Building & Product

How founders use AI for AI in Your Product

The resources behind 13 questions founders actually ask, then the questions themselves, each with a straight answer.

On the AI map, 29 October 2026 Frontier models Open-weight models Decision models

What founders use for ai in your product, ranked by how many answers lean on it.

  1. Video Andrej Karpathy: Software Is Changing (Again) Y Combinator / Andrej Karpathy
  2. Video Harrison Chase on Deep Agents, LangSmith, and Earning Trust NVIDIA AI Podcast (Harrison Chase)
  3. The episode that defined the category thesis; 300 potential billion-dollar companies. ycombinator.com Video Vertical AI Agents Could Be 10X Bigger Than SaaS Y Combinator Lightcone (Garry Tan, Jared Friedman, Harj Taggar, Diana Hu)
  4. Video A Cheeky Pint with Intercom Cofounder Des Traynor Cheeky Pint (John Collison, Stripe)
  5. Video Rahul Vohra on How AI Will Change the Way We Work (Upfront Summit) Upfront Ventures
  6. Video [1hr Talk] Intro to Large Language Models Andrej Karpathy
  7. Video Deep Dive into LLMs like ChatGPT Andrej Karpathy
  8. Video RAG Explained For Beginners KodeKloud
  9. Video Build and Deploy a RAG Chatbot with JavaScript, LangChain.js, Next.js freeCodeCamp (Ania Kubow)
  10. Video How I use LLMs Andrej Karpathy
  11. Video AI Engineer World's Fair 2025: Evals track AI Engineer conference
  12. Video Everything Gets Rebuilt: The New AI Agent Stack Harrison Chase (LangChain)

The questions

Should my startup add AI features, and which ones actually matter to users? Users do not care that a feature uses AI; they care whether it removes a slow, painful, judgment-heavy step from their day. Start from a specific friction po... 21 resources → How do founders ship their first AI feature (APIs, wrappers, RAG in plain terms)? Your first AI feature is usually one API call: send the model your instructions plus the user's input, get text or structured JSON back, and wrap it in your ... 21 resources → How much does it cost to run AI features, and how do I keep costs sane? You pay per token (roughly per word) in and out, so cost scales with usage; a small feature can run on tens of dollars a month while a chat-heavy product can... 22 resources → Which AI model should I build on (GPT, Claude, Gemini, open-source), and how do I avoid locking myself in? There is no best model, only the best one for your task at your price: test the top two or three on your own examples, not benchmark headlines. Today's short... 20 resources → How do I test whether my AI feature actually works before launch (evals, in plain terms)? An eval is just a repeatable test suite for your AI feature: 30-100 real example inputs, the output you expect, and a way to score each run. Start by reading... 18 resources → How do I stop my AI feature from making things up in front of customers? Models hallucinate because they are trained to always answer; your job is to constrain them, not to hope. The biggest wins in order: ground answers in your o... 17 resources → Prompt engineering, RAG, or fine-tuning: which one does my product actually need? Work up the ladder: better prompts cost hours, RAG costs days and adds your own live data, fine-tuning costs weeks and only changes behaviour and style, not ... 18 resources → How do I design AI features people trust (chat vs buttons, streaming, showing the work)? A chat box is rarely the right interface: embedded AI (suggestions inside the existing workflow, one click to accept or reject) builds trust faster because u... 18 resources → What is my moat if I'm building on someone else's model? The model is not your moat and never will be; the moat is everything you wrap around it: proprietary data and feedback loops, deep vertical workflow ownershi... 19 resources → Should I put an AI agent in my product, or is a simple workflow enough? A workflow follows steps you defined, with the model filling in the reasoning slots; an agent decides its own path with tools in a loop. Workflows are cheape... 20 resources → Is it safe to send customer data to AI APIs, and what about privacy laws like India's DPDP Act? The major API providers (OpenAI, Anthropic) do not train on your API data by default, and Anthropic no longer keeps API prompts at all by default, except on ... 18 resources → How should I price AI features: per seat, per use, or per outcome? AI broke flat per-seat pricing because every request has a real compute cost; most AI-native companies now run hybrid pricing: a base subscription plus usage... 20 resources → My AI feature is live. How do I monitor it and make it better with real usage? Log every AI call with its prompt, response, cost, latency, and user feedback; observability tools like Langfuse or LangSmith give you this in an afternoon a... 18 resources →

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