Claude Code Removes 80% of Prompts, Opus 5 Increases Character Count by 72%

The Claude Code team has removed over 80% of the system prompts without a decline in programming performance. System prompts are the rules and environmental descriptions provided before each model call. Engineer Chen Cheng discovered that the simplification of prompts occurred in Opus 4.8, not in Opus 5. The prompts in Opus 4.7 were approximately 15,225 characters, reduced to 4,467 in 4.8, and increased to 7,694 in Opus 5, marking a 72% increase from 4.8. Claude Code indeed compressed the behavioral rules from 12,443 characters to 2,308, a reduction of about 81%. The previous details were replaced by a single statement: "Refer to existing code style." After the launch of Opus 5, Claude Code added two exclusive rules, primarily constraining its error interpretation and progress reporting. Despite the removal of many general rules, specific rules will still be supplemented when issues arise with the new model.

This content is provided for general informational purposes only and doesn't constitute financial, investment, legal, or tax advice. Any events, rewards, online promotions, or related information mentioned herein should not be considered a recommendation, solicitation, or invitation to purchase, sell, trade, or otherwise deal in any crypto assets. Crypto assets are highly volatile and may result in loss. The availability of WEEX services, products, and related events may vary by region. You are responsible for ensuring that your participation is in accordance with applicable local laws and regulations.