Codex 3.0 by OpenAI

Codex can now build, test & debug on autopilot

5.0•24 reviews•

631 followers

Codex can now build, test & debug on autopilot

5.0•24 reviews•

631 followers

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AI Coding Agents

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Code Review Tools

With GPT-5.5, Codex evolves into a true cross-app coding agent—navigating browsers, interacting with web apps, generating docs in Microsoft Office and Google Drive, and testing workflows like a real user. It sees, clicks, debugs, and iterates autonomously, bringing developers closer to reliable, end-to-end automated builds.

Codex 3.0 by OpenAI Reviews

The community submitted 24 reviews to tell us what they like about Codex 3.0 by OpenAI, what Codex 3.0 by OpenAI can do better, and more.

5.0

Based on 24 reviews

Review Codex 3.0 by OpenAI?

Reviewers mostly praise Codex 3.0 for working from the actual codebase, handling multi-file tasks with more autonomy, and testing changes in a sandbox before returning them. One user says that makes it more trustworthy than tools that guess from prompts, though they also report slower runs, weak progress feedback, and some context loss on larger repos. Founders of MindPal, Velo, and GetThis similarly describe it as a practical tool for fast building, prototyping, debugging, and shipping.

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•25 reviews

What's great

It actually reads your codebase before doing anything. That sounds obvious but most AI coding tools just guess based on the prompt and hope for the best. Codex pulls in the real file structure, understands what's already there, and works with it instead of hallucinating functions that don't exist. The sandbox approach is smart too, you get a full environment so it can run and test its own changes before handing them back to you.

What needs improvement

slow performance (1)

Speed is the main thing. Tasks that feel like they should take 30 seconds sometimes take a few minutes while the sandbox spins up and runs. The UI could surface progress better too, sometimes you're just staring at a spinner not knowing if it's stuck or thinking. And the context window still has limits, on larger repos it can lose track of files it looked at earlier in the session.

vs Alternatives

Cursor

Claude Code

Been using Claude Code and Cursor heavily. Claude is great at reasoning through complex problems but it has a habit of assuming things about your code instead of checking. Cursor is fast for inline edits but less useful for multi-file tasks. Codex fills a different gap, it's the one I trust most to go off and do a chunk of work autonomously without coming back with code that references things that aren't there.

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4 views19d ago

used Codex 3.0 by OpenAI to build Stage

•1 review

Codex just felt closer to how I actually work. It handles bigger tasks, understands the repo better, and helps me move faster without constantly switching tools.

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1 view3d ago

used Codex 3.0 by OpenAI to build Ormedo

•3 reviews

Used for in the development of the product.

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6d ago

used Codex 3.0 by OpenAI to build Curlo

•2 reviews

Helped build the landing page and tutorials

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6d ago

used Codex 3.0 by OpenAI to build Tiny CV

•2 reviews

Just works for building software end to end

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1 view6d ago

used Codex 3.0 by OpenAI to build Growati

•3 reviews

Much better at building frontend.

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3d ago

used Codex 3.0 by OpenAI to build Integuru

•4 reviews

One of our go-to coding agents

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2d ago

used Codex 3.0 by OpenAI to build Novi Notes 1.1

•8 reviews

Novi doesn't lock you to one AI. Codex connects over MCP with no API keys and no cloud, so Codex users get the same local read/write access to their notes — and can switch AI anytime without losing their knowledge.

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1 view10d ago

used Codex 3.0 by OpenAI to build Slideshot

•13 reviews

I've been using the Codex macOS desktop app a lot recently, and it's fascinating to see how quickly the team at Open AI ships. The overall experience of using desktop app is so much better compared to CLI.

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10d ago

used Codex 3.0 by OpenAI to build DockFlow

•6 reviews

Codex, our every-purpose AI coding platform.

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1 view7d ago

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