Retour aux articles
Monday, September 28, 20267 vues0

Codex’s comeback against Claude Code: why the balance shifted

Mike Codeur

IA
Claude Code
Agents

Codex’s comeback against Claude Code

▶️ Watch the full video

2026 was Claude Code’s year. Anthropic’s tool became the default for many developers because it offered more than a capable model: it provided a coherent environment for navigating a repository, using the terminal, calling tools and pushing work through verification.

Then the balance started to shift.

Some developers grew frustrated with restrictions, third-party usage limits and friction around headless workflows. At the same time, OpenAI stopped treating Codex as an isolated coding agent and rebuilt it as a complete working platform.

Why Claude Code moved ahead

OpenAI already had strong models and ChatGPT’s distribution, but its developer experience remained fragmented.

Anthropic had assembled the pieces required for agentic work:

  • repository context;
  • terminal and tool access;
  • a continuous execution loop;
  • permissions and approvals;
  • task delegation;
  • an interface designed for developers.

A model alone does not ship verified code. The agent must understand the project, edit the right files, run tests, inspect failures and iterate until the result works.

Claude Code built that product advantage before Codex.

How OpenAI rebuilt Codex

The comeback did not come from one benchmark or one model release. OpenAI rebuilt the environment around the model.

Codex now spans the CLI, IDE, cloud, desktop, mobile and SSH. It connects context, tools, permissions, memory and parallel agents inside one system.

That changes the daily workflow. Tasks can be delegated while the main agent remains available. Implementation, testing and review can progress in parallel before their results converge.

In my own work, the difference is practical:

  • less waiting during delegation;
  • fewer manual restarts;
  • shorter implementation, review and correction loops;
  • clearer test and execution evidence.

This is not a controlled benchmark. My projects are real, but the tasks are not identical. What I can measure honestly is how often each product interrupts my work.

Benchmarks do not produce a universal winner

An external benchmark discussed in the video shows why simplistic rankings are misleading.

MetricClaude CodeCodex
Golden Eval workflows completed47/4745/47
Speed in this protocolBaselineAbout 6% faster
Token usageBaselineAbout 19% lower
DeepSWE cost at equal success$9.18$3.47

In that protocol, Claude wins on raw reliability while Codex wins on efficiency. The winner depends on whether you optimize for completion rate, time, tokens, cost or everyday workflow fluidity.

Where Claude Code still leads

Codex is now my default for targeted fixes, parallel features and short feedback loops. I still choose Claude Code for specific jobs.

For audits across hundreds of files, large migrations and long multi-agent runs, Claude’s Dynamic Workflows can organize the stages, resume the process and have other agents verify the output.

I also prefer Claude for Remote Control and reconnection after interruptions. In my experience, its continuity between terminal, browser and phone remains more reliable.

MissionMy current choice
Targeted fixCodex
Parallel feature workCodex
Implementation, review and test loopCodex
Large auditClaude Code
Large migrationClaude Code
Dynamic WorkflowsClaude Code
Mobile control and reconnectionClaude Code

Keep a method that survives the next leader

The leader will change again. I therefore keep the same foundation with both products: user stories, acceptance criteria, TDD, separate review, tests and final evidence.

That method lets me change tools without rebuilding the whole process. Codex is my default today, while Claude Code remains better for several large or long-running missions.

▶️ Watch the full Codex comeback analysis

For more practical notes about AI agents and agentic development, join The Agentic Dev.

Rejoins The Agentic Dev

Chaque semaine : outils, workflows et stratégies pour coder avec les agents IA comme un pro.

Workflows agentic testés en prod
Outils IA qui marchent vraiment
+35 000 développeurs déjà inscrits

Gratuit · 1 email / semaine · +1250€ de formations offertes