--- title: "langtrace vs trulens" type: "comparison" canonical_url: "https://www.graphcanon.com/compare/scale3-labs-langtrace-vs-truera-trulens" tools: ["scale3-labs-langtrace", "truera-trulens"] --- # langtrace vs trulens Neutral, constraint-first comparison with live GitHub stats. | | [langtrace](/tools/scale3-labs-langtrace.md) | [trulens](/tools/truera-trulens.md) | | --- | --- | --- | | Tagline | Open Source Observability for LLM Applications | Evaluation and Tracking for LLM Experiments and AI Agents | | Stars | 1,213 | 3,429 | | Forks | 124 | 309 | | Open issues | 1 | 104 | | Language | TypeScript | Python | | Adopt for | Langtrace is an open-source observability software that provides real-time monitoring and performance insights for applications leveraging LLM APIs, vector databases, and LLM-based frameworks through Open Telemetry. It's | TruLens provides fine-grained instrumentation and agentic evaluations to identify failure modes in LLM experiments. It supports multiple providers and integrates with various app frameworks. | | Persona | - | - | | Runtime | - | - | | License | AGPL-3.0 implies that any changes made to the software must be released under the same license, which might limit its use in commercial products closed off to users. | MIT | | Categories | Evaluation & Observability | Evaluation & Observability | ## Trust and health _Sourced signals - not a safety guarantee. No winner column._ | | [langtrace](/tools/scale3-labs-langtrace.md) | [trulens](/tools/truera-trulens.md) | | --- | --- | --- | | Maintenance | Slowing (36%) | Active (82%) | | Days since push | 232d | 7d | | Open issues (now) | 1 | 104 | | Security scan | No lockfile | No criticals | | Full report | [trust report](/tools/scale3-labs-langtrace/trust.md) | [trust report](/tools/truera-trulens/trust.md) | **Typed relationship:** langtrace _(alternative)_ trulens Both LANGTRACE and TruLens provide open-source observability solutions for LLMs, helping with monitoring and evaluation during development phases. ## Shared compatibility - **Python**: [langtrace](/tools/scale3-labs-langtrace.md) - Python runtime; [trulens](/tools/truera-trulens.md) - Python runtime ## Decision facts: langtrace - **Requirements:** Self-hosting is available as an option if desired. - **Adopt for:** Langtrace is an open-source observability software that provides real-time monitoring and performance insights for applications leveraging LLM APIs, vector databases, and LLM-based frameworks through Open Telemetry. It's - **License detail:** AGPL-3.0 implies that any changes made to the software must be released under the same license, which might limit its use in commercial products closed off to users. ## Decision facts: trulens - **Pricing:** freemium - TruLens offers its core functionality as open-source under the MIT license. However, additional services and integrations might come with commercial tiers not specified in the repository. - **Requirements:** Min 4 GB RAM; TruLens requires installation via pip for Python and supports multiple integrations with LLM providers and app frameworks through additional packages. - **Adopt for:** TruLens provides fine-grained instrumentation and agentic evaluations to identify failure modes in LLM experiments. It supports multiple providers and integrates with various app frameworks. ## Choose when ### Choose langtrace if… - langtrace is primarily TypeScript; trulens is Python. - License: langtrace is AGPL-3.0, trulens is MIT. - Requirements: Self-hosting is available as an option if desired.. - Both LANGTRACE and TruLens provide open-source observability solutions for LLMs, helping with monitoring and evaluation during development phases. - Tags unique to langtrace: evaluations, llm, ai, datasets. - langtrace ships Docker support for self-hosted deployment. - - When you are developing or managing applications that heavily rely on LLM APIs and want to capture, debug, and analyze traces and metrics in real-time using Open Telemetry. ### Choose trulens if… - trulens is primarily Python; langtrace is TypeScript. - License: trulens is MIT, langtrace is AGPL-3.0. - Pricing: TruLens offers its core functionality as open-source under the MIT license. However, additional services and integrations might come with commercial tiers not specified in the repository.. - Requirements: Min 4 GB RAM; TruLens requires installation via pip for Python and supports multiple integrations with LLM providers and app frameworks through additional packages.. - Both LANGTRACE and TruLens provide open-source observability solutions for LLMs, helping with monitoring and evaluation during development phases. - Tags unique to trulens: neural-networks, llm-eval, agent-evaluation, machine-learning. - - When you need a stack-agnostic tool to systematically evaluate your LLM applications, especially those involving complex interactions such as retrieval-augmented generation (RAG) or multi-tool based ## When NOT to use langtrace - - If you need proprietary features absent from the AGPL-3.0 