Opus 4.7 Can Follow ~500 Instructions, Up from ~150 a Year Ago

Research from July 2025 found that LLMs could follow ~150 instructions before failing to adhere to extras. An update in May 2026 shows Opus 4.7 now reliably follows ~500 instructions, while GPT-5.5 handles ~5000. The findings suggest developers can fit more directives into CLAUDE.md files without causing instruction dropout.

Key numbers

• July 2025: ~150 instructions reliably executable by top models.
• May 2026: Opus 4.7 reliably follows ~500 instructions, GPT-5.5 ~5000.

This improvement isn't linear—it's roughly an order of magnitude over the year. The practical impact: longer, more detailed CLAUDE.md files are now feasible, with less risk of the model ignoring later rules.

What changed

The original July 2025 research capped usable instructions at ~150. The new data (May 2026) indicates Opus 4.7 can handle ~500 without degradation. GPT-5.5's ~5000 capacity suggests even larger prompt structures can be maintained.

For developers using AI coding agents, this means you can expand your instruction files—include more edge cases, style preferences, or project-specific constraints—without the model losing track.