GPT-6 Astra Pro

POST/v1/responses

GPT-6 Astra Pro is the same GPT-6 Astra model, OpenAI's most capable GPT-6 tier, served in OpenAI's pro reasoning mode rather than as different weights. In pro mode the model does more work on each request before returning one final answer, which OpenAI suggests for complex optimization, high-value coding or review, and deep analysis. Expect higher latency and token usage than standard Astra, so reserve it for problems where a marginal quality gain changes the outcome.

Request body

Parameters supported by the OpenAI Responses API. Values, defaults, and limits are read from the model registry.

stringmodelrequired

Model identifier. Set to openai/gpt-6-astra-pro.

Default: openai/gpt-6-astra-pro

string | array<object>inputrequired

Input text or structured content for the response.

Optional<integer>max_tokens

Maximum number of tokens the model may generate in the response.

Maximum: 128000

Optional<boolean>stream

When true, returns incremental Server-Sent Events instead of one completed response.

Default: false

Optional<array>tools

Tool definitions that the model may call during the response.

Optional<string>tool_choice

Controls whether the model may call a tool and, when supported, which tool it must call.

Optional<object>response_format

Controls the response format, including JSON mode or structured JSON output when supported.

Optional<integer>seed

Seed used to make sampling more reproducible when the provider supports it.

Optional<integer>max_completion_tokens

Request parameter supported by this model.

Maximum: 128000

Optional<string>reasoning_effort

Request parameter supported by this model.

Allowed values: low, medium, high, xhigh, max

Default: medium

Response Schema

Fields returned by the OpenAI Responses API.

stringidrequired

Unique response identifier.

stringmodelrequired

Model that generated the response.

stringobjectrequired

Response object type.

array<object>outputrequired

Generated response output items.

stringstatusrequired

Response lifecycle status.

Optional<object>usage

Token usage when available.

Model capabilities

array<string>capability_tagsrequired

Capabilities declared by the model registry.

Default: chat, vision, reasoning, structured_output, function_calling

integercontext_lengthrequired

Maximum context window accepted by this model.

Default: 1050000 tokens

stringexecution_moderequired

Execution mode declared by the model registry.

Default: sync

curl -X POST https://api.sandbase.ai/v1/responses \
  -H "Authorization: Bearer $SANDBASE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "openai/gpt-6-astra-pro",
  "input": "Describe this product in one sentence."
}'

Response200 OK

{
  "id": "resp_abc123",
  "object": "response",
  "status": "completed",
  "model": "openai/gpt-6-astra-pro",
  "output": [
    {
      "type": "message",
      "content": [
        {
          "type": "output_text",
          "text": "A concise product description."
        }
      ]
    }
  ]
}