u/EasyDev_

My entire project was built around Copilot CLI.
but about a week ago I migrated to Opencode.

Because I realized model policies can shift drastically at any moment.

Copilot probably saw this coming too. That's likely why they added external model support
but how much you can actually trust that is still an open question.

Current setup: plan / build runs on Codex
(still have credits left, so alternating with Copilot)
everything else handled through Copilot.

// opencode.json
{
  "$schema": "https://opencode.ai/config.json",
  "permission": "allow",
  "small_model": "github-copilot/gpt-5-mini",
  "agent": {
    "plan": {
      "model": "openai/gpt-5.4",
      "reasoningEffort": "xhigh",
    },
    "build": {
      "model": "openai/gpt-5.4",
      "reasoningEffort": "xhigh",
    },
    "title": {
      "model": "github-copilot/gpt-5-mini",
      "reasoningEffort": "low"
    },
    "compaction": {
      "model": "github-copilot/gpt-5.4-mini",
      "reasoningEffort": "low"
    },
    "general": {
      "model": "github-copilot/gpt-5.4-mini",
      "reasoningEffort": "medium"
    },
    "explore": {
      "model": "github-copilot/gpt-5-mini",
      "reasoningEffort": "low"
    }
  },
}

Long-term I see it drifting toward a hybrid structure
top-tier models from Tier 1 providers
everything else routed through OpenRouter or similar.