
        '401':
          description: Invalid or missing API key
        '403':
          description: API key does not have access to LLM service
components:
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      bearerFormat: API Key
      description: API key starting with `sk_case_`

````