glhf Chat Completions Streaming (HTTP + SSE)

asyncapi: '2.6.0'
id: 'urn:chat:glhf:openai:v1:chat-completions:sse'
info:
  title: glhf Chat Completions Streaming (HTTP + SSE)
  version: '1.0.0'
  description: |
    AsyncAPI 2.6 description of glhf's (glhf.chat) **chat completion streaming**
    surface.

    glhf does not publish a WebSocket API. Its OpenAI-compatible REST API exposes
    chat completions at `POST /chat/completions` under the base URL
    `https://glhf.chat/api/openai/v1`. The only asynchronous / event-style
    transport is **HTTP Server-Sent Events (SSE)**, delivered over that same REST
    endpoint when the request body sets `stream: true`. SSE is a one-way,
    server-to-client HTTP streaming channel; it is **not** WebSocket.

    Following the OpenAI streaming convention that glhf is compatible with,
    tokens are sent as data-only server-sent events as they become available,
    with the stream terminated by a `data: [DONE]` message.

    This AsyncAPI document models only the streamed events emitted by glhf's SSE
    response. The request body itself (model as hf:org/model, messages, etc.) is
    modeled in the companion OpenAPI document at `openapi/glhf-chat-openapi.yml`.
  contact:
    name: API Evangelist
    email: kin@apievangelist.com
    url: https://apievangelist.com
  license:
    name: API documentation - glhf
    url: https://glhf.chat
  x-transport-notes:
    transport: HTTP Server-Sent Events (SSE)
    protocol: https
    direction: server-to-client (one-way)
    mediaType: text/event-stream
    triggeredBy: 'POST https://glhf.chat/api/openai/v1/chat/completions with request body { "stream": true }'
    terminator: 'data: [DONE]'
    notWebSocket: true
    source: https://glhf.chat/users/settings/api
defaultContentType: text/event-stream
servers:
  glhf:
    url: glhf.chat/api/openai/v1
    protocol: https
    description: |
      glhf's OpenAI-compatible REST base. Chat completion streaming is delivered
      as HTTP Server-Sent Events over this base when `stream: true` is set on the
      JSON request body. AsyncAPI 2.6 does not define a dedicated SSE protocol
      identifier; `https` is used here and the SSE transport is documented in
      `info.x-transport-notes` and on each channel.
    security:
      - bearerAuth: []
channels:
  /chat/completions:
    description: |
      Chat completion SSE stream. The client opens this channel by issuing
      `POST /chat/completions` with `stream: true`. The server then emits
      `chat.completion.chunk` events as text/event-stream until a final
      `data: [DONE]` event terminates the stream.
    subscribe:
      operationId: receiveChatCompletionChunk
      summary: Receive streamed chat completion chunks as Server-Sent Events.
      bindings:
        http:
          type: response
          statusCode: 200
          headers:
            type: object
            properties:
              Content-Type:
                type: string
                const: text/event-stream
      message:
        $ref: '#/components/messages/ChatCompletionChunk'
components:
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      description: glhf API key passed as a Bearer token, created at https://glhf.chat/users/settings/api.
  messages:
    ChatCompletionChunk:
      name: ChatCompletionChunk
      title: Chat Completion Chunk
      contentType: text/event-stream
      summary: A single data-only Server-Sent Event carrying a chat completion delta.
      payload:
        type: object
        properties:
          id:
            type: string
          object:
            type: string
            const: chat.completion.chunk
          created:
            type: integer
          model:
            type: string
          choices:
            type: array
            items:
              type: object
              properties:
                index:
                  type: integer
                delta:
                  type: object
                  properties:
                    role:
                      type: string
                    content:
                      type: string
                finish_reason:
                  type: string
                  nullable: true