How to Configure MCP Server & Permissions for Codex CLI in Laravel

Introduction: Why AI Assistants Need the Right Foundation

AI assistants are no longer futuristic add-ons — they are becoming the backbone of developer workflows, customer support, and content automation. But to make them reliable, secure, and consistent, you need the right environment configuration.

For Laravel developers, that means configuring the MCP (Model Context Protocol) server and permissions for Codex CLI. This ensures the assistant can read, write, and test within your codebase safely — without touching secrets or destructive files.

This guide will walk you through:

• What MCP servers are and why they matter
• How to configure mcp.json for Laravel
• Best practices for permissions and safety
• How Codex CLI integrates with Laravel workflows
• Limitations and common pitfalls

By the end, you’ll have a production-ready Codex CLI setup for Laravel projects.

Step 1: Understanding MCP in Plain English

MCP (Model Context Protocol) is the “bridge” between your AI assistant and your local project.

• Servers: Define tools the assistant can use (filesystem, shell, git, HTTP).
• Permissions: Control what the assistant can read/write/execute.
• Safety: Ensure .env, vendor/, and storage/ aren’t touched.

Think of MCP like a firewall for your AI assistant: it lets Codex CLI help you code but blocks anything unsafe.

Step 2: Creating a Project-Level mcp.json

Always place your MCP config at the project root, so teammates share the same setup.

Example Laravel-safe mcp.json:

{
  "version": "1",
  "servers": {
    "fs": {
      "command": "filesystem",
      "permissions": {
        "read": ["."],
        "write": [
          "app/",
          "config/",
          "database/",
          "resources/",
          "routes/",
          "tests/",
          ".github/",
          "composer.json",
          "composer.lock",
          "package.json",
          "vite.config.*",
          ".env.example"
        ],
        "deny": [".env", "storage/", "vendor/", "node_modules/"]
      }
    },
    "shell": {
      "command": "shell",
      "allow": [
        "php",
        "php artisan",
        "composer",
        "npm",
        "git",
        "pint",
        "pest"
      ],
      "deny": ["rm", "sudo", "shutdown", "reboot"],
      "workingDirectory": "."
    },
    "git": {
      "command": "git",
      "allow": ["status", "add", "commit", "diff", "restore", "log"],
      "autoStageOnWrite": true
    }
  }
}

✔ Safe defaults ✔ Allows coding & testing ✔ Blocks secrets and destructive commands

Step 3: How Codex CLI Uses Permissions

Codex CLI doesn’t automatically run commands or overwrite files. It:

1. Proposes diffs → you approve them.
2. Suggests shell commands → you approve or deny.
3. Logs everything, so you stay in control.

This workflow ensures speed with guardrails.

Step 4: Integrating MCP with Laravel Workflow

Here’s how Codex CLI fits into your daily Laravel dev cycle:

• Generate feature tests (Pest/PhpUnit)
• Refactor controllers into Actions
• Scaffold CI/CD pipelines (GitHub Actions, GitLab CI)
• Run Pint & Pest automatically on commits

Because MCP blocks .env and sensitive folders, Codex can’t expose secrets or corrupt storage.

Step 5: Best Practices for Permissions

1. Allow writes only where needed

   • app/, tests/, routes/ → ✅
   • .env, storage/, vendor/ → ❌

2. Limit shell commands

   • Safe: php artisan make:model
   • Unsafe: php artisan migrate --force in production

3. Use example envs

   • Commit .env.example for AI tasks
   • Never expose real .env

4. Commit often

   • Small commits reduce merge conflicts
   • Easier to roll back AI-generated changes

Step 6: Limitations of Codex CLI

Even with MCP configured, remember:

• Context window: Codex can’t “see” your entire repo at once. It only knows what it opens.
• No internet access: Unless you configure an HTTP server, Codex can’t fetch remote data.
• Approval needed: Nothing runs without your confirmation.
• Rate limits: Prolonged heavy sessions may trigger throttling (on Plus plans, usage is fair-use with some caps).

Step 7: Combining Codex CLI with Claude Code CLI

Yes — you can run both tools in the same Laravel repo. They both respect the same mcp.json.

Rules to avoid conflicts:

• Use one shared config (mcp.json at root).
• Work on separate branches for each assistant.
• Commit before switching tools.
• Add tool state dirs (.junie/, .claude/) to .gitignore.

This way, Codex and Claude won’t overwrite each other’s context.

Real-World Example: Menu Drag-and-Drop in Laravel

Imagine you’re fixing a nested menu drag-and-drop feature:

1. Ask Codex CLI: “Write a Pest feature test for MenuController@updateOrder with valid/invalid payloads.”

2. Approve generated tests → run pest.

3. Ask Codex CLI: “Fix the update logic in MenuController and refactor into App/Actions/Menu/UpdateOrder.php.”

4. Approve changes → tests pass → commit.

Result: A feature completed in half the time, with tests and refactor included.

Quick Takeaways

• MCP = firewall + toolkit for AI assistants
• Always use project-level mcp.json
• Block .env, vendor/, and destructive commands
• Codex CLI fits seamlessly into Laravel test-driven workflow
• Safe to run alongside Claude Code CLI with one config

Call to Action

Want a Laravel-ready AI coding assistant? Configure your MCP server today, commit a safe mcp.json, and let Codex CLI handle repetitive dev tasks while you focus on architecture.

FAQ

Q: Can Codex CLI accidentally expose .env? No — not if you deny .env in your mcp.json (recommended).

Q: Is MCP required to run Codex CLI? Yes — MCP defines what tools the assistant can use.

Q: Can Codex run database migrations? Only if you approve and whitelist php artisan migrate. For safety, restrict to testing environments.

Q: Can I use Claude and Codex together? Yes — as long as you share one mcp.json and keep changes in separate commits/branches.