Langfuse Has a Free API — Open-Source LLM Observability and Tracing

What if you could trace every LLM call — input, output, latency, cost, and feedback — in one dashboard? Langfuse is open-source LLM observability. Like Datadog for AI apps. Tracing — every LLM call with cost and latency Prompt management — version and A/B test prompts Evaluations — model-based and human scoring Free tier — 50K observations/month An AI startup discovered one feature used 60% of tokens for 5% of users. Optimized prompt, costs dropped from $3K to $1.2K/month. Visit langfuse.com — open source, self-hostable. Need custom data pipelines or scraping solutions? Check out my Apify actors or email me at spinov001@gmail.com for custom solutions.