Best LLM & Agent Observability and Evaluation Software with a Free Plan or Free Trial

What is Langfuse?

Langfuse is an open-source LLM engineering platform for tracing, evaluation, prompt management, and metrics. It provides detailed traces of LLM application executions — capturing every LLM call, tool use, retrieval step, and agent action — and links traces to user sessions for production ...

What is Helicone?

Helicone is an open-source LLM observability platform that works as a proxy — developers route their LLM API calls through Helicone's gateway with a single URL change, and it automatically logs every request, tracks cost and latency, enables prompt caching, and provides rate limiting. ...

What is LangSmith?

LangSmith is the LLMOps observability and evaluation platform built by LangChain for teams developing production LLM applications. It provides tracing, debugging, and evaluation for any LLM application — not just LangChain ones. Developers use LangSmith to trace every LLM call and tool ...

What is Arize AI?

Arize AI is a revolutionary Machine Learning Observability Platform to quickly identify and address model and data issues. With a comprehensive analytics suite and no restrictions on model framework, platform, or environment, Arize ensures companies can monitor the performance of their products ...

What is PromptLayer?

Unveiling PromptLayer, the pioneering platform tailored for prompt engineers. This innovative tool is tailored to tackle the complexities that accompany managing GPT requests, marking a paradigm shift in how you analyze, troubleshoot, and delve into these requests. With PromptLayer, you wield ...

What is Galileo?

Galileo is an LLM evaluation and observability platform for testing, monitoring, and guardrailing generative AI applications and agents. It captures traces from an application and scores them using its proprietary evaluation models against research-backed metrics, converting offline evals into ...

What is Braintrust (AI Observability)?

Braintrust is an evaluation and observability platform for teams building production LLM applications and agents. It lets engineers log and trace LLM calls with latency, token, and cost metrics, run structured evals against datasets to score output quality, and replay logged production traces ...

What is Athina AI?

Athina AI provides evaluation and monitoring for LLM applications, with a library of preset evaluators, support for custom ones, and dataset management for running experiments before shipping a prompt or model change. It offers a self-hosted deployment so prompts and completions stay inside the ...

What is Confident AI?

Confident AI is the platform built around DeepEval, an open-source evaluation framework that treats LLM testing like unit testing — assertions over metrics such as faithfulness, answer relevance and contextual precision, runnable in CI. The hosted platform adds dataset curation, regression ...

What is Comet?

Comet is a machine learning experiment tracking and model monitoring platform that integrates with any ML library via a single line of code. It covers the full ML lifecycle from experiment management to production monitoring, and works on both local machines and cloud environments. Data ...

What is Weights & Biases?

Weights & Biases is the ultimate solution for keeping track of your deep learning experiments. This innovative tool allows you to easily record and visualize every aspect of your research, collaborate effortlessly, and centrally store all your inputs and outputs. With the ability to quickly ...