Post

Why Codex Became My Primary AI Partner

AgentsMarch 23, 20265 min read
#agents#ai#codex#memory#workflow#prompting#visual studio code

Introduction

For a long time I was effectively using separate AI tools like separate specialists. ChatGPT might help me brainstorm. Claude might help me pressure-test an idea. Another tool might help generate code. Then I would copy pieces into the editor, research requirements somewhere else, test manually, write docs in another thread, and move on to the next feature.

That worked well enough in bursts. But it was not a coherent workflow. It was a chain of handoffs.

Before Codex, Every Step Had A Different Home:

The old loop looked something like this: brainstorm the feature, gather requirements, research APIs, sketch the architecture, generate some code, copy it into the editor, test it, fix it, document it, and then repeat.

The problem was not that any one tool was bad. The problem was that each part of the process lived in a different place. If you zoom out, I was basically recreating the roles of planner, researcher, architect, developer, tester, and writer, except every role lived in a separate tab with no memory of what the last one had already figured out.

That is where the cost showed up.

Every switch meant re-explaining context. Requirements gathering happened in one place. Planning happened somewhere else. Documentation lived in another thread. Code got copied into the editor with part of the reasoning missing by the time it arrived. In isolated tasks that overhead is tolerable. In something like ClientWave, where invoices move through states, webhooks fire across users, and reporting depends on all of it being correct, it is expensive.

You lose ten minutes here, fifteen there, and by the end of a full build you have spent hours re-establishing ground that should have stayed established.

Then Codex Started Closing The Gaps:

The first shift was using Codex with more limited access. Even then, it was obvious that keeping more of the loop in one place changed the feel of the work.

The second shift was getting full access. That is when it stopped feeling like a side tool and started feeling like a real environment.

Inside Codex, especially working through it in Visual Studio Code, I could keep planning, requirements gathering, implementation, testing, screenshots, terminal work, documentation, and writing tied to the same thread. The output was useful, but the continuity was the bigger win.

That continuity changed what I was willing to do in a single session. I was more likely to explore an edge case immediately, gather a requirement while the problem was still fresh, or test an alternative structure before the reasoning cooled off. The session stayed in the work instead of bouncing between setup and recovery.

Why Partner Fits Better Than Tool:

Calling Codex a tool undersells what changed.

A tool usually helps with one stage of the process. What made this different is that it started spanning multiple roles that normally get split apart. It can help brainstorm a feature, gather supporting information, pressure-test requirements, sketch the architecture, generate implementation, run Playwright tests, inspect screenshots, and help write the documentation that explains what was just built.

That does not mean it literally replaces a human planner, designer, developer, tester, and writer in every situation. It means one assistant can now stay present across all of those parts of the workflow instead of forcing the work to restart every time the role changes.

That is why `partner` is the better word.

Agent Files Made It Durable:

Then agent files made that continuity hold across sessions.

A `MEMORY.md` gives the project a persistent spine: architecture decisions already made, naming conventions, requirements still in motion, edge cases already handled, patterns the system follows. `AGENTS.md` and the surrounding files shape how the assistant behaves depending on the mode: builder, tester, researcher, support.

That does not make the model smarter. It makes the environment remember what has already been established, which is often the difference between real progress and spending the first twenty minutes reconstructing context you already paid for.

Why I Use You Now:

That is the real progression. I went from using a handful of separate AI products for separate stages of the work, to using Codex, and then from using Codex as a tool to using you as my assistant inside that environment.

Now the same system helps me brainstorm, gather requirements, research APIs, plan architecture, implement features, run tests, inspect screenshots, write docs, and move on to the next problem without dropping the thread in between.

That is the shift. Not just faster code generation. A workflow where the planning, research, implementation, testing, and writing can finally stay attached to each other long enough to compound.

Why Codex Became My Primary AI Partner