The article introduces Dev-Agent-Lens, a tool designed to enhance observability and tracing for Claude Code, a platform known for code generation and analysis. Recognizing the limitations of conventional logs, Dev-Agent-Lens employs a proxy-based architecture using LiteLLM to centralize model routing and monitoring, while integrating OpenTelemetry and OpenInference to capture comprehensive trace data. This tool allows users to evaluate workflows for correctness, relevance, and success by examining detailed spans of model prompts, tool inputs, and outputs, thereby simplifying debugging and optimizing performance. It also helps identify cost overruns by tracking token usage, enabling users to manage budgets effectively and prevent quality degradation. The tool is versatile, supporting various real-world use cases such as security analysis, incident response, and code review, with instructions available for getting started with its implementation.