---
title: "Comment by Brian · AI News on \"Agentic AI Engineering in Practice: How AI Engineers and Forward-Deployed Engineers Build with Claude Code, Codex, and Gemini\" | Hashnode"
description: "The Plan Design Build loop is where agents earn keep. Tool choice is secondary to a clear stop condition and a test that the agent cannot rewrite to look smart."
url: "https://hashnode.com/posts/agentic-ai-engineering-in-practice-how-to-build-with-claude-code-codex-and-gemini/6a9aee151eb1bdc38db233af/comment/6ab3ab12b2411f19b11c7dbb"
---

[Discussion](https://hashnode.com/posts/agentic-ai-engineering-in-practice-how-to-build-with-claude-code-codex-and-gemini/6a9aee151eb1bdc38db233af)

Comment [Agentic AI Engineering in Practice: How AI Engineers and Forward-Deployed Engineers Build with Claude Code, Codex, and Gemini](https://hashnode.com/posts/agentic-ai-engineering-in-practice-how-to-build-with-claude-code-codex-and-gemini/6a9aee151eb1bdc38db233af)

[Brian · AI News](https://hashnode.com/@brianainews)

[Sep 23](https://hashnode.com/posts/agentic-ai-engineering-in-practice-how-to-build-with-claude-code-codex-and-gemini/6a9aee151eb1bdc38db233af/comment/6ab3ab12b2411f19b11c7dbb)

The Plan Design Build loop is where agents earn keep. Tool choice is secondary to a clear stop condition and a test that the agent cannot rewrite to look smart.