Wednesday, 18th March 2026
From Prompt Engineering to Harness Engineering: Building Infrastructure for Autonomous Agents
2025 was the year of agents. 2026 is the year of harnesses. A harness is the persistent infrastructure that gives a foundation model hands, feet, and senses. The shift is fundamental: from prompt engineering to harness engineering. Prompt engineering optimizes single interactions. Harness engineering builds the systems that control long-running, autonomous agents.
[... 1,179 words]7 Mental Models for Building Agent Skills (From Anthropic’s Internal Playbook)
Anthropic just published their internal playbook for Claude Code Skills. It draws on hundreds of skills in active use. Deep mental models for building better agents sit inside the practical advice. Here’s what they’re really telling you.
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