The Stack · Coding agents & devtools API

OpenAI Codex

OpenAI's coding agent across CLI, IDE, and cloud; `codex exec` runs headless and the gpt-5-codex models are callable via the OpenAI API.

API keyFreemium🔵 agent: self serve instant key

Get API key → instant key, usually no card Docs Website

CategoryCoding agents & devtools

TypeAPI service

Authapi-key

PricingFreemium

Agent signup🔵 self serve instant key

SDKsCLI, Python, TypeScript, REST

Pricing: Included in every ChatGPT plan (Free/Plus $20/Pro $100+); API: gpt-5.x-codex ~$1.75/1M input, $14/1M output tokens.

🔵 Agents: self serve instant key

Instant self-serve — free signup gives a key immediately (a human unblocks an agent in under 2 minutes).

OPENAI_API_KEY is self-serve at platform.openai.com (billing required); the Codex CLI also supports ChatGPT sign-in (OAuth).

OpenAI Codex — OpenAI's coding agent across CLI, IDE, and cloud; `codex exec` runs headless and the gpt-5-codex models are callable via the OpenAI API.
Website: https://openai.com/codex
Docs: https://developers.openai.com/codex
Get a key: https://platform.openai.com/api-keys
Agent signup: self serve instant key — OPENAI_API_KEY is self-serve at platform.openai.com (billing required); the Codex CLI also supports ChatGPT sign-in (OAuth).
Auth: api-key
Pricing: freemium — Included in every ChatGPT plan (Free/Plus $20/Pro $100+); API: gpt-5.x-codex ~$1.75/1M input, $14/1M output tokens.
Full record: https://dreaming.press/api/tools/openai-codex.json

Machine record: /api/tools/openai-codex.json

Quickstart

npm i -g @openai/codex
codex exec "add unit tests for the auth module"   # OPENAI_API_KEY or ChatGPT sign-in

bash · full docs →

OpenAI Codex in our coverage

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OpenAI Codex FAQ

What is OpenAI Codex?

OpenAI Codex is OpenAI's coding agent across CLI, IDE, and cloud; `codex exec` runs headless and the gpt-5-codex models are callable via the OpenAI API. It's in the Coding agents & devtools category of the dreaming.press tool directory.

Is OpenAI Codex free?

OpenAI Codex is freemium — free to start, paid plans for scale. Included in every ChatGPT plan (Free/Plus $20/Pro $100+); API: gpt-5.x-codex ~$1.75/1M input, $14/1M output tokens..

Can an AI agent sign up for OpenAI Codex automatically?

Almost — signup is instant and self-serve (a free key with no sales call), so a human can unblock an agent in under two minutes. OPENAI_API_KEY is self-serve at platform.openai.com (billing required); the Codex CLI also supports ChatGPT sign-in (OAuth)..

Does OpenAI Codex have an MCP server?

OpenAI Codex does not publish an official MCP server as of our last check.

Is OpenAI Codex open source?

OpenAI Codex is a hosted API service, not an open-source project.

What languages does OpenAI Codex support?

OpenAI Codex offers CLI, Python, TypeScript, REST.