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About
Humanloop was the first dedicated development platform for LLM applications, setting industry standards for how engineering and product teams build, manage, and evaluate AI-powered software. The platform brought together three core capabilities: prompt management, AI evaluation, and LLM observability — giving teams a unified workspace to iterate on prompts with version control, run systematic evaluations to measure model quality, and monitor live LLM calls in production. Designed for developers and AI teams at companies pushing the frontier of AI adoption, Humanloop reduced the complexity of shipping reliable LLM features by providing structured workflows, collaboration tools, and data-driven feedback loops. Teams could compare model outputs side by side, define custom evaluation metrics, log and trace every LLM interaction, and systematically improve prompts over time without losing history. Humanloop attracted backing from notable investors including Albion, Index Ventures, Y Combinator, and LocalGlobe, and worked closely with enterprise customers to shape best practices in LLM application development. In 2025, the entire Humanloop team joined Anthropic to help accelerate safe AI adoption at a larger scale. The Humanloop platform has been sunset, and customers were supported through the transition.
Key Features
- Prompt Management: Version-controlled prompt editor that lets teams iterate, compare, and deploy prompts across models without losing history.
- AI Evaluation: Systematic evaluation framework to define custom metrics, run batch tests, and measure LLM output quality over time.
- LLM Observability: Full logging and tracing of every LLM call in production, enabling teams to monitor costs, latency, and output quality.
- Collaborative AI Development: Shared workspace for cross-functional teams to collaborate on prompt design, review evaluations, and ship AI features together.
- Model Comparison: Side-by-side comparison of outputs across different models and prompt versions to inform model selection decisions.
Use Cases
- Engineering teams managing and versioning prompts across multiple LLM models in a shared, collaborative workspace.
- AI product teams running systematic evaluations to benchmark model quality before and after prompt or model changes.
- DevOps and MLOps teams monitoring LLM call logs, latency, and costs in production environments.
- Enterprises building reliable, auditable AI features that require traceable prompt history and performance metrics.
- Research and development teams comparing outputs across different foundation models to select the best fit for a given task.
Pros
- Industry-first LLM platform: Humanloop was the first purpose-built platform for LLM application development, establishing best practices adopted widely across the industry.
- End-to-end workflow: Unified prompt management, evaluation, and observability in a single platform, reducing tool sprawl for AI engineering teams.
- Enterprise-grade reliability: Trusted by enterprise customers pushing the boundaries of AI adoption, with strong investor backing from YC and Index Ventures.
Cons
- Platform has been sunset: Following the team's acquisition by Anthropic, the Humanloop platform is no longer available for new customers.
- Enterprise pricing: Humanloop was primarily positioned as an enterprise tool, making it less accessible for individual developers or small teams on tight budgets.
Frequently Asked Questions
What happened to Humanloop?
The Humanloop team joined Anthropic in 2025 to continue their mission of enabling safe and rapid AI adoption. The Humanloop platform has been sunset, and customers were supported through the transition.
What did Humanloop do?
Humanloop was the first development platform for LLM applications. It provided tools for prompt management (versioning and deployment), AI evaluation (systematic output quality testing), and LLM observability (logging and monitoring of production AI calls).
Who used Humanloop?
Humanloop was used by engineering and product teams at companies building AI-powered applications, ranging from startups to enterprise organizations pushing the boundaries of LLM adoption.
Why did Humanloop join Anthropic?
As AI progress accelerated, the Humanloop team believed Anthropic was the ideal home to amplify their impact and further their shared mission of enabling safe and rapid AI adoption at scale.
Is there a migration guide for Humanloop customers?
Yes, Humanloop published a Migration Guide on their website to help existing customers transition away from the platform as smoothly as possible following the Anthropic acquisition.
