based on claude-code-best-practice and codex-cli-best-practice
┌─────────────────────────────────────────────────────────────────────────┐
│ CROSS-MODEL CLAUDE CODE + CODEX WORKFLOW │
├─────────────────────────────────────────────────────────────────────────┤
│ │
│ STEP 1: PLAN Claude Code │
│ ───────────── Opus 4.6 │
│ Open Claude Code in plan mode (Terminal 1). Plan Mode │
│ Claude interviews you via AskUserQuestion. │
│ Produces a phased plan with test gates. │
│ │
│ Output: plans/{feature-name}.md │
│ │
│ ▼ │
│ │
│ STEP 2: QA REVIEW Codex CLI │
│ ────────────────── GPT-5.4 │
│ Open Codex CLI in another terminal (Terminal 2). │
│ Codex reviews plan against the actual codebase. │
│ Inserts intermediate phases ("Phase 2.5") │
│ with "Codex Finding" headings. │
│ Adds to the plan — never rewrites original phases. │
│ │
│ Output: plans/{feature-name}.md (updated) │
│ │
│ ▼ │
│ │
│ STEP 3: IMPLEMENT Claude Code │
│ ────────────────── Opus 4.6 │
│ Start a new Claude Code session (Terminal 1). │
│ You implement phase-by-phase │
│ with test gates at each phase. │
│ │
│ ▼ │
│ │
│ STEP 4: VERIFY Codex CLI │
│ ──────────────── GPT-5.4 │
│ Start a new Codex CLI session (Terminal 2). │
│ Codex verifies the implementation │
│ against the plan. │
│ │
└─────────────────────────────────────────────────────────────────────────┘
Last Updated: 2026-03-06