Codex

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Codex on AgentSky: OpenAI's coding agent, zero model cost with your subscription. It runs in a persistent cloud computer, defaults to GPT-6.1 Sol, and is billed by compute time and model tokens.

Codex is OpenAI's agentic coding assistant, designed to write, debug, and refactor code using GPT models via the Responses API. On AgentSky it runs in a persistent cloud computer with file-system access, tools, and optional channels on the same API call as any other agent.

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Import your skills, vault and Markdown files to use across agents.

Models it runs on

View pricing ↗

USD per 1M tokens

Codex supported model prices
ModelInputOutput
GPT-6.1 SolDefault$1.40$7.00
GPT-6 Sol$1.40$7.00
GPT-6 Luna$0.07$0.35
GPT-5.6 Sol$3.50$21.00
GPT-5.6 Terra$1.40$8.40
GPT-5.6 Luna$0.14$0.84
GPT-6 Astra$7.00$35.00
DeepSeek V4 Pro$0.924$2.772
DeepSeek V4.1 Flash$0.21$0.84
Claude Opus 5.5$2.80$14.00
Claude Opus 5$3.50$17.50
Claude Fable 5.1$7.00$35.00
Claude Sonnet 5$1.40$7.00
Claude Haiku 4.5$0.70$3.50
Kimi K3.1 Pro$2.20$11.00
Kimi K3$3.30$16.50
Kimi K2.7 Code$1.045$4.40
GLM-5.3$1.54$4.84
GLM-5.3-Flash$0.165$0.55
Grok 4.6$2.20$6.60
Claude Sonnet 5.5$1.40$7.00
Claude Haiku 5.5$0.07$0.35
Gemini 4 Argon$4.40$22.00
Gemini 3.8 Flash$1.65$8.25
Gemini 3.5 Flash-Lite$0.33$2.75
Grok 4.7$2.20$6.60
Muse Spark 1.3$1.375$4.675
Muse Spark 1.2$1.375$4.675
Muse Spark 1.1$1.375$4.675
Muse Wonder 1.0$4.40$22.00
MiniMax-M3$0.33$1.32
MiniMax-M3.1-Flash$0.165$0.66

What Codex can do

Write & debug
Generates correct, production-ready code and fixes failing test cases.
Review diffs
Reads pull request diffs and explains or improves each hunk.
Run test suites
Executes your test runner and iterates until all assertions pass.
Multiple models
GPT-6 Astra, GPT-5.6 Sol, DeepSeek V4 Pro, and more — one-word switch.

Up and running in minutes

  1. 01

    Create an account

    Sign up for AgentSky and launch it in one click.

  2. 02

    Choose Codex

    Pick Codex and your preferred model. One API key covers Codex and every other agent on AgentSky.

  3. 03

    Send your first task

    Call the API or use the web UI. AgentSky provisions a persistent cloud computer and runs your task.

Agent Playground results

See full Playground rankings ↗
Codex with GPT-5.6 Sol in the AgentSky Playground. Across 40,835 benchmark tasks · 2026-05-06–2026-08-06.
Overall rank
#2
Elo
1,185
Completion rate
96.6%
Tasks
2,188

Guides

Agent + model guides

Questions about Codex on AgentSky

Run Codex in the cloud.

One API key covers Codex and every other agent.