Streaming

Compose uses Server-Sent Events for streaming. Native routes can include Compose events alongside OpenAI-shaped chunks. External routes remove Compose events so OpenAI-compatible clients only see the stream shape they expect.

Chat streaming

curl -N https://api.compose.market/v1/chat/completions \
  -H "Authorization: Bearer $COMPOSE_MARKET_API_KEY" \
  -H "Content-Type: application/json" \
  -H "x-chain-id: 43113" \
  -d '{
    "model": "gpt-5.5",
    "stream": true,
    "stream_options": { "include_usage": true },
    "messages": [
      { "role": "user", "content": "Give me one line." }
    ]
  }'

Chat streams use OpenAI chat completion chunks:

data: {"id":"resp_...","object":"chat.completion.chunk","choices":[{"delta":{"role":"assistant","content":"Hello"}}]}

data: {"id":"resp_...","object":"chat.completion.chunk","choices":[{"delta":{},"finish_reason":"stop"}]}

data: [DONE]

When usage is available, Compose sends a final usage chunk before [DONE].

Responses streaming

POST /v1/responses streams Responses-style events. Use it when you want response IDs, input item retrieval, or previous_response_id history.

{
  "model": "gpt-5.5",
  "stream": true,
  "input": [
    { "role": "user", "content": "Summarize the deployment log." }
  ]
}

The API stores response records for retrieval through:

Method	Path
`GET`	`/v1/responses/{id}`
`GET`	`/v1/responses/{id}/input_items`
`POST`	`/v1/responses/{id}/cancel`

Compose events on native routes

Native streams can include named events:

Event	Meaning
`compose.receipt`	Payment settled. Contains final amount, network, line items, and optional transaction hash.
`compose.error`	Structured stream error before the stream closes.
`compose.video.status`	Video job status update.

External streams remove these events and keep the stream OpenAI-shaped.

Video status streaming

GET /v1/videos/{id}/stream

The endpoint polls the provider job and sends compose.video.status until the job is completed or failed. Optional query parameters:

Parameter	Default	Bounds
`pollIntervalMs`	`2000`	`500` to `30000`
`timeoutMs`	`600000`	`5000` to `3600000`

Overview

External Use

Families

Modalities

Guides

Chat streaming

Responses streaming

Compose events on native routes

Video status streaming

​Chat streaming

​Responses streaming

​Compose events on native routes

​Video status streaming

​Related

Chat streaming

Responses streaming

Compose events on native routes

Video status streaming

Related