GPT-5.6 Luna with Pro reasoning mode. Pro mode performs more model work for difficult tasks; reasoning effort remains independently configurable and defaults to medium.
Added Jul 9, 2026
Context Window
1.1M
Max Output
128K
Input Price (Auto)
$0.20/1M
Output Price (Auto)
$1.20/1M
Cache Read (Auto)
$0.020/1M
Capabilities
Benchmarks
Benchmarks
Performance metrics and benchmarks
Sourced from Artificial Analysis.
Intelligence Index
37.3
Coding Index
71.4
Agentic work
AutomationBench-AA
Workflow automation with guardrail penalties
50.2%
Better than 69% of models compared
AutomationBench-AA Tasks Completed
Fully completed workflows without guardrail violations
18.6%
Better than 28% of models compared
Harvey LAB-AA
Legal agentic work criterion pass rate
87.9%
Better than 56% of models compared
AA-Briefcase
Agentic knowledge work (Elo)
1342 Elo
Better than 77% of models compared
GDPval-AA v2
Economically valuable tasks (Elo)
1443 Elo
Better than 83% of models compared
Document reasoning
GDP.pdf
Professional PDF reasoning: all-pass rate
24.0%
Better than 85% of models compared
AA-LCR v1.1
Long context reasoning with updated grading
83.7%
Better than 97% of models compared
MLCR-AA
Medical long-context reasoning
19.4%
Better than 67% of models compared
Reasoning
HLE
Humanity's Last Exam
39.5%
Better than 89% of models compared
Coding
Terminal-Bench v4.0
Practical coding and terminal tasks
11.6%
Better than 67% of models compared
SciCode
Python programming for scientific computing
53.6%
Better than 70% of models compared
Legacy benchmarks
GPQA Diamond (legacy)
Graduate-level scientific reasoning
91.1%
Better than 91% of models compared
AA-LCR (unversioned / legacy)
Long context reasoning evaluation
83.7%
Better than 97% of models compared
Last updated Sep 28, 2026
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