OpenAI: GPT-5 Codex for Developers

Optimize your coding workflow with GPT-5 Codex's advanced features.

Input: text · image Output: text Context: 400,000 tokens Release: 2025-09-23

OpenAI's GPT-5 Codex, released in September 2025, is tailored for software engineering and coding workflows. It features a substantial context window of 400,000 tokens and supports both text and image inputs, producing text outputs. Codex excels in interactive development, debugging, and code reviews, adapting to tasks of varying complexity. It integrates seamlessly with developer tools like IDEs and CLI, offering dynamic reasoning effort for efficient task handling. With capabilities for multimodal inputs and tool integration, Codex is designed to enhance agentic coding applications.

Use Cases

Here are a few ways teams apply OpenAI: GPT-5 Codex in practice—from fast drafting to multimodal understanding. Adapt these ideas to your workflow.

Develop projects from scratch

Conduct thorough code reviews

Debug complex software issues

Refactor large codebases efficiently

Integrate multimodal inputs for UI tasks

Key Features

A quick look at the capabilities that make this model useful in real projects.

Optimized for software engineering tasks

Supports text and image inputs

Produces high-quality code outputs

Dynamic reasoning effort adjustment

Integrates with IDEs and CLI tools

Specs

Overview

Vendor
openai

Model ID
openai/gpt-5-codex

Release
2025-09-23

Modalities & context

Input
text · image

Output
text

Context
400,000 tokens

Parameters & defaults

Supported parameters: include_reasoning, max_tokens, reasoning, response_format, seed, structured_outputs, tool_choice, tools

Defaults: temperature 0.2, top_p 0.95

Benchmark tests: OpenAI: GPT-5 Codex

We ran this model against a few representative prompts to show its range. Review the outputs below and be the judge.

Text

Prompt:

Write 150 words on how AI might positively upend work, leisure and creativity

Artificial intelligence is poised to reinvent how we earn a living, turning workplaces into ecosystems where human intention directs algorithmic muscle. Predictive copilots could shoulder repetitive tasks, freeing professionals to experiment with strategy, mentorship, and ethical stewardship, while dynamic reskilling platforms keep careers fluid instead of fragile. Leisure likewise stands to evolve, as personalized agents manage chores, curate restorative micro-retreats, and even choreograph social gatherings, making downtime expansive rather than escapist. Creative practice may benefit most profoundly: generative models already remix modalities, allowing designers, musicians, and writers to prototype bold ideas instantly, iterate with machine feedback, and collaborate across languages or disciplines. Instead of replacing imagination, AI can widen the sandbox, surfacing unexpected patterns that invite human judgment and emotion. By aligning these tools with transparent governance and inclusive access, societies can celebrate a future where work sustains purpose, leisure nourishes wellbeing, and creativity becomes a shared civic commons together.

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Image

Prompt:

Generate an SVG of a pelican riding a bicycle.

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up.end

/ˌəpˈend/

verb

To “upend” means to completely disrupt, overturn, or drastically change the established order or structure of something. It implies a significant shift or alteration that can potentially have far-reaching consequences. When something is upended, it is turned upside down or transformed in a way that challenges conventional norms or expectations. The term often carries a sense of innovation, transformation, and sometimes even a hint of upheaval, indicating that the changes are not just minor adjustments but rather a fundamental reimagining of the status quo.

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