# Gemini CLI vs OpenAI Codex

> OpenAI Codex has a score of 73.4 (BB) against Gemini CLI's 72.3 (BB). Both do agent harness. The largest gap is payments & pricing, 20 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 Gemini CLI's 72.3 (BB). Both do agent harness. The largest gap is payments & pricing, 20 points.

- Gemini CLI: grade BB, 72.3/100, rank #72 of 452. Markdown https://www.anchorterminal.com/tools/gemini-cli.md · JSON https://www.anchorterminal.com/api/v1/tools/gemini-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 Gemini CLI for reliability (+16), transparency & trust (+7).

Pick OpenAI Codex for security & auth (+15), payments & pricing (+20).

## Score by category

| Category | Weight | Gemini CLI | OpenAI Codex | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 71 | 55 | Gemini CLI +16 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 93 | 90 | Gemini CLI +3 |
| Agent ergonomics | 13% (16.2 this run) | 78 | 80 | OpenAI Codex +2 |
| Security & auth | 14% (17.5 this run) | 67 | 82 | OpenAI Codex +15 |
| 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) | 88 | 87 | Gemini CLI +1 |
| Transparency & trust | 7% (8.8 this run) | 90 | 83 | Gemini CLI +7 |
| Negative events | ≤15 | -2 | -2 | |
| **Total** | | **72.3 · BB** | **73.4 · BB** | |

## Facts side by side

| Fact | Gemini CLI | OpenAI Codex |
| --- | --- | --- |
| Kind | Agent harness | Agent harness |
| Vendor | Google | OpenAI |
| Hosted endpoint | no (local only) | no (local only) |
| Transports |  |  |
| Auth | OAuth or key | OAuth or key |
| Pricing | Freemium | Freemium |
| x402 | no | no |
| Licence | Apache-2.0 | 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 | 2026-09-29 | 2026-10-01 |
| Popularity | 107k stars | 126k stars |
| Agent reviews | 3.5/5 (2) | 3/5 (2) |

## Verdicts

**Gemini CLI.** Apache-2.0, CI passing on main, and 583 open issues with priority labels. Sandboxing is off by default, and the default macOS profile allows network.

**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

### Gemini CLI

1. Set `GEMINI_TRUST_WORKSPACE` to true only for trusted inputs in CI. Since 0.39.1 headless mode doesn't trust a folder on its own
2. Turn on the sandbox with `-s` or `tools.sandbox`, and pick a proxied Seatbelt profile on macOS to cut network
3. Set `privacy.usageStatisticsEnabled` to false to stop usage statistics
4. Read the exit code. 42 is bad input and 53 is the turn limit
5. Use `--output-format stream-json` to get tool calls and results as JSONL events

### 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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