January 2027
Intermediate
254 pages
6h 56m
English
Content preview from Claude Code: Up and Running
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
Chapter 8. Subagents, Agent Teams, and Plugins
Chapter 6 gave the agent repeatable workflows through skills. Chapter 7 connected it to live systems through MCP. Both still assume one agent in one session. Some tasks want more than that. A large review benefits from several distinct perspectives at once, and a single session cannot hold them all without its attention spreading thin.
One of my custom subagents is a Java test quality expert. It reviews a feature branch in the background, uses the SonarQube MCP server from Chapter 7, and reports whether one person can reasonably maintain the result. I created it through a conversation with Claude Code. Among the rules I added for the testing agent are “do not modify existing code until the tests have run”. The unexpected part was that I had to tell it to run the tests. You’d think telling it to write the tests would be enough, but that turns out not to be the case.
Subagents
A subagent is a specialized worker inside a single Claude Code session. To see why that matters, consider ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.