Catalog Systems Agent IDEs & coding harnesses ChatGPT — Codex (cloud agent)

ChatGPT — Codex (cloud agent)

https://chatgpt.com/codex

OpenAI's cloud-hosted, asynchronous coding agent surfaced inside ChatGPT — distinct from Codex CLI (terminal) and from the deprecated 2021 Codex API. Released 2025-05. Reads + writes from sandboxed cloud environments; integrates with GitHub. Cross-listing — the coding-agent-memory row remains canonical for memory framing.

Active · Verified 2026-10-26 · fresh as of 2026-10-26 · 58 cited facts, 2 with a third-party source · 1 recorded change · Suggest a correction

At a glance

Type
OpenAI's ChatGPT-integrated cloud coding agent vendor fix
Tier
T1
Section
Agent IDEs & coding harnesses
Created
2025-05 vendor fix
Latest release
not applicable — not OSS fix
License
not applicable — not OSS fix
GitHub
not applicable — no GitHub repo fix
Pricing
Included in ChatGPT plans (Free/Go limited, Plus $20/mo, Pro $100–200/mo, Business $25/user/mo); usage metered in credits per model tokens third-party fix
Funding
OpenAI (parent) vendor fix
Freshness
2026-10-26 fix
Layer
agent-infra repo fix
Licensing
commercial third-party fix
Deployment locus
cloud vendor fix
Platform vs product
product vendor fix

When to use

Optimised for: asynchronous cloud coding tasks from ChatGPT

Anti-fit: no terminal UX (Codex CLI is the separate product); OpenAI-only

Pros & cons

Pros

Massive distribution via the ChatGPT install base; cloud sandbox lets non-power-users run agents without setting up local tooling.

Cons

ChatGPT-only; cloud-only (no local code access); pricing only via ChatGPT subscription, not per-task.

Claims & capabilities

OpenAI; launched 2025-05; bundled with ChatGPT Plus/Pro; SWE-bench-Verified numbers shipped with launch.

Technical surface

API surface
ChatGPT web/app + API (Codex tasks)
Backend storage
cloud sandbox per task
Deployment
Managed-only — OpenAI-hosted sandboxed cloud environments, via ChatGPT web/app (chatgpt.com/codex), IDE extension and CLI
Embedding model
not applicable — not a memory product
Multi-tenancy
per-user (ChatGPT account)
MCP
searched not found
A2A
searched not found
OpenTelemetry
searched not found

Alternatives to ChatGPT — Codex (cloud agent) → live options ranked by shared design, licence, hosting and MCP support

Similar systems

Other agent ides & coding harnesses in the catalog, ranked by inbound references.

  • Claude Code (Anthropic) T1

    Anthropic's agentic coding tool: Claude as a coding agent in the terminal, IDEs (VS Code, JetBrains), desktop app, web/mobile, GitHub and Slack. Context via CLAUDE.md, skills, hooks, subagents and MCP servers.

  • Cursor (IDE) T1

    AI-first IDE that forked VS Code; Composer (multi-file edit) and Agent Mode (long-running coding agent) are its flagship surfaces. Memory layer = .cursorrules / Rules; recall via repo-aware Context Engine. Anysphere (parent) raised $900M Series C at $9.9B in May 2025; acquired by SpaceX (announced 2026-08-14, terms undisclosed), product continues under the Cursor brand.

  • OpenAI Codex CLI T1

    OpenAI's actively developed OSS terminal coding agent (Apr 2025), now written in Rust (codex-rs replaced the original TS CLI); also IDE extension + desktop app. Separate from the Codex Web cloud agent and the retired 2021 Codex model API. The codex mcp-server command (Codex as an MCP server) was deprecated on 2026-08-24 and removed in CLI 0.154.0 (2026-09-09); OpenAI points integrations to the experimental Codex app server, and codex mcp still connects Codex to external MCP servers.

  • Opencode (SST) T2

    SST team's open-source terminal coding agent — TypeScript, multi-model, MCP-native. Released 2025; explicitly positioned as a permissively-licensed Claude Code alternative. Memory via AGENTS.md (the emerging cross-harness convention).

  • Bedrock AgentCore (AWS) T2

    AWS Bedrock AgentCore — managed runtime to deploy + scale + observe agents. Multi-component: Runtime, Identity, Memory, Gateway, Browser, Code Interpreter, Observability. Distinct from Bedrock Agents (older fixed-config product); AgentCore is the 2025 framework-agnostic runtime for any agent (LangGraph, CrewAI, Strands, OpenAI Agents SDK).

  • GitHub Copilot (Agent Mode) T1

    The original AI coding assistant (Copilot in editor; 2021). 2025 evolved into a full agentic surface: chat, completions, Agent Mode (multi-step), and Copilot Workspace. Backed by Microsoft. Distinct row from Workspace — this row covers the everyday in-editor + agent mode product, Workspace covers the hosted spec-driven workflow.

Sources (57 cited facts, 2 third-party)

Each fact links to the page it came from; the badge says who published it (how to read sources).

What changed

Changes to this record's lifecycle, licence, release, pricing and hosting facts, from the catalog's git history. Subscribe (Atom)

  1. 2026-10-26
    • Pricing “Bundled with ChatGPT Plus ($20/mo) + Pro ($200/mo)” → “Included in ChatGPT plans (Free/Go limited, Plus $20/mo, Pro $100–200/mo, Business $25/user/mo); usage metered in credits per model tokens” source
    • Deployment “Cloud” → “Managed-only — OpenAI-hosted sandboxed cloud environments, via ChatGPT web/app (chatgpt.com/codex), IDE extension and CLI” source
    #258

Related systems

References (2)