Responses API

POST /v1/responses accepts Responses-style input and returns Responses objects or canonical Responses SSE events. It uses KosCompute-hosted models and shares the router's admission, accounting, and Zero Data Retention behavior.

curl https://api.koscompute.com/v1/responses \
  -H "Authorization: Bearer $KOSCOMPUTE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "qwen/qwen3.8-27b",
    "input": "Explain idempotency keys in two bullets.",
    "max_output_tokens": 220
  }'

Input¶

input may be a string or an array of typed items. Supported items include message text, function_call, and function_call_output. Message content accepts strings or typed input_text and output_text parts. Media content is not enabled on this endpoint; use Chat Completions for vision.

Stateless behavior¶

KosCompute does not retain Responses. store:true and a non-null previous_response_id return 400 unsupported_parameter. Resend the conversation state required for the next turn. prompt_cache_key, hosted conversations, background mode, and hosted OpenAI tools are not advertised.

Tools and structured text¶

Only local function tools are supported. Tool names and JSON Schemas are validated. tool_choice accepts none, auto, required, or a named function. A returned function call has a call_id; send a later function_call_output with that same ID.

Use text.format.type:"json_object" or json_schema on a model that advertises the matching feature. Hosted search, file, computer, image, and other provider tools are rejected rather than silently ignored.

Reasoning¶

Use the reasoning object with supported fields such as effort, max_tokens, enabled, and exclude. Public reasoning text and summaries are not exposed; usage can include a reasoning-token count. The total max_output_tokens budget still includes reasoning.

Streaming lifecycle¶

With stream:true, the normal lifecycle begins with response.created and response.in_progress, followed by output item/content delta events, and ends with response.completed. Tool arguments use function-call delta events. A failure after headers have been sent appears as a terminal stream error rather than a replacement HTTP status.