Show HN: Context Lens: View your CLI's agent context in realtime (github.com)

Context Lens has been introduced as a powerful local proxy tool that allows developers to gain real-time insights into their coding sessions with AI language models. By capturing API calls from various coding tools—including Claude Code, Codex, and Gemini CLI—Context Lens provides a detailed breakdown of context composition, revealing the proportions of system prompts, conversation history, and more. This transparency helps developers answer the crucial question of why their AI sessions may incur high costs, offering per-turn and per-session cost estimates that optimize resource usage. This tool is significant for the AI/ML community as it enables developers to analyze and understand the resource consumption of closed-source tools, which typically lack observability features. Built with privacy in mind, Context Lens operates entirely on local machines without requiring API credentials to leave the network. Its unique features, such as context composition analytics and session tracking, make it an invaluable resource for developers who want to improve their interactions with LLMs, ultimately fostering better performance and cost-efficiency in their AI-driven projects.