OpenAI
OpenAI's coding agent — debugging, reviewing, deploying, not just writing the function.
400K tokens
Contexto
128,000 tokens
Saída máxima
Médio
Velocidade
Whole tasks across the lifecycle, not one snippet.
Reads real failures and works towards the cause.
Reviews a change against the intent behind it.
Takes images, so a broken UI can go in directly.
Tuned to this model — click any line to copy.
GPT-5.3 Codex is OpenAI's coding specialist, announced on 5 February 2026. It combines the coding strength of the Codex line with the general reasoning and professional knowledge of the wider GPT-5 series, and OpenAI's framing of it is deliberately broad: Codex moves from an agent that writes and reviews code to an agent that can do most of what a developer does on a computer.
That shows up in what it is tuned for. Debugging, deploying, monitoring, writing specs, editing copy, tests and metrics are all in scope, not just producing a function on request. It sets high marks on the benchmarks that measure real repository work rather than puzzle-solving — SWE-Bench Pro and Terminal-Bench in particular — and OpenAI reports it runs roughly 25% faster than GPT-5.2 Codex, which matters more than it sounds when a model is doing dozens of steps in a row.
It exposes adjustable reasoning effort, so the same model can answer quickly or think hard depending on what the task deserves, and it takes images as input, so a screenshot of a broken build or an unreadable chart can go straight into the thread. The context window runs to about 400K tokens with up to 128K tokens of output, enough to hold a large slice of a repository plus a long agent transcript.
On NinjaChat it is included in every plan. Pick it from the model list when the work is software, and switch to a general model when it is not.
Do zero ao seu primeiro resultado em menos de um minuto.
01
Create a NinjaChat account and choose a plan
02
Open chat and pick GPT-5.3 Codex from the model list
03
Give it the repository context, the failure and the goal
04
Ask for a plan first on anything that spans files
Comparações honestas — onde o {model} vence e onde não vence.
OpenAI's reasoning-effort control and wider tooling
Kimi K2.7 Code is open-weights and cheaper per token
Tuned specifically for software and agent runs
Terra is the better all-round generalist
Todo plano NinjaChat inclui 50+ modelos, um estúdio completo de imagens e geração de vídeo.



Uma única assinatura cobre todos os modelos do NinjaChat, incluindo GPT-5.3 Codex.