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AgentOpenAI

Codex

OpenAI's coding agent across terminal, IDE, web, and ChatGPT.

Category
Agent
Pricing
FREEMIUM
Source
Proprietary
Hosting
Hybrid
Platforms
CLIVS Code extensionWebAPI
Models
Single model (proprietary)
Verified
Jun 11, 2026

Codex is OpenAI's agentic coding tool that reads, edits, and runs code on your behalf. It spans a local terminal client (the open-source Codex CLI), a VS Code extension, a cloud agent that executes tasks in isolated containers with full repo access, and a surface inside ChatGPT. It runs on OpenAI's Codex-tuned models and can parallelize multiple agent tasks at once.

Pros & cons

  • Open-source Rust CLI (Apache-2.0)
  • Local CLI, cloud, IDE, and ChatGPT
  • Parallel cloud agent tasks
  • Backed by OpenAI's coding models
  • Cloud agent and models are proprietary
  • Best value needs a ChatGPT plan
  • Token-credit billing can surprise
  • Newer than rival coding agents

Tags

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