[FEATURE]: add "/experimental" command to toggle experimental features

[robin-liquidium]

Feature hasn't been suggested before.

• I have verified this feature I'm about to request hasn't been suggested before.

Describe the enhancement you want to request

Codex CLI has a /experimental commands which makes it very streamlined and easy to toggle experimental features. OpenCode should have that too IMO to make experimental features easier to test and more streamlined.

[github-actions]

This issue might be a duplicate of existing issues or closely related to them. Please check:

• [FEATURE]: add "/plugins" commands to discover Plugins, MCPs, and Skills (like Claude Code) #7716: Requests adding "/plugins" command to discover Plugins, MCPs, and Skills - very similar intent of adding streamlined slash commands for feature management (like Claude Code)
• [FEATURE]: Disable plugins via cli #7687: Requests ability to disable plugins via CLI - shares the goal of streamlined feature toggling
• [FEATURE]: slash command for reload #6719: Requests "/reload" slash command for runtime configuration reloading
• [FEATURE]: Add slash command to show active instruction file paths in a session #7679: Requests slash command to show active instruction file paths
• [FEATURE]: Let LLM enable MCP on demand, default all MCPs off #7466: Discusses toggling MCP features on/off dynamically

Feel free to ignore if your specific use case differs from these existing requests.

[todor-a]

This would be awesome to have. I always forget to toggle on experimental plan mode 🤦

[github-actions]

To stay organized issues are automatically closed after 90 days of no activity. If the issue is still relevant please open a new one.