Regent

What it does

Reliability is the next frontier for AI apps. We were already shipping MVPs. It's time to turn them into products. Existing observability tools do for LLM apps what logs did for conventional ones: they tell you what happened, not what changed. Regent is the first regression testing layer for agentic apps. It can run semantic diffs on your agent's entire execution trace for any critical inputs, all before you merge the PR. Posts the results right in your Github. No more finding out from users.

Automated Evals for AI Agents

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  AI Observability by OpenObserveAug 2026 · openobserve.ai · ▲317

  OpenTelemetry-native observability for agents and LLMs

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  Progress AI ObservabilityAug 2026 · telerik.com · ▲168

  Hi HN! We’re the team behind Fiddler, and we recently built an Agent Cache feature. It works by capturing an LLM request/response pair and, once caching is enabled, serving subsequent matching calls locally so duplicate requests never hit the provider. It’s meant to reduce three pains that show up together in agent development: token cost, feedback-loop latency, and output non-determinism. We’d love to hear your thoughts.

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  QualGentDec 2025 · qualgent.ai · ▲296

  I built an AI agent that can do mobile app QA after working at Google for years and waiting weeks for QA results. It runs on real devices and uses an ensemble of agents (including computer use) to test like a human. Happy to answer questions and hope it helps app devs ship faster without bugs!

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  TrailsJan 2026 · trails-red.vercel.app · ▲81

  Hey all, Justin here. I previously built Phind, the AI search engine for developers. One of the biggest problems we had there was figuring out what went wrong with bad searches. We had tons of searches per day, but less than 1% of users gave any explicit feedback. So we were either manually digging through searches or making general system improvements and hoping they helped. This problem gets harder with agents. Traces are longer and more complex. It takes more effort to review them, so I'm building a tool that lets you analyze LLM outputs directly to help developers of LLM apps and agents…

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  TracciaAug 2026 · traccia.ai · ▲197

  AI applications are becoming agents, which has started to take autonomous decisions. There are plenty of tools and platform available to trace, and observe what an agent or llms calls does. They are good in what they do, but tracing and observability isnt enough for AI agents era. We need a solution that can help you observe, evaluate, create run time policies to govern and finally audit the actions of the agent. We built Traccia to solve this problem. The good part, all of these can be achieved by just writing few lines of code. Traccia has an open-sourced sdk that can work with your…

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  Langtrace AI2024 · langtrace.ai · ▲119

  Improve your LLM apps with open-source observability tool

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  Spira Maxima▲578

  Video model that turns script into viral social media videos

  AI · 18d ago · spira.ai

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  Rill Browser▲540

  The browser where Claude Code and Codex work beside you

  AI · 17d ago · rill.love

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  Germany's new sovereign AI model Kolibri▲424

  Kolibri is Aleph Alpha

  AI · 19d ago · tej.as

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  Giving Opus 5.5 a simulated paint canvas▲392

  Paintings by AI models: programs run through a simulation of oil paint.

  AI · 21d ago · stillwet.art

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  PixVerse R2▲381

  A real-time world model you can explore and change

  AI · 29d ago · world.pixverse.video

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  Beam.win▲377

  Run AI agents on one Mac and use its windows on another

  AI · 4d ago · beam.win

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  Brila▲1,364

  One-page websites from real Google Maps reviews

  AI · Apr 2026 · brila.ai

• AG
  A game where you build a GPU▲964

  Thought the resources for GPU arch were lacking, so here we are

  Life & fun · Apr 2026 · jaso1024.com

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  I built a tiny LLM to demystify how language models work▲915

  Built a ~9M param LLM from scratch to understand how they actually work. Vanilla transformer, 60K synthetic conversations, ~130 lines of PyTorch. Trains in 5 min on a free Colab T4. The fish thinks the meaning of life is food. Fork it and swap the personality for your own character.

  AI · Apr 2026 · github.com

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  Fathom 3.0▲800

  AI meeting notes: now bot-free, in ChatGPT & Claude + more

  AI · Apr 2026 · fathom.ai

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  Brutalist Concrete Laptop Stand (2024)▲786

  I made a laptop stand out of solid concrete, in the style of brutalist architecture, with themes of urbex and urban decay

  Life & fun · Apr 2026 · sam-burns.com

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  I built a frontpage for personal blogs▲783

  With social media and now AI, its important to keep the indie web alive. There are many people who write frequently. Blogosphere tries to highlight them by fetching the recent posts from personal blogs across many categories. There are two versions: Minimal (HN-inspired, fast, static): https://text.blogosphere.app/ Non-minimal: https://blogosphere.app/ If you don't find your blog (or your favorite ones), please add them. I will review and approve it.

  AI · Apr 2026 · text.blogosphere.app