Build a 99/100 SEO Website with GPT 5.6 Codex

The complete playbook for building a Google Lighthouseโ€“optimized, animated website from scratch using AI โ€” from keyword research to live deployment in one session.

99
Lighthouse Score
7
Tools Connected
~$8
Video Gen Cost

๐Ÿ“‹ Full Guide Contents

  1. Tool Stack & Connections
  2. Keyword Research & Business Truth
  3. Page Structure & Sitemap Planning
  4. Verify Page Structure & CTAs
  5. Visual System & Video Generation
  6. Website Build in Astro
  7. Lighthouse Testing & Optimization
  8. Domain & Cloudflare Deployment
  9. Google Analytics & Search Console
  10. Sitemap Submission & Launch Checklist
  11. Copy-Paste Prompts
  12. Pre-Launch Checklist
Phase 1

Tool Stack & Connections

Every tool in this stack is chosen because they integrate natively with GPT 5.6 Codex. The goal: never leave the GPT application to build, optimize, and deploy.

๐Ÿ›  Required Tools

GPT 5.6 Codex
The AI engine. Use the new desktop app with Codex mode (not GPT Work). Handles code generation, SEO optimization, and deployment orchestration.
Core Engine
Data for SEO
Provides real keyword data, search volumes, and competitive metrics. Cheaper than Ahrefs/SEMrush. Connected via MCP plugin.
SEO Data
Cloudflare
Free hosting, CDN, DNS, and SSL. Official plugin available in GPT's plugin store. Manages deployment without leaving the app.
Hosting & CDN
21st Dev
Design inspiration library with copy-pasteable UI components, scroll animations, and layout references. Connects via MCP.
Design Inspiration
Astro Framework
Static site generator with built-in SEO optimizations โ€” sitemap, structured data, meta tags, and performance out of the box.
Framework
GSAP
GreenSock Animation Platform. Industry-standard scroll-triggered animations. GPT installs it as a dependency during build.
Animations
FAL.ai
Pay-as-you-go AI video/image generation. Replaces subscriptions like Higgsfield. Supports Kling 3, Seed Dance, and more models.
Video / Image Gen

๐Ÿ”Œ Connection Setup

1

Connect Data for SEO

Follow the dedicated setup video (linked in original video description). This gives Codex access to real keyword data โ€” search volume, CPC, competition metrics.

2

Install the Cloudflare Plugin

In the GPT app โ†’ Plugins โ†’ search "Cloudflare" โ†’ install the official Cloudflare plugin. Grant all required permissions so it can manage DNS, Pages, and deployments. Works with free Cloudflare tier.

3

Connect 21st Dev via MCP

Go to 21st.dev โ†’ Setup โ†’ CLI & MCP โ†’ select Codex. Copy the full configuration prompt. Paste it into a new Codex conversation and run. This gives your AI direct access to browse and import UI components and scroll animations.

4

Connect FAL.ai (for video/image generation)

Add credits at fal.ai (pay-as-you-go, ~$8 covers a full project). Install as a plugin in the GPT app. All generated media is saved to your FAL dashboard for reuse.

๐Ÿ’ก Why these specific tools? Every tool here has a native GPT plugin or MCP integration. This means you can build, optimize, generate media, and deploy โ€” all from a single Codex conversation without switching apps.

โšก Tools That Don't Need Pre-Installation

GSAP and Astro are installed as project dependencies by Codex during the build. You just tell it to use them โ€” it handles the rest via npm.

Phase 2

Keyword Research & Business Truth

This is the most important phase. A beautiful website that targets the wrong keywords is worthless. You need to extract every transactional keyword the business can claim.

โš ๏ธ The #1 Mistake

Business owners describe their services in industry jargon, but customers search using completely different language.

๐Ÿ” Example: EV Charging Business
  • Business says: "EV charging solutions," "Level 2 charging infrastructure"
  • Customer searches: "EV charger installation cost," "Tesla wall charger installer near me"
  • The gap: If you only target industry terms, you miss 80% of potential traffic.

๐Ÿ“ How to Extract Business Truth

1

Create a New Codex Project

In the GPT app, go to Projects โ†’ click + โ†’ name it after the business (e.g., "Dog Training Business"). This keeps all context, files, and conversations organized.

2

Upload the MD Prompt Files

Place the 4 provided MD files into the project folder. Tell Codex: "Understand all these documents. Don't act on them. Save them in this folder for reference."

3

Fill Out the Business Brief

Open the "103 Copy-Paste Prompt" MD file. Either fill it out manually or ask GPT to help. This captures: services offered, service areas, target customers, unique selling points, and desired call-to-action.

4

Run the Keyword Research Prompt

After filling the brief, Codex will produce:

  • A keyword research CSV with volumes, CPC, and competition
  • Keyword clusters grouped by transactional intent
  • A recommended sitemap based on those clusters
๐Ÿ“Š What "Transactional Keywords" Means These are search terms where the person is ready to buy or book โ€” not just browse. Examples: "EV charger installation cost," "dog training near me," "emergency plumber Austin." These become your service pages.

๐ŸŽฏ Output: Your Keyword-Driven Sitemap

Codex will recommend a structure like:

/                           โ†’ Homepage
/services/ev-charger-installation/
/services/tesla-wall-connector/
/services/level-2-charger/
/areas/austin/
/areas/dallas/
/guides/ev-charger-cost-guide/
/guides/best-home-ev-chargers/

Each URL is driven by a real keyword cluster with search volume data backing it up.

Phase 3

Page Structure & Sitemap Planning

With keyword research complete, Codex auto-generates the site architecture. Every page exists because there's a keyword cluster justifying it.

๐Ÿ“ What Codex Produces

๐Ÿ— Template Strategy

You don't design every page individually. You build 3 core templates:

Service Page Template
Hero โ†’ Service description โ†’ Benefits โ†’ Process steps โ†’ FAQ schema โ†’ CTA. One per keyword cluster.
Location Page Template
Location hero โ†’ Services in that area โ†’ Local trust signals โ†’ Map embed โ†’ CTA. One per service area.
Blog/Guide Template
Title โ†’ Table of contents โ†’ Content sections โ†’ Internal links to services โ†’ CTA. For informational keywords.
๐Ÿ’ก Pro Tip: Build the homepage first, then the service page template, then replicate. This lets you establish the design system once and scale it across 20+ pages in minutes.
Phase 4

Verify Page Structure & CTAs

Before any design work, review the planned structure. Don't let Codex run unsupervised on strategy.

โœ… What to Verify

โš ๏ธ Don't Skip This This is your chance to catch strategic errors before investing time in design and content. A wrong page structure means building the wrong website.
Phase 5

Visual System & Video Generation

Now for the fun part. This is where you decide the visual identity and whether to include scroll-triggered video animations.

๐ŸŽจ Building the Style Guide

Use GPT's image generator (or your preferred tool) to explore visual directions:

  1. Generate 5-10 hero images in different styles
  2. Test color palettes โ€” dark vs. light, bold vs. subