Chat completion SSE stream. The client opens this channel by issuing
`POST /chat/completions` with `Content-Type: application/json`,
`Accept: text/event-stream` (implied), and a JSON body containing
`stream: true`. The server responds with `Content-Type: text/event-stream`
and emits a sequence of `data:` lines, each carrying one JSON-serialized
`chat.completion.chunk` object, followed by a final `
Subscribe to streamed chat completion chunks (SSE).
Messages
ChatCompletionChunk
A single SSE `data:` event carrying one JSON `chat.completion.chunk`
object. Many of these are emitted per request, in order.
Content-Type: application/json
ChatCompletionUsageChunk
Optional chunk emitted only when the request body sets
`stream_options.include_usage: true`. Streamed immediately before
`data: [DONE]`.
Content-Type: application/json
StreamDone
The literal SSE event `data: [DONE]` that marks end of stream. Not
JSON; the payload is the string `[DONE]`.
Content-Type: text/plain
About AsyncAPI
The AsyncAPI specification describes event-driven APIs the way OpenAPI describes request/response APIs. A channel is the named pipe — a webhook URL, a Kafka topic, a WebSocket route, an MQTT subject — that producers and consumers publish or subscribe to. Each channel carries one or more messages with structured payloads, and an operation declares whether a given party sends or receives on that channel.
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