Set up personal harness instructions

Create or update personal instructions through each selected harness's native mechanism. Keep its built-in system prompt intact. This skill changes only the selected instruction destinations, leaving configuration and legacy files unchanged. It requires file-editing access for file targets; no installer or PowerShell dependency.

1. Select harnesses and languages

Ask which harness or harnesses to configure. Offer Codex, Cursor, and Claude Code; reuse selections already explicit in this request rather than asking again. Codex is one choice covering the app and CLI, which share user instructions under the same CODEX_HOME. The current host is not an implicit selection. Confirm the machine/profile when it affects the destination. Default to personal, cross-project scope.