---
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id: "9d4b9e1fe5ab58191ec5f3a0ed8384ef87dc36aa1d49b09fcdafe7188a3d87cf"
canonical_url: "https://aidr.today/9d4b9e1f?lang=en"
title: "Harness Engineering 101: The LLM is the brain, the harness is the body"
lang: "en"
requested_lang: "en"
available_langs: ["en","vi"]
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published_at: "2026-10-19T12:07:41.000Z"
category: "Open Source"
topics: ["agent","open-source"]
source_urls: ["https://github.com/IsuruMaduranga/harness-engineering-101","https://news.ycombinator.com/item?id=50151390"]
summary: "A guide called Harness Engineering 101 explains how to build AI agents from first principles, describing the LLM as the brain and the harness as the body."
---

# Harness Engineering 101: The LLM is the brain, the harness is the body

> [Open the canonical story](<https://aidr.today/9d4b9e1f?lang=en>)

**Published:** 2026-10-19T12:07:41.000Z
**Category:** Open Source
**Topics:** agent, open\-source

## Summary

A guide called Harness Engineering 101 explains how to build AI agents from first principles, describing the LLM as the brain and the harness as the body\.

## Sources

- [Story source](<https://github.com/IsuruMaduranga/harness-engineering-101>)
- [Discussion](<https://news.ycombinator.com/item?id=50151390>)