cmux Socket Policy

Threading policy

• Do not use DispatchQueue.main.sync for high-frequency socket telemetry commands such as report*, portskick, status/progress updates, or log metadata updates.
• For telemetry hot paths, parse and validate arguments off-main.
• Dedupe and coalesce off-main first.
• Schedule minimal UI/model mutation with DispatchQueue.main.async only when needed.
• Commands that directly manipulate AppKit/Ghostty UI state are allowed to run on the main actor.
• If adding a new socket command, default to off-main handling and require an explicit reason in code comments when main-thread execution is necessary.

Focus policy

• Socket/CLI commands must not steal macOS app focus.
• Do not activate the app or raise windows unless the command has explicit focus intent.
• Only explicit focus-intent commands may mutate in-app focus/selection.
• Explicit focus-intent commands include window.focus, workspace.select/next/previous/last, surface.focus, pane.focus/last, browser focus commands, and v1 focus equivalents.
• All non-focus commands should preserve the current user focus context while still applying data/model changes.

Detailed reference

• Read [references/threading-and-focus.md](references/threading-and-focus.md) when adding a command, changing command execution context, or deciding whether focus changes are allowed.