Hasty Briefsbeta

The Bitter Lesson of LLM Extensions

2 hours ago
  • #Customization
  • #LLM Extensions
  • #AI Agents
  • The evolution of LLM extensions from simple text inputs to complex agents with customizable tools.
  • ChatGPT Plugins (March 2023) introduced the idea of LLMs using REST APIs, but models like GPT-3.5 struggled with API specs.
  • Custom Instructions (July 2023) simplified repetitive context setting by appending user-defined prompts to every chat.
  • Custom GPTs (November 2023) bundled personas, files, and actions into shareable links, moving towards single-purpose apps.
  • Memory in ChatGPT (February 2024) enabled automatic personalization by remembering user details across conversations.
  • Cursor Rules (April 2024) integrated custom instructions directly into code repositories via `.cursorrules` files.
  • Model Context Protocol (MCP) (November 2024) provided a robust framework for models to interact with tools and resources.
  • Claude Code (February 2025) introduced multiple extension mechanisms like `CLAUDE.md`, MCP, slash commands, and hooks.
  • Agent Skills (October 2025) simplified tool integration by using markdown files and scripts, reducing context bloat.
  • The future of LLM extensions may focus on natural language and general-purpose tools, moving away from specialized protocols like MCP.