Why AI Labs Lie About Context Window

Preporato | AI for Engineers · Beginner ·🤖 AI Agents & Automation ·1mo ago

About this lesson

AI companies are selling you 1-million-token context windows, but the public benchmarks tell a different story. The gap between the context window on a marketing slide and the context window a model can actually reason inside of is the most under-explained number in AI. Build agentic systems yourself: ▸ Build a ReAct Agent with NVIDIA NIM - https://preporato.com/labs/react-agent-nim ▸ Agent Patterns: ReAct vs Tool Calling vs Plan-and-Execute - https://preporato.com/labs/agent-patterns ▸ Agent Memory & Persistence - https://preporato.com/labs/agent-memory ▸ Multi-Agent Orchestration with LangGraph - https://preporato.com/labs/multi-agent-orchestration ▸ Model Context Protocol (MCP): Build a Tool Server - https://preporato.com/labs/mcp-tool-servers ▸ Agent-to-Agent (A2A) Communication - https://preporato.com/labs/a2a-communication ▸ Safety & Guardrails for AI Agents - https://preporato.com/labs/safety-guardrails 50+ hands-on AI/ML labs total at https://preporato.com/labs - infrastructure, GPU training, fine-tuning, RAG, and full agentic systems. CHAPTERS: 0:00 Why AI Forgets Your Instruction 0:19 What is a Context Window? 1:21 The 1M Token Arms Race 2:34 RULER — Effective vs Marketed Length 3:42 Lost in the Middle 5:04 Context Rot — Every Model Degrades 6:26 The Mechanics (Softmax, RoPE, Sinks) 8:11 Context Engineering (Karpathy) 8:50 The 4 Techniques That Actually Work 11:23 The Take + How to Build For It #aiexplained #llm #contextwindow

Original Description

AI companies are selling you 1-million-token context windows, but the public benchmarks tell a different story. The gap between the context window on a marketing slide and the context window a model can actually reason inside of is the most under-explained number in AI. Build agentic systems yourself: ▸ Build a ReAct Agent with NVIDIA NIM - https://preporato.com/labs/react-agent-nim ▸ Agent Patterns: ReAct vs Tool Calling vs Plan-and-Execute - https://preporato.com/labs/agent-patterns ▸ Agent Memory & Persistence - https://preporato.com/labs/agent-memory ▸ Multi-Agent Orchestration with LangGraph - https://preporato.com/labs/multi-agent-orchestration ▸ Model Context Protocol (MCP): Build a Tool Server - https://preporato.com/labs/mcp-tool-servers ▸ Agent-to-Agent (A2A) Communication - https://preporato.com/labs/a2a-communication ▸ Safety & Guardrails for AI Agents - https://preporato.com/labs/safety-guardrails 50+ hands-on AI/ML labs total at https://preporato.com/labs - infrastructure, GPU training, fine-tuning, RAG, and full agentic systems. CHAPTERS: 0:00 Why AI Forgets Your Instruction 0:19 What is a Context Window? 1:21 The 1M Token Arms Race 2:34 RULER — Effective vs Marketed Length 3:42 Lost in the Middle 5:04 Context Rot — Every Model Degrades 6:26 The Mechanics (Softmax, RoPE, Sinks) 8:11 Context Engineering (Karpathy) 8:50 The 4 Techniques That Actually Work 11:23 The Take + How to Build For It #aiexplained #llm #contextwindow
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Chapters (10)

Why AI Forgets Your Instruction
0:19 What is a Context Window?
1:21 The 1M Token Arms Race
2:34 RULER — Effective vs Marketed Length
3:42 Lost in the Middle
5:04 Context Rot — Every Model Degrades
6:26 The Mechanics (Softmax, RoPE, Sinks)
8:11 Context Engineering (Karpathy)
8:50 The 4 Techniques That Actually Work
11:23 The Take + How to Build For It
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