Codex: Codex IDE Extension

1. Open VS Code
2. Click the Extensions icon on the left (or Ctrl+Shift+X)
3. Search for "Codex"
4. Click Install
5. Log in with your ChatGPT account

1. Open Cursor
2. Search for "Codex" in the extension marketplace
3. Install
4. Log in with your account

// Select this code
function formatDate(date) {
  return date.toISOString();
}

// Right-click → Codex: Edit → "Add localization support, support Chinese date format"

// After Codex modifies
function formatDate(date: Date, locale: string = "zh-CN"): string {
  return new Intl.DateTimeFormat(locale, {
    year: "numeric",
    month: "long",
    day: "numeric",
  }).format(date);
}

Ctrl+Shift+P → "Codex: Generate" → Enter description

// Alice presses Ctrl+Shift+P in VS Code
// Enters "Codex: Generate"
// Description: "Create a React Hook that manages pagination state, including page number, page size, and total count"

// Codex generates:
import { useState, useCallback } from "react";

interface PaginationState {
  page: number;
  pageSize: number;
  total: number;
}

export function usePagination(initialPageSize: number = 20) {
  const [state, setState] = useState<PaginationState>({
    page: 1,
    pageSize: initialPageSize,
    total: 0,
  });

  const setPage = useCallback((page: number) => {
    setState((prev) => ({ ...prev, page }));
  }, []);

  const setTotal = useCallback((total: number) => {
    setState((prev) => ({ ...prev, total }));
  }, []);

  const totalPages = Math.ceil(state.total / state.pageSize);

  return { ...state, totalPages, setPage, setTotal };
}

Select code → Right-click → "Codex: Review"

Select code → Right-click → "Codex: Explain"

1. Enter "Fix type errors in the current file" in the sidebar
2. Codex automatically reads the file open in the editor
3. Displays diff directly in the editor
4. Click Apply to accept changes

{
  "codex.model": "gpt-5-codex",
  "codex.sandboxMode": "workspace-write",
  "codex.autoApply": false,
  "codex.contextFiles": ["AGENTS.md", "tsconfig.json"],
  "codex.excludePatterns": ["node_modules/", "dist/"]
}