[P]Stop using print() to debug your agents. Here's a 60-second alternative.[P]

In three linesSpanlens, an MIT open-source tool, enables LLM agent debugging by changing a single line of code (baseURL). It traces multi-step calls, integrates OpenAI/Anthropic/Gemini, masks sensitive data, and allows Docker self-hosting without vendor lock-in.

Summary generated by Claude — human-verified