Yes, exactly - they are different layers. I am not comparing Langfuse and LiteLLM as if they are the same category of tool. The point of the article is to compare where each tool sits in the LLM workflow: Langfuse helps you observe, trace, debug, and evaluate what happened. LiteLLM sits closer to the request path as a gateway/proxy for routing, provider abstraction, spend tracking, and budgets. Runcap is narrower again: it focuses on AI coding agent runs - capping routed spend before it compounds, and using a Proof Gate to decide whether an AI-generated PR earned merge eligibility. So the comparison is not “which one replaces the others?” It is: What problem are you trying to solve? Observability after the run? Routing and budget control across providers? Or mission-level control and proof before trusting an AI-generated code change?
