--- title: Manual Tracing, Scores, and Evaluation with Langfuse... description: A hands-on guide to LLM observability using self-hosted Langfuse, covering manual tracing with the low-level API versus decorator-based tracing, attaching... canonical: https://daily.dev/posts/manual-tracing-scores-and-evaluation-with-langfuse-self-hosted--7tcswttul twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Manual Tracing, Scores, and Evaluation with Langfuse (Self-Hosted) | daily.dev og:description: A hands-on guide to LLM observability using self-hosted Langfuse, covering manual tracing with the low-level API versus decorator-based tracing, attaching... og:url: https://daily.dev/posts/manual-tracing-scores-and-evaluation-with-langfuse-self-hosted--7tcswttul og:image: https://api.daily.dev/og/posts/7TCswTTul.png og:image:alt: Manual Tracing, Scores, and Evaluation with Langfuse (Self-Hosted) og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Manual Tracing, Scores, and Evaluation with Langfuse (Self-Hosted) **[PyImageSearch](https://daily.dev/sources/pyimagesearch)** · 25 min read · 0 upvotes · 0 comments ## Summary A hands-on guide to LLM observability using self-hosted Langfuse, covering manual tracing with the low-level API versus decorator-based tracing, attaching custom evaluation scores and quality metrics to traces, and running vLLM health checks before executing any pipeline. The tutorial walks through building explicit trace hierarchies with parent traces and child generation spans, computing lightweight quality scores based on answer length and latency thresholds, and logging structured metadata to the Langfuse dashboard. A dedicated health-check script validates vLLM server availability, model readiness, and generation capability before any tracing begins. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [LLM Observability with Self-Hosted Langfuse and vLLM](https://daily.dev/posts/llm-observability-with-self-hosted-langfuse-and-vllm-lgz1tt3tv) · PyImageSearch · 0 upvotes · 0 comments - [Evaluating Agents via LLM-as-a-Judge in Langfuse](https://daily.dev/posts/evaluating-agents-via-llm-as-a-judge-in-langfuse-3scbxjmmw) · Niklas Heidloff · 1 upvotes · 0 comments - [Error Logs Won't Save You: Why LLM Applications Need Tracing at OmbuLabs Blog](https://daily.dev/posts/error-logs-won-t-save-you-why-llm-applications-need-tracing-at-ombulabs-blog-1ocjirtvv) · RUBYLAND · 0 upvotes · 0 comments - [LangSmith Explained: Debugging and Evaluating LLM Agents](https://daily.dev/posts/langsmith-explained-debugging-and-evaluating-llm-agents-wy5ceqqjb) · DigitalOcean Community · 1 upvotes · 0 comments - [LLM Observability Tools for Reliable AI Applications](https://daily.dev/posts/llm-observability-tools-for-reliable-ai-applications-oy255bw6k) · Machine Learning Mastery · 1 upvotes · 0 comments --- Tags: [#llm](https://daily.dev/tags/llm), [#llm-observability](https://daily.dev/tags/llm-observability), [#python](https://daily.dev/tags/python), [#vllm](https://daily.dev/tags/vllm) [View this post on daily.dev](https://daily.dev/posts/manual-tracing-scores-and-evaluation-with-langfuse-self-hosted--7tcswttul) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Manual Tracing, Scores, and Evaluation with Langfuse (Self-Hosted)","url":"https://daily.dev/posts/manual-tracing-scores-and-evaluation-with-langfuse-self-hosted--7tcswttul","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/manual-tracing-scores-and-evaluation-with-langfuse-self-hosted--7tcswttul"},"datePublished":"2026-05-25T12:53:59.865Z","dateModified":"2026-07-16T02:12:36.770Z","description":"A hands-on guide to LLM observability using self-hosted Langfuse, covering manual tracing with the low-level API versus decorator-based tracing, attaching...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/74cc3d9aa3f8fa27db38bda3c278edbb?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/74cc3d9aa3f8fa27db38bda3c278edbb?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"PyImageSearch","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"PyImageSearch","logo":"https://media.daily.dev/image/upload/t_logo,f_auto/v1/logos/33ddc48b99ee47eb9283ef1fdcff3095","url":"https://daily.dev/sources/pyimagesearch"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/manual-tracing-scores-and-evaluation-with-langfuse-self-hosted--7tcswttul","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"llm,llm-observability,python,vllm","timeRequired":"PT25M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"PyImageSearch","item":"https://daily.dev/sources/pyimagesearch"},{"@type":"ListItem","position":3,"name":"Manual Tracing, Scores, and Evaluation with Langfuse (Self-Hosted)"}]} ```