Hendrix Liu

Two years after graduating, I went back to UIUC and spoke to hundreds of students with my co-founder Andy and YC partner Pete. Still feels unreal. Not long ago I was sitting in the audience - now I was on stage sharing our story. We started with $0, built while in school, went through YC, survived 2 years on $500K, and became ramen profitable. Most grateful part: I get to build with my best friends/college roommates, and now Keywords AI is used by hundreds of AI teams in real products. Illinois still feels like home. Can’t wait to be back.

AI observability platforms raised $1B+ to reinvent print debugging for the agent era. Reading traces manually is not a scalable production workflow. We think the stack should catch issues itself. Meet Respan.

If your team still does manual prospecting, this is worth a look. describe your target, it handles the rest

@kathrynwu1 @openmartai for founder-led or early GTM teams, this removes most of the manual outbound work!

Today we launched OpenClaw for Sales. It combines @openmartai’s data, LinkedIn data, and top data sources to do the work for you. Used by teams like Whatnot, DoorDash, Alibaba, and many others. Try for free: tinyurl.com/3fjczmtc or DM me for an invite code.

Respan Launch Week, Day 5 🚀 Introducing AI Gateway Limits and Alerts. LLM costs can get out of control fast in production, especially as traffic grows across models, API keys, and apps. Now you can set limits directly in Respan AI Gateway: - Alerts via email or Slack - Recurring budgets for LLM usage - Limits by API key or model - Controls for cost, requests, or tokens When a limit is exceeded, you can block the request or send a warning. Built for teams that want to move fast with clear cost controls. Try it today!

Respan Launch Week, Day 4: Introducing Respan Integrations Most teams still spend days setting up observability. That’s why we invested heavily in Respan Integrations. We support major LLM and agent frameworks like OpenAI, Anthropic, Gemini, LangChain, Vercel AI, and Pydantic AI, with more being added. Run 'npx [at]respan/cli setup' and start tracing in minutes, not days.

Respan Launch Week, Day 3: introducing @RespanAI Agent, CLI, and MCP. Three ways to stop doing AI engineering by hand: → Agent: ask it to build an evaluator, fix a prompt, or find the root cause of a bad trace on the platform. → CLI: npx respan@cli setup - auth, framework detection, and tracing in one command. → MCP: plug Respan into Claude Code, Cursor, or anything that speaks MCP. Same data, same access, wherever you work.

tomorrow we kick off the 3rd cohort of startups we've invited to use Autobuild, the internal tool driving the insane autonomous build velocity at @obvious (nearing 1000 PRs a day from 10 engineers) each co is shipping 12 weeks of roadmap this is the frontier, build accordingly

We built “Scratch” for AI evals on @RespanAI. Right now evals are: – LLM-as-judge – humans – random scripts All disconnected. But real systems need logic: if score < threshold → send to human if edge case → add to dataset if quality drops → retry / alert So we made evaluators programmable - with the workflow builder we think is the best. Today we’re launching the first workflow-based evals for AI products. Not just scoring - deciding what happens next. Run it on your real traffic. Try 10k evals free today.

Respan Launch Week, Day 2: Evals Evals are one of the hardest parts of building AI applications. It is not because teams cannot run them. It is because they are hard to structure, hard to compare, and even harder to improve over time. So teams end up guessing. Did this prompt actually get better? Is this model really an improvement? We built Evals in Respan to make this systematic. You define: - what you want to test, such as prompts, models, or configs - the dataset, from production logs or test cases - the evaluators, whether LLM, code, human, or a mix Then you run experiments and compare results side by side. Same inputs. Same evaluation. Clear answers. No more guessing. Start running your first eval.

read the full blog here: respan.ai/blog/monitors-…

Respan Launch Week, Day 1: we’re launching Monitors for AI products. AI teams already track the basics in production: - error rate - cost - latency - token usage The problem is not measuring them. The problem is reacting fast enough. A model update can increase error rate. A prompt change can raise cost. Latency can drift over time. Most teams do not catch these problems right away. Monitors turn these metrics into real-time alerts. You set the thresholds that matter, and get notified as soon as something crosses the line. This gives teams a faster way to spot issues and respond before they grow. Activate your first monitor now.

join the waitlist for our launch week here: respan.ai/launch-week

The first launch week in @RespanAI's history starts soon. We'll ship a new feature every day from April 20 to 24. This is our biggest product update yet. It will reshape how teams handle AI observability and evaluations. Get ready. Next week is going to be a big one for us!

"Opus 4.6 doesn't like rocks lol" A user on r/ClaudeAI found Claude can't complete sentences about minerals ending in "-ite." It loops, generates a fake mineral, gets corrected, and does it again. That's 1 of 25 ways LLM apps silently fail in production. Warm up of Respan's launch fortnight: our launch week, but we make it TWO.

@roshan_k_ yeah that’s the only way i could come up with too. gonna build one tonight

@HendrixLiu29208 Claude code 😅

what’s the best way to go through all the resumes i’ve received? i opened a role last friday, and now i’m getting 150+ resumes a day in my inbox there’s no way i can read through all of them one by one

We’re hosting a welcome event for YC P26 founders with @Rippling, @Fondocom, @ArgaLabs, and @MongoDB. Come hang out, have fun, and meet other YC founders. You’ll also hear from YC alumni about best practices for growing during the batch and avoiding common mistakes. Come chat with us this Thursday! Event link 👇

@darian314 @Nasdaq 🚀🚀🚀

Thank you @NASDAQ!

@wuseokjung_ @RespanAI @GradientVC Thank you Josh!❤️

@RespanAI @GradientVC Let’s go @HendrixLiu29208 and team!!

Today we’re announcing that Respan has raised a $5M seed round led by @GradientVC. We’re building the self-driving observability, evals, and gateway for AI agents. 100+ teams already use Respan. 1B+ logs/month. 2T+ tokens/month. And we’re just getting started.