Launch OpenCode and Use Model Variants
Once installation and configuration are complete, this is the runtime flow for actually using OpenCode day to day.
Launch OpenCode
Section titled “Launch OpenCode”opencodeModel switching basics
Section titled “Model switching basics”- Use
/modelsto switch models during a session - CLIProxyAPI models appear as
cliproxyapi/gpt-5,cliproxyapi/gpt-5.4, and similar names - Use the variant cycle keybind to move between reasoning levels such as low, medium, high, and xhigh when the selected model supports them
oh-my-openagentagents are available through@mentions
Model reference
Section titled “Model reference”Available models and their thinking levels
Section titled “Available models and their thinking levels”| Model | Thinking Levels | Context | Output |
|---|---|---|---|
| GPT-5 | minimal, low, medium, high | 400K | 128K |
| GPT-5 Codex | low, medium, high | 400K | 128K |
| GPT-5 Codex Mini | low, medium, high | 400K | 128K |
| GPT-5.1 | none, low, medium, high | 400K | 128K |
| GPT-5.1 Codex | low, medium, high | 400K | 128K |
| GPT-5.1 Codex Mini | low, medium, high | 400K | 128K |
| GPT-5.1 Codex Max | low, medium, high, xhigh | 400K | 128K |
| GPT-5.2 | none, low, medium, high, xhigh | 400K | 128K |
| GPT-5.2 Codex | low, medium, high, xhigh | 400K | 128K |
| GPT-5.3 Codex | low, medium, high, xhigh | 400K | 128K |
| GPT-5.3 Codex Spark | low, medium, high, xhigh | 128K | 128K |
| GPT-5.4 | low, medium, high, xhigh | 1.05M | 128K |
Choosing models in practice
Section titled “Choosing models in practice”- GPT-5.4 is the best default for long-context reasoning and bigger cross-file work
- GPT-5.3 Codex is a good default for coding-heavy implementation tasks
- lighter fallback models are useful for exploration and low-cost background work