Field Notes, 127 Articles
Notes from the foundry
Engineering essays on generative AI, retrieval systems, and what it takes to ship intelligent software to production.
01Insights // DevelopmentWhy Trusting AI Generated Code Is the Wrong Goal2026-08-05→02AI EngineeringFive AI Agents, One Bug: When Missing Data Looks Like a Clean Result2026-08-05→03ComparisonsBest Open Weight LLMs for Agents in 20262026-08-04→04Tutorial // InfrastructureSelf-Hosted LLM Observability: Tracing Agents in Production with Langfuse2026-08-04→05Tutorial // AgentsWe Open-Sourced the AI Agent We Use to Scope Work and Watch Retainers2026-08-03→06Insights // TechnologyWhen Not to Build a Multi-Agent System2026-08-03→07Tutorial // SecuritySlopsquatting: How AI Hallucinated Packages Become a Supply Chain Attack2026-08-01→08Tutorial // SecurityAI Agent Security After the First Sandbox Escape2026-07-31→09Tutorial // MCPMCP Went Stateless: Migrating Your Server to the 2026-07-28 Spec2026-07-31→10Tutorial // DevToolsHow to Use Stacked Pull Requests on GitHub2026-07-31→11Tutorial // AgentsWe Open-Sourced an AI Agent for Coverage Citations: And Broke It Twice2026-07-30→12ComparisonsAI Agent Memory: Mem0 vs Zep vs Letta2026-07-29→13Insights // DevelopmentThe AI Coding Tools Stack: Why Teams Run Cursor, Claude Code, and Copilot Together2026-07-29→14Tutorial // Agentsagent-for-accounting: An Open-Source AI Agent for Bank-to-Ledger Reconciliation2026-07-28→15AI EngineeringAI Coding Agents in Large Codebases: Why Repository Intelligence Beats a Bigger Context Window2026-07-27→16ComparisonsClaude Opus 5 vs Grok 4.5 vs Muse Spark 1.1: Which Agentic Model to Use in 20262026-07-26→17AI EngineeringClaude Opus 5 Batch API Tutorial: AI Contract Data Extraction at Scale, with Real Costs2026-07-25→18AI EngineeringClaude Opus 5 Effort Parameter Guide: How to Reduce Claude API Costs Without Switching Models2026-07-25→19AI EngineeringHow to Build a Long-Running AI Agent with the Claude Opus 5 API: An Overnight Build Log2026-07-25→20AI EngineeringHow to Handle Claude Opus 5 Refusals in Production: stop_reason, stop_details, and the Fallbacks Parameter2026-07-25→