Opencode: Configure Default Agents' Model

Out of the box open code supports two modes plan and build. Here is how you can make the configuration of these plans explicit and also define the models to be used for each.

In ~/.config/opencode/opencode.json:

{
  ...
  "agent": {
      "build": {
        "model": "anthropic/claude-haiku-4-5",
        "temperature": 0.3,
        "tools": {
          "write": true,
          "edit": true,
          "bash": true
        }
      },
      "plan": {
        "model": "anthropic/claude-sonnet-4-5",
        "temperature": 0.1,
        "tools": {
          "write": false,
          "edit": false,
          "bash": true,
          "exa": true
        }
      }
    }