StartupY Combinator (S26)
Agnost AI
Monitoring and continuous improvement for AI agents: detects failures and opens fix PRs.
Agnost AI launched on Hacker News in July 2026 with product analytics drawn from agent conversations, such as rage-prompting and rephrasing. Its site now reads "Monitoring and Continuous Improvement for AI Agents": it detects failures and opens pull requests that fix them. Y Combinator S26.
Neighbours in the directory
San Francisco, CA · Est. 2022
The de-facto standard toolkit for building LLM applications and agents.
LangChain makes the LangChain framework and LangGraph, the low-level orchestration standard for stateful, controllable agents, plus the LangSmith platform for tracing, evaluating and monitoring them in production.
~$75M raised
San Francisco, CA · Est. 2023
Enterprise-grade evals, data and AI gateway.
Braintrust turns prompts and agent traces into testable datasets and CI, plus an inference gateway — helping teams measure whether harness changes actually improve agent quality.
Berkeley, CA · Est. 2020
Observability and evaluation for AI — makers of OSS Phoenix.
Arize traces and evaluates LLM and agent systems in production; their open-source Phoenix tracer is a common instrumentation choice for agent harnesses that need to be debuggable.
Sources
Verified Oct 29, 2026