OpenAI Codex CLI vs Devstral
Which AI coding tool should you choose? Feature, pricing, and workflow comparison for 2026.
Quick Comparison
OpenAI Codex CLI
OpenAI's CLI tool for AI-assisted coding. Uses OpenAI's o-series models.
| Pricing | API usage-based |
| Type | Tool |
Devstral
Mistral's open-weight coding agent. Designed for autonomous code generation and terminal-based development workflows.
| Pricing | Free open source, API usage-based via Mistral platform |
| Type | Tool |
Key Differences
OpenAI Codex CLI is a versatile AI coding tool. Devstral offers a different approach.
Choose OpenAI Codex CLI if you want terminal-based AI coding. Choose Devstral if you prefer a different coding workflow.
Best AI Models to Use with OpenAI Codex CLI and Devstral
Both tools support multiple AI models. Here are the most cost-effective options ranked by value.
| # | Model | Provider | Input ($/M) | Medium Project | Context |
|---|---|---|---|---|---|
| 1 | Gemini 2.5 Flash Lite | $0.037 | $0.04 | 1M tokens | |
| 2 | Gemini 1.5 Flash | $0.075 | $0.09 | 1M tokens | |
| 3 | Qwen Turbo | Qwen | $0.080 | $0.08 | 1M tokens |
| 4 | Gemini 2.0 Flash | $0.100 | $0.12 | 1M tokens | |
| 5 | Mistral Small 3 | Mistral | $0.100 | $0.10 | 32K tokens |
| 6 | Microsoft Phi-4 | Microsoft | $0.100 | $0.10 | 128K tokens |
| 7 | Gemma 3 27B | $0.100 | $0.12 | 128K tokens | |
| 8 | GPT-4o mini | OpenAI | $0.150 | $0.18 | 128K tokens |