GPT-5.6 Luna on Run BiOS

gpt-5.6-luna

+50%First top-up bonus

Top up $20 and we add 50%. That gives you about 50.0M input tokens extra on GPT-5.6 Luna, on us.

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266K contextVisionTool callingReasoningPrompt caching

Pricing

USD per 1M tokens

Input	$0.20
Output	$1.20
Cached input	$0.0290% below fresh input
Cache write (5m)	$0.25

Billed per token with no minimum and no monthly fee. Price your workload

Capabilities and limits

Context window: 266K tokens
Max output: 125K tokens
Modality: multimodal
Tool calling: Supported
Vision: Supported
Reasoning: Optional
Reasoning effort: low, medium, high, xhigh, max (default: medium)
Prompt caching: Supported (automatic)
Cache minimum: 1K tokens

Measured performance

Time to first token (p50): 3.0 s
Time to first token (p95): 6.0 s
Throughput (avg): 190.0 tok/s
Throughput (p50): 200.0 tok/s

Measured on real Run BiOS traffic over the trailing 7d. Your figures will vary with prompt shape and region.

Call it now: OpenAI-compatible

curl https://api.runbios.ai/v1/chat/completions \
  -H "Authorization: Bearer $BIOS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-5.6-luna",
    "messages": [{ "role": "user", "content": "Hello" }]
  }'

Existing OpenAI SDK code works by changing the base URL and the key. API overview

Model card

Curated by Run BiOS · benchmark figures, where present, are the card’s own, not our measurements

GPT-5.6 Luna is designed for cost-sensitive, high-volume workloads. It roughly corresponds to the nano model tier used in earlier GPT-5 families.

Model details

Property	Value
Developer	OpenAI
Model ID	`gpt-5.6-luna`
OpenAI default snapshot	`gpt-5.6-luna`
Input	Text, image
Output	Text
Context window	272,000 tokens on Run BiOS (OpenAI's full window is 1,050,000 tokens)
Max output tokens	128,000
Knowledge cutoff	Feb 16, 2026
Reasoning	Yes

Details above are from OpenAI's official model page; context window and input types are as served on Run BiOS.

On Run BiOS

Configurable reasoning. Reasoning levels low, medium, high, xhigh, max; the default is medium. Turn reasoning off with reasoning_effort: "none" (OpenAI API) or thinking: {"type": "disabled"} (Anthropic Messages API).
Reasoning summaries. When reasoning is on, OpenAI may return a summary of the model's reasoning: in reasoning_content on the OpenAI API, and in thinking blocks on the Anthropic Messages API when thinking.display is summarized. OpenAI does not return a summary for every request.
Tool calling. Function tools with tool_choice auto, required, a named function or none, including parallel tool calls, and together with reasoning.
Structured outputs. response_format with json_schema or json_object.
Image input. Text and image input, text output.
Sampling parameters. With reasoning off, temperature, top_p and seed are supported. With reasoning on, sampling parameters are not applied; the request is still served. stop is not supported by this model.
Prompt caching. Automatic for repeated prompt prefixes of at least 1,024 tokens. Cache reads bill at 0.1× the input rate and cache writes at 1.25×, as OpenAI charges.
Two APIs. Works with the OpenAI Chat Completions API (/v1/chat/completions) and the Anthropic Messages API (/v1/messages).

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