In 1 in 6 repos with both files, Claude Code never loads the AGENTS.md (gethrbr.com)

On October 18, 2026, Harbor published findings on the interactions between CLAUDE.md and AGENTS.md files in public GitHub repositories, analyzing 3,905 of each file type. Among the key takeaways, they discovered that in about 16% of repos containing both files, CLAUDE.md did not reference AGENTS.md, leading to a situation where Claude Code often ignores the AGENTS.md altogether. Additionally, 15% of the CLAUDE.md files contained only text instructing Claude to read AGENTS.md, which is ineffective unless Claude decides to open it. These findings indicate potential gaps in the intended functionality and interactions between these context files, suggesting developers may not be fully leveraging Claude's capabilities. This analysis is significant for the AI/ML community as it highlights the operational limitations and design considerations that developers face when integrating AI models like Claude and Codex. The study reveals that a considerable number of AGENTS.md files exceed the size limit for Codex, further complicating the effective utilization of these agents. By addressing these issues, such as ensuring proper references and managing file sizes, developers can enhance the performance and reliability of AI-driven applications.