Streaming - Mirobody

Set stream: true on POST /v1/responses and the reply arrives as standard OpenAI Responses response.* SSE events — every frame is event: <type> + data: <json>, with a monotonic sequence_number. Official SDK stream loops consume it as-is.

from openai import OpenAI

client = OpenAI(api_key="mb_live_...", base_url="https://api.mirobody.ai/v1")

with client.responses.stream(
    model="mirobody-flash",
    input="How is my fasting glucose trending?",
    user="alice",
) as stream:
    for event in stream:
        if event.type == "response.output_text.delta":
            print(event.delta, end="", flush=True)

Event table

Event	Meaning
`response.created`	The run started — carries a response snapshot with `status: "in_progress"`.
`response.in_progress`	Follows immediately (OpenAI parity).
`response.output_item.added`	A new output item opened (`reasoning`, `message`, or `function_call`) — carries `output_index` + the in-progress item.
`response.reasoning_summary_part.added` / `.done`	A reasoning summary part opened / closed.
`response.reasoning_summary_text.delta` / `.done`	Provider-supplied reasoning-summary fragments, then the full summary.
`response.content_part.added` / `.done`	An answer content part opened / closed.
`response.output_text.delta` / `.done`	Answer text fragments, then the full text — the channel most clients render.
`response.function_call_arguments.delta` / `.done`	A client-tool handoff’s arguments (see Function calling).
`response.output_item.done`	The open item completed — carries the finished item.
`response.mirobody_tool_call`	Mirobody extension, side-channel — a built-in server tool was called. See below.
`response.mirobody_tool_result`	Mirobody extension, side-channel — a built-in server tool’s result landed. See below.
`response.completed`	Terminal: carries the full final response object (`output`, `usage`, `tool_steps`, `health_records`, `citations`).
`response.failed`	Terminal error: carries a response snapshot with `status: "failed"` and an `error` object.

Items stream strictly one at a time: reasoning first (when the tier emits it), then the message, then any function_call handoffs — output_index increments per item, and the indexes match the final output array on response.completed.

Server-tool side-channel

Built-in server tools (data search, literature, …) are not output items — official SDKs would mis-parse unknown item types, so their trace rides a dedicated event that standard stream loops safely ignore:

event: response.mirobody_tool_call
data: {"type":"response.mirobody_tool_call","sequence_number":7,
       "tool_step":{"id":"mtc_0","call_id":"call_1a2b...","name":"query_health_data",
                    "arguments":"{\"query\": \"fasting glucose last 90 days\"}"}}

It fires when the tool is called; it does not open an output item or advance output_index. Render it if you want an activity feed (“Searching your records…”); skip it and nothing breaks. response.mirobody_tool_result is its pair, pushed when that tool’s result lands — the other half of the side-channel, equally ignorable:

event: response.mirobody_tool_result
data: {"type":"response.mirobody_tool_result","sequence_number":9,
       "tool_step":{"id":"mtc_0","call_id":"call_1a2b...","name":"query_health_data",
                    "result":"...","truncated":false}}

Match a result to its call by id / call_id. The streamed result is truncated to 4096 characters (truncated: true when clipped); the full value is always on the final response object (response.completed) under tool_steps[].result.

Failure events

On an upstream error the stream ends with response.failed (not a broken pipe):

event: response.failed
data: {"type":"response.failed","sequence_number":12,
       "response":{"id":"resp_...","status":"failed",
                   "error":{"type":"upstream_error","message":"..."}}}

For the Answers API’s simpler chat.completion.chunk streaming, see Answers API → Streaming.

​Event table

​Server-tool side-channel

​Failure events

​See also

Event table

Server-tool side-channel

Failure events

See also