Add an opt-in OpenCode plugin that replaces the built-in provider behavioral prompt with a minimal identity while preserving environment, project, MCP, skill, history, and tool context.
Track the active agent per session and apply the transform only to build and plan. Keep plan/build mode reminders and permission enforcement owned by OpenCode, leave all other agents untouched, and fail safely when the expected prompt boundary is absent.
Expose the feature in Behavior settings with localized guidance, explicit Save + Reload application, settings search integration, persisted boolean validation, and managed-runtime lifecycle composition that does not load the plugin while disabled or on external OpenCode servers.
Document the runtime contract and cover plugin materialization, config preservation, build/plan selection, agent switching, unknown prompt formats, and settings sanitization.
Bohdan Triapitsyn
3cf1d82106