{"categories":[{"label":"Quality Assurance","url":"https://skillfed.io/packages/category/software-development-quality-assurance/3"}],"enrichment":{"capability":"Instruments LLM applications with OpenTelemetry-native tracing and evaluates them with LLM-based judges that explain their reasoning, capturing latency, cost, and quality per step.","skillfed_tags":["llm-evaluation","observability","agent-debugging"],"use_cases":["Instrument a RAG pipeline to trace retrieval, ranking, and generation steps, then score groundedness and context relevance per query.","Compare two versions of an agent by running both against a dataset and measuring latency, token cost, and evaluation scores side-by-side.","Debug agent failures by examining structured traces that show which tool was called, what arguments were passed, and where reasoning broke down.","Evaluate agentic systems for plan quality and tool selection by running purpose-built judges that flag redundant steps or incorrect tool choices.","Export traces to an existing observability backend (Datadog, Grafana) while running evaluations in TruLens without duplicating instrumentation.","Batch-evaluate a historical dataset of app runs using the Run API to compute metrics offline and identify systematic quality issues."],"what_it_does":"TruLens is an instrumentation and evaluation framework for LLM-based applications built on OpenTelemetry. It decorates functions to capture structured traces of every step\u2014retrieval, LLM calls, tool invocations\u2014recording latency, tokens, and cost per operation. Once traces are collected, the package evaluates them using LLM judges that score and explain their reasoning, enabling you to identify where applications fail, compare versions, and measure quality tradeoffs against cost.\n\nThe package ships with seven agentic evaluators (LogicalConsistency, ExecutionEfficiency, PlanAdherence, ToolSelection, and others) and supports both inline evaluation as your app runs and batch evaluation over pre-collected datasets. Because tracing is OpenTelemetry-native, traces are portable to any OTLP-compatible backend\u2014Jaeger, Grafana Tempo, Datadog\u2014making it interoperable with existing observability infrastructure. Runtime dependencies include SQLAlchemy for storage, Pydantic for validation, and OpenTelemetry libraries for instrumentation.","worth_installing":"Yes. TruLens is actively maintained, has no known vulnerabilities, and solves a real problem for LLM application teams: making agent behavior traceable and measurable. The OpenTelemetry foundation ensures portability, and the built-in evaluators are benchmarked against human annotations. Install it if you need to instrument and evaluate LLM apps; skip it if you only need basic logging."},"id":"trulens-core","links":{"html":"https://skillfed.io/packages/trulens-core","md":"https://skillfed.io/packages/trulens-core.md","pypi":"https://pypi.org/project/trulens-core/"},"maintenance":{"status":"active"},"meta":{"latest_release":"2026-08-14","license_spdx":null,"license_treatment":"permissive","name":"trulens-core","python_support":"supports_current","summary":"Library to systematically track and evaluate LLM based applications."},"popularity":{"monthly_downloads":126116,"position":11789,"tier":"top_15000"},"security":{"n_vulnerabilities":0},"version":"2.13.0"}