Capn-Hook

TLDR Dev · 6 hours ago

Capn-Hook is a persistent memory system for coding agents that saves discovered file locations and codebase structure between sessions, reducing token usage by 77% on repeated questions across 60 real developer queries on five production codebases. The tool uses file fingerprinting to automatically invalidate saved answers when underlying files change, integrating with Claude Code and Codex through session hooks that let agents ask before searching and chart answers after discovery. This reduces repeated exploration costs from minutes to seconds while maintaining correctness across all test cases.