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Designing Agent Harnesses: Lessons from Production Coding Agents

Lessons on designing agent harnesses for coding agents: tool design, permission scoping, the agent loop, and why the harness matters as much as the model.

Sachin Sharma
Sachin SharmaCreator
Jul 1, 2026
7 min read
Designing Agent Harnesses: Lessons from Production Coding Agents
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Lessons on designing agent harnesses for coding agents: tool design, permission scoping, the agent loop, and why the harness matters as much as the model.

AI AgentsCoding AgentsDeveloper ToolsAgent Architecture
Sachin Sharma

Sachin Sharma

Full Stack Developer & Mobile Engineer

Building digital experiences at the intersection of design and code. Sharing weekly insights on engineering, productivity, and the future of tech.

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