Act on this, mostly signal

Free open course rebuilds Claude Code style agent to teach harness engineering

What to do

Work through the course if you want to understand how harness choice changes agent results.

Why

It has eight articles and six videos that build a Claude Code style agent in Python. It cites LangChain's Terminal-Bench gain from 53 to 67 percent from the harness alone, and sponsors are named.

Read the source at news.ycombinator.com

What the research found

A free, open-source eight-article and six-video harness engineering course that builds a Claude Code-style agent in Python, citing LangChain's Terminal-Bench gain from 53% to 67% by changing only the harness; sponsored by Modal, Opik and Kitaru.

Claims and how well the evidence supports them

LangChain changed only the harness and its coding agent went from 53% to 67% on Terminal-Bench 96%
The course is free and open source with 8 articles, 6 videos and one codebase 99%
The course builds a Claude Code-style agent in Python 95%

Evidence

news.ycombinator.com https://news.ycombinator.com/item?id=50219641
github.com https://github.com/decodingai-magazine/building-a-coding-agent-from-scratch-course

Actionability rated low.