The essential tools for evaluating, testing, and monitoring AI and LLM applications. From prompt testing to production observability, these platforms help you ship reliable AI features.
The LLM product development platform
Freeplay is a comprehensive platform for building, testing, and optimizing LLM-powered applications. It provides prompt management, A/B testing, evaluation frameworks, and collaboration tools for teams building AI products. With version control for prompts, automated testing pipelines, and detailed analytics, Freeplay helps teams ship better AI features faster.
Product teams building LLM-powered features who need structured prompt management, testing, and collaboration
Free tier available, Pro plans from $99/month
The enterprise AI evaluation platform
Braintrust is an enterprise-grade platform for evaluating and improving AI applications. It provides comprehensive evaluation frameworks, logging, tracing, and analytics for LLM-powered products. With support for custom evaluators, regression testing, and detailed observability, Braintrust helps teams maintain quality as they scale AI features.
Enterprise teams who need rigorous evaluation frameworks and observability for production AI systems
Free tier available, Enterprise pricing on request
The LLM application development platform by LangChain
LangSmith is LangChain's platform for debugging, testing, evaluating, and monitoring LLM applications. It provides end-to-end tracing of LLM calls, dataset management, evaluation tools, and production monitoring. Deeply integrated with LangChain but works with any LLM framework, LangSmith gives full visibility into your AI application's behavior.
Teams using LangChain or building complex LLM applications who need full observability and debugging
Free tier available, Plus from $39/month, Enterprise on request
ML and LLM observability for production AI
Arize AI is a comprehensive observability platform for machine learning and LLM applications in production. It provides monitoring, troubleshooting, and evaluation tools for AI systems at scale. With support for embeddings, prompt/response analysis, and automated issue detection, Arize helps teams maintain reliable AI products.
ML/AI teams running production systems who need comprehensive observability and automated monitoring
Free tier available, Pro from $50/month, Enterprise on request
The prompt engineering and evaluation platform
Humanloop is a platform for prompt engineering, evaluation, and monitoring of LLM applications. It provides tools for prompt versioning, A/B testing, human feedback collection, and automated evaluation. With a focus on iterative improvement and collaboration, Humanloop helps teams optimize their AI features continuously.
Teams focused on prompt optimization who need structured workflows for iterating and improving prompts
Free tier available, Pro from $99/month
Automated testing and evaluation for LLMs
Patronus AI provides automated testing and evaluation tools specifically designed for LLM applications. It offers pre-built evaluators for common issues like hallucinations, toxicity, and PII leakage, along with custom evaluation capabilities. With continuous monitoring and regression testing, Patronus helps teams ship reliable AI products.
Teams prioritizing AI safety and reliability who need automated detection of hallucinations, toxicity, and data leakage
Contact for pricing
The first platform built for prompt engineers
PromptLayer is a prompt management and observability platform that tracks, manages, and optimizes LLM requests. It provides a visual interface for prompt versioning, request logging, and performance analytics. With features for collaboration and A/B testing, PromptLayer makes prompt engineering more systematic and data-driven.
Prompt engineers and teams who want to systematically track, version, and optimize their prompts
Free tier available, Pro from $29/month
Open source LLM evaluation and testing
Promptfoo is an open-source tool for testing and evaluating LLM outputs. It provides a CLI and library for running evaluations against multiple prompts and models, with support for custom assertions and automated scoring. Self-hosted and privacy-friendly, Promptfoo is ideal for teams who want control over their evaluation pipeline.
Developers who want open-source, self-hosted LLM evaluation with full control over their testing pipeline
Free and open source, Cloud version available
AI observability for reliable ML and LLMs
WhyLabs is an AI observability platform that provides monitoring, security, and evaluation for ML and LLM applications. Built on the open-source whylogs library, it offers data quality monitoring, model performance tracking, and LLM-specific features like hallucination detection and prompt injection monitoring.
Teams needing comprehensive ML/AI observability with a focus on data quality, security, and open-source foundations
Free tier available, Growth from $200/month
AI quality intelligence for LLM applications
Galileo is an AI quality intelligence platform that helps teams debug, evaluate, and improve LLM applications. It provides automated evaluation metrics, hallucination detection, and root cause analysis for LLM failures. With features for data curation and fine-tuning optimization, Galileo helps teams build more reliable AI products.
Teams focused on LLM quality and reliability who need deep insights into model behavior and failure modes
Free tier available, Pro pricing on request
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