# Claude Code vs Codex CLI: Terminal Agents Compared (2026)

> Claude Code vs OpenAI's Codex CLI — autonomy vs sandboxed control, extensibility vs open source, model ecosystems, and which terminal agent fits your work.

Both are first-party terminal agents; the split is philosophy. Claude Code optimizes for capable autonomy — deep agentic loop, MCP/subagents/hooks/skills, Anthropic's models, permissions as the guardrail. Codex CLI optimizes for contained execution — OS-level sandbox modes and approval policies, open-source Rust, OpenAI's models. Trust posture and model allegiance decide it.

The two first-party terminal agents — Anthropic's **Claude Code** and OpenAI's **Codex CLI** — look interchangeable from a distance: run a command in a repo, describe a task, review the diff. Up close they encode different philosophies about what makes an agent trustworthy: Claude Code bets on *programmable governance*, Codex CLI bets on *contained execution*.

## The short answer

- **You want maximum agentic depth and a programmable harness** (MCP, subagents, hooks, skills, CI) → **Claude Code**.
- **You want OS-level containment by default and an open-source agent** → **Codex CLI**.
- **You've already standardized on one provider's models** → follow the provider; both agents are tuned for their own.

## Philosophy, made concrete

**Codex CLI's signature is the two-layer security model.** Sandbox modes (`read-only`, `workspace-write`, `danger-full-access`) define what's *technically possible* — default: writes scoped to the workspace, no network. Approval policies (`on-request`, `untrusted`, `never`) define when it must *ask*. It's Rust, Apache-2.0, with headless `codex exec` for CI, model switching with reasoning-effort control, and a deliberate workflow stance: it doesn't auto-commit — staging and committing stay yours. It reads `AGENTS.md` for project context. [Tool profile →](/tools/codex-cli)

**Claude Code's signature is the programmable harness.** The agentic loop runs deep — plan, edit, run tests, iterate, open the PR — and everything around it is extension surface: [MCP servers](/guides/mcp/claude-code-mcp-setup) for reach, [subagents](/guides/getting-started/getting-started-with-agents) for delegation, [hooks](/guides/configuration/claude-code-hooks) for deterministic rules, skills and plugins for packaged workflows, [permission rules and modes](/guides/configuration/claude-code-settings-permissions) for policy. Containment is governed rather than sandboxed-by-default (sandboxing options exist; the default trust model is the permission layer). It's git-native and reads `CLAUDE.md`. [Tool profile →](/tools/claude-code)

## Dimension by dimension

| | Claude Code | Codex CLI |
| --- | --- | --- |
| Safety model | Permissions, modes, hooks (policy layer) | OS sandbox × approval policies (containment) |
| Source | First-party, not OSS | Open source (Apache-2.0, Rust) |
| Models | Anthropic, deeply tuned | OpenAI, switchable tiers |
| Extensibility | MCP + subagents + hooks + skills + plugins | MCP + config customization |
| Git stance | Stages/commits/opens PRs on request | Leaves committing to you |
| Project context | CLAUDE.md (+ rules, memory) | AGENTS.md |
| Headless/CI | claude -p + GitHub Action + Agent SDK | codex exec |

## How to actually choose

For most teams this decision is downstream of two prior bets. **The model bet:** both agents are conspicuously better with their own provider's models; if your org runs on Claude or on OpenAI, the agent follows. **The trust bet:** if your nightmare is an agent touching what it shouldn't on *unfamiliar* code, Codex's sandbox-by-default is the comfortable posture; if your goal is encoding *team* policy — these commands always allowed, these paths never touched, this approval always required — Claude Code's permission-and-hooks layer is the deeper instrument.

And if the real requirement is model freedom — any provider, local models included — neither is the answer: that's [OpenCode's comparison](/guides/comparisons/claude-code-vs-opencode) and the broader [open-source CLI field](/guides/prompting/ai-coding-agents-cli-2026).

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_Source: https://agentscamp.com/guides/comparisons/claude-code-vs-codex-cli — Guide on AgentsCamp._