open-source license, as Langtrace's nature may limit its use in closed or commercial projects. - - For organizations with existing observability solutions deeply integrated into their infrastructure that do not benefit significantly from adding an additional layer of monitoring. ## When NOT to use trulens - - If your project strictly adheres to one model and provider which meets all your observation needs without requiring detailed performance metrics or cross-provider comparisons - - When you are working on very simple LLM applications that do not involve complex prompts, retrievers, or multiple knowledge sources where such fine-grained evaluation is unnecessary ## Common questions ### What is the difference between langtrace and trulens? langtrace: Open Source Observability for LLM Applications. trulens: Evaluation and Tracking for LLM Experiments and AI Agents. See the comparison table for live GitHub stats and shared categories. ### When should I choose langtrace over trulens? Choose langtrace over trulens when langtrace is primarily TypeScript; trulens is Python; License: langtrace is AGPL-3.0, trulens is MIT; Requirements: Self-hosting is available as an option if desired.; Both LANGTRACE and TruLens provide open-source observability solutions for LLMs, helping with monitoring and evaluation during development phases; Tags unique to langtrace: evaluations, llm, ai, datasets; langtrace ships Docker support for self-hosted deployment; - When you are developing or managing applications that heavily rely on LLM APIs and want to capture, debug, and analyze traces and metrics in real-time using Open Telemetry. ### When should I choose trulens over langtrace? Choose trulens over langtrace when trulens is primarily Python; langtrace is TypeScript; License: trulens is MIT, langtrace is AGPL-3.0; Pricing: TruLens offers its core functionality as open-source under the MIT license. However, additional services and integrations might come with commercial tiers not specified in the repository.; Requirements: Min 4 GB RAM; TruLens requires installation via pip for Python and supports multiple integrations with LLM providers and app frameworks through additional packages.; Both LANGTRACE and TruLens provide open-source observability solutions for LLMs, helping with monitoring and evaluation during development phases; Tags unique to trulens: neural-networks, llm-eval, agent-evaluation, machine-learning; - When you need a stack-agnostic tool to systematically evaluate your LLM applications, especially those involving complex interactions such as retrieval-augmented generation (RAG) or multi-tool based. ### When should I avoid langtrace? - If you need proprietary features absent from the AGPL-3.0 open-source license, as Langtrace's nature may limit its use in closed or commercial projects. - For organizations with existing observability solutions deeply integrated into their infrastructure that do not benefit significantly from adding an additional layer of monitoring. ### When should I avoid trulens? - If your project strictly adheres to one model and provider which meets all your observation needs without requiring detailed performance metrics or cross-provider comparisons - When you are working on very simple LLM applications that do not involve complex prompts, retrievers, or multiple knowledge sources where such fine-grained evaluation is unnecessary ### Is langtrace or trulens more popular on GitHub? trulens has more GitHub stars (3,429 vs 1,213). Stars measure visibility, not whether either tool fits your constraints. ### Are langtrace and trulens open source? Yes - both are open-source projects on GitHub (langtrace: AGPL-3.0, trulens: MIT). ### Where can I find alternatives to langtrace or trulens? GraphCanon lists graph-backed alternatives at /tools/scale3-labs-langtrace/alternatives and /tools/truera-trulens/alternatives (/tools/scale3-labs-langtrace/alternatives.md, /tools/truera-trulens/alternatives.md), ranked by typed relationship edges rather than popularity votes. ### Is there a machine-readable version of this comparison? Yes. The markdown twin at /compare/scale3-labs-langtrace-vs-truera-trulens.md mirrors this page for agents and LLM crawlers, with the same stats table and FAQ answers. ### Which is better maintained, langtrace or trulens? langtrace: Slowing. trulens: Active. Compare maintenance labels, days since push, and release cadence in the trust section below - stars alone do not measure maintenance. ### Where are the full trust reports for langtrace and trulens? GraphCanon publishes per-repo trust reports with dated maintenance, provenance, and scan summaries: langtrace: /tools/scale3-labs-langtrace/trust; trulens: /tools/truera-trulens/trust. --- **Machine-readable endpoints** - JSON: [`/api/graphcanon/graph?tool=scale3-labs-langtrace`](/api/graphcanon/graph?tool=scale3-labs-langtrace) - LLM index: [/llms.txt](/llms.txt) - Full corpus: [/llms-full.txt](/llms-full.txt) _GraphCanon - The knowledge graph for AI development. https://www.graphcanon.com/_