LeanCTX — Context Gateway for AI Systems. Control what your AI can see. Open-source Engine for context selection, supported controls, and evidence.
LeanCTX is a local Rust program that controls the repository context an AI coding agent receives, including selecting, compressing, remembering, and tracking information. Developers use it alongside coding agents to reduce repeated context and manage what those agents read and execute, while the catalogue entries provide related rules, skills, and instructions.
This repository also configures its own agents. See what lean-ctx tells them →
Skill Claude CodeCodex
Pick the right lean-ctx tool for reading, searching, understanding and running code with fewer tokens and fewer round trips. Use when lean-ctx MCP tools (ctx) are available or when a command output, file read or search would be large.
Skill Claude CodeCodex
Pick the right lean-ctx tool for reading, searching, understanding and running code with fewer tokens and fewer round trips. Use when lean-ctx MCP tools (ctx) are available or when a command output, file read or search would be large.
Skill Claude CodeCodex
Review how the lean-ctx ctx MCP tools performed in the current session and file upstream issues for confirmed problems. Use when the user asks to review/audit lean-ctx tool performance, says "lean-ctx review", asks why ctx tools failed or fell back to native tools, or wants to report a lean-ctx bug.