OpenAI model
GPT-5.6 Luna
Model ID: gpt-5.6-luna
GPT-5.6 Luna is a OpenAI model tracked in SteelEngine. It supports a 1.05M token context window. Pricing starts at $0.2/1M input tokens and $1.2/1M output tokens. Key capabilities include Tool choice, Structured outputs, Reasoning none, low, medium, high, xhigh, max. Best for reasoning-heavy tasks that need more deliberate model control.
Input price
$0.2/1M
Cached input
$0.02/1M
Output price
$1.2/1M
Context window
1.05M
Pricing and limits
Pricing below is generated directly from the provider registry in SteelEngine. All amounts are listed per one million tokens.
Input price
$0.2/1M
Cached input
$0.02/1M
Output price
$1.2/1M
Updated
Oct 19, 2026
Context window
1.05M tokens
Max output
128k tokens
Provider
OpenAI
Best for
Best for reasoning-heavy tasks that need more deliberate model control.
Capabilities
These capability flags are generated from the provider and model definitions tracked in SteelEngine.
Temperature
Not configurable
Reasoning effort
none, low, medium, high, xhigh, max
Verbosity
low, medium, high
Thinking levels
Not supported
Structured outputs
Supported (native)
Tool choice
Supported
Computer use
Not supported
Deep research
Not supported
Memory support
Supported
Max output tokens
128k
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Frequently asked questions
GPT-5.6 Luna is a OpenAI model available in SteelEngine. GPT-5.6 Luna is a OpenAI model tracked in SteelEngine. It supports a 1.05M token context window. Pricing starts at $0.2/1M input tokens and $1.2/1M output tokens. Key capabilities include Tool choice, Structured outputs, Reasoning none, low, medium, high, xhigh, max.