Design like Karpathy is watching - Zeke Sikelianos, Replicate

Introduction and Context 00:03

  • Speaker jokes with audience to warm up and identifies Replicate employees in the room
  • Zeke Sikelianos introduces himself, shares his GitHub/X handle, and describes Replicate as a cloud platform for running AI models from open source and proprietary sources, including custom ones

Who is Andrej Karpathy? 01:40

  • Karpathy is an AI researcher with experience at Google, OpenAI, Tesla, and more recently Eureka Labs, an educational platform
  • He is notable for his accessible YouTube talks, popularizing concepts like "vibe coding" and describing "English" as the hottest programming language
  • Karpathy wrote the "software 2.0 manifesto," predicting a future where machine learning models write code more effectively than humans

The MenuGen Experiment and Developer Experience Pain Points 02:50

  • Karpathy created MenuGen (Menuguen), a web app for generating menu item images from text, useful for those unfamiliar with menu languages or terminology
  • Development was fun locally but became much more complex and frustrating when deployed due to multiple platform pain points
  • Karpathy published a blog post describing his frustrations, highlighting issues with outdated documentation, API changes, rate limits, and onboarding—even for paid users
  • Replicate was acknowledged alongside major companies, underscoring shared developer experience shortcomings

Improving Replicate for LLMs and Developers 05:19

  • Replicate teams embraced "llm.text" to provide documentation in markdown and plaintext formats, making it easy for LLMs to parse
  • Added features: model pages have a button to copy markdown docs or send them directly to Claude or ChatGPT for interactive exploration
  • The approach makes documentation more interactive for both humans and LLMs

Curl and API Usability for LLMs 07:06

  • Karpathy emphasizes that LLMs prefer API documentation as simple curl commands rather than complex interfaces
  • Curl, despite being old and basic, is accessible and fully describes an API request, making it ideal for both humans and LLMs

Cog and llm.ext Documentation for Ease of Integration 08:21

  • Cog, an open-source tool, helps package machine learning models into Docker containers with standardized APIs
  • All Cog docs are available in a single llm.ext file, so editors can consume them for context—enabling LLMs to use and modify code more effectively

LLMs as the Primary Audience 09:20

  • The primary audience for product documentation and APIs is now language models, not just human developers
  • Having machine-readable, up-to-date OpenAPI schemas is essential to ensure LLMs can access and understand API functionalities

The Role and Implementation of MCP 09:56

  • MCP (Model-Connected Plugin, inferred from context) bridges OpenAPI schemas and LLMs, allowing LLMs to interact directly with APIs
  • Installation is straightforward, involving only an API token and a line of JSON in dev settings; enables tools like Claude, GitHub Copilot, and VS Code to use Replicate's API through MCP
  • MCP facilitates discovery, scaffolding, and interactive development via language models, powered by a well-documented OpenAPI schema

Lessons Learned and Best Practices Post-Karpathy Blog 13:11

  • Accept payments flexibly: blocking legitimate new users for rapid API use is a mistake—enable credit-based or pay-to-unlock systems
  • Always document new features before considering them done; documentation now also targets LLM consumption
  • Output documentation and data in formats most accessible to LLMs (markdown/plaintext rather than flashy HTML)
  • Use established, "boring" technologies so LLMs trained on conventional software can generate/use code effectively
  • Design APIs with concise, information-dense outputs that are easy for LLMs to handle (avoid overloading with unnecessary data)

Q&A: Docs, Discovery, and LLMs in Decision-Making 17:14

  • For generating docs: start with well-defined OpenAPI schemas in YAML or JSON; plenty of tools (e.g., Docusaurus, ReadTheDocs, ReadMe.com) transform schemas into end-user and SDK docs
  • Discovery and purchasing: ensure APIs provide access to key decision data (e.g., model pricing), enabling LLMs to compare and recommend products/services based on structured API information

Closing Remarks 19:18

  • Sessions ends with thanks and brief outro music