Cross-host matrix (concise)
| Area | Claude Code | Codex | Cursor | OpenCode |
|---|---|---|---|---|
| Primary project instructions | CLAUDE.md | AGENTS.md | .cursor/rules/*.mdc | AGENTS.md |
| Plugin command model | supported | use @plugin + skills | supported | supported |
| Hooks model | plugin + settings | external hooks config | hooks.json | plugin runtime hooks |
| Skill limits (notable) | short display truncation | 1024-char description cap | strict name/path expectations | plugin-managed skill loading |