Claude Code v2.0.44

What: A new system that allows Claude to dynamically adjust how much reasoning it applies to tasks based on an experiment-controlled effort level.

How it works: This feature is controlled by the Statsig experiment flag tengu_effort_exp with parameter tengu_effort_level. When enabled, it accepts three levels:

• low (maps to effort value 45)
• medium (maps to effort value 75)
• high (maps to effort value 99)

Details:

• The feature automatically injects reasoning effort instructions into Claude's system prompt when the experiment is active
• Lower effort values prioritize faster, more efficient responses
• Higher effort values enable maximum reasoning and thoroughness
• The effort scale ranges from 0-100, with Claude instructed to vary reasoning depth accordingly
• This is an A/B test feature - only users enrolled in the Statsig experiment will have access
• Evidence: function sQI() at line 470523, aQI mapping at line 470940, system prompt integration at line 470717

Technical implementation:

• New function sQI() reads experiment configuration and generates reasoning effort instructions
• Mapping object aQI = { low: 45, medium: 75, high: 99 } converts string levels to numeric values
• The generated <reasoning_effort> XML tag is appended to the system prompt array
• Experiment values are retrieved via the Statsig client using the d3() helper function

What: Significant restructuring of module initialization and dependencies

Details:

• The module initialization variable was renamed from LQ to Pr
• Initialization dependencies were completely reorganized with different function calls
• Usage of the initialization function was reduced from 69 call sites to 6, suggesting more efficient lazy loading or granular initialization
• Import statements were reorganized by the bundler, but no functional changes to imports were made
• Evidence: variable Pr at line 470923 (previously LQ at line 480763 in v2.0.43)