Function install_tool_hooks_scoped 

pub fn install_tool_hooks_scoped(
    project_dir: &Path,
    sqz_path: &str,
    scope: InstallScope,
) -> Vec<String>

Like install_tool_hooks but lets the caller choose between project-local and user-global scope. This is the function sqz init and sqz init --global both call.

For InstallScope::Global:

• Claude Code hook is merged into ~/.claude/settings.json (the user settings file). We merge rather than overwrite because the user may already have permissions, env, statusLine, or other hooks there — blindly writing would nuke their config. Any existing sqz hook entries are replaced in place; unrelated fields are preserved.

• Cursor, Windsurf, Cline, Gemini CLI rules files don’t have a user-level equivalent that Cursor/etc. actually load. We keep those at project scope and note it in the plan. Users who want Cursor compressed across all projects should follow the Cursor docs (docs.cursor.com/en/context/rules) and add the rule at user scope manually — Cursor honours ~/.cursor/rules/*.mdc but only within workspaces that opt in.

• OpenCode plugin is already user-level by design (lives at ~/.config/opencode/plugins/sqz.ts), so scope doesn’t matter here.

• Codex MCP config is always user-level (~/.codex/config.toml). AGENTS.md stays per-project because that’s where it belongs.