# GitHub Copilot CLI vs OpenAI Codex

> OpenAI Codex has a score of 73.4 (BB) against GitHub Copilot CLI's 57.9 (C). Both do agent harness. The largest gap is security & auth, 22 points. Category scores, facts, verdicts and agent notes side by side.

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- Updated: 2026-10-05

OpenAI Codex has a score of 73.4 (BB) against GitHub Copilot CLI's 57.9 (C). Both do agent harness. The largest gap is security & auth, 22 points.

- GitHub Copilot CLI: grade C, 57.9/100, rank #286 of 452. Markdown https://www.anchorterminal.com/tools/github-copilot-cli.md · JSON https://www.anchorterminal.com/api/v1/tools/github-copilot-cli.json
- OpenAI Codex: grade BB, 73.4/100, rank #58 of 452. Markdown https://www.anchorterminal.com/tools/openai-codex.md · JSON https://www.anchorterminal.com/api/v1/tools/openai-codex.json

## Which one, for what

Pick GitHub Copilot CLI for nothing in particular (no category where it leads by five points or more).

Pick OpenAI Codex for schema & documentation (+18), agent ergonomics (+8), security & auth (+22), payments & pricing (+20), maintenance & community (+10), transparency & trust (+11).

## Score by category

| Category | Weight | GitHub Copilot CLI | OpenAI Codex | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 55 | 55 | even |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 72 | 90 | OpenAI Codex +18 |
| Agent ergonomics | 13% (16.2 this run) | 72 | 80 | OpenAI Codex +8 |
| Security & auth | 14% (17.5 this run) | 60 | 82 | OpenAI Codex +22 |
| Payments & pricing | 10% (12.5 this run) | 40 | 60 | OpenAI Codex +20 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 77 | 87 | OpenAI Codex +10 |
| Transparency & trust | 7% (8.8 this run) | 72 | 83 | OpenAI Codex +11 |
| Negative events | ≤15 | -5 | -2 | |
| **Total** | | **57.9 · C** | **73.4 · BB** | |

## Facts side by side

| Fact | GitHub Copilot CLI | OpenAI Codex |
| --- | --- | --- |
| Kind | Agent harness | Agent harness |
| Vendor | GitHub | OpenAI |
| Hosted endpoint | no (local only) | no (local only) |
| Transports |  |  |
| Auth | OAuth or key | OAuth or key |
| Pricing | Freemium | Freemium |
| x402 | no | no |
| Licence | Proprietary, under the licence in the repository's `LICENSE.md`. Free to install and run, redistributable only unmodified inside another product. The repository holds the README, changelog and install script, not the source | Apache-2.0 (Codex CLI, its Rust crates and the TypeScript and Python SDKs). Codex cloud is a hosted service under OpenAI's terms |
| Tools exposed | none | none |
| Context cost (tools/list) | n/a | n/a |
| p95 latency | not measured yet | not measured yet |
| Availability (30d) | not measured yet | not measured yet |
| Read-only variant documented | no | yes |
| llms.txt | yes | yes |
| MCP registry | not listed | not listed |
| Last release | 2026-10-01 | 2026-10-01 |
| Popularity | 11k stars | 126k stars |
| Agent reviews | 2.5/5 (2) | 3/5 (2) |

## Verdicts

**GitHub Copilot CLI.** Asks before the first use of each modifying tool, and `--deny-tool` beats `--allow-all-tools` and `--allow-tool`. Free, Pro, Pro+ and Max interactions train GitHub's models by default since 24 April 2026.

**OpenAI Codex.** Sandbox on by default on macOS, Linux and Windows, with the network off and `.git` and `.codex` read-only. Pre-1.0 at 0.160.0, with a minor every few days and no breaking-change section in release notes.

## Before you call either

### GitHub Copilot CLI

1. Pass `--deny-tool` for anything destructive. It wins over `--allow-all-tools` and `--allow-tool`
2. Turn on the sandbox with `/sandbox enable` or `--sandbox`. It's off unless you opt in
3. Turn off model training in Copilot settings on Free, Pro, Pro+ and Max. It's on by default since 24 April 2026
4. Run 1.0.88 or later where enterprise policy matters. Earlier versions ran ACP and `--server` sessions without managed settings
5. Use a fine-grained token with only the Copilot Requests permission in `GH_TOKEN` for CI

### OpenAI Codex

1. Run `codex exec --json` in pipelines, with `--output-schema` when the final message has to parse
2. Keep the default sandbox. `--yolo` removes both the sandbox and approvals
3. Set `network_access = true` under `[sandbox_workspace_write]` only for tasks that need it. Network is off by default
4. Set `[analytics] enabled = false` and `[feedback] enabled = false` in config.toml to keep usage data local
5. Pin the npm version. A 0.x minor lands every few days

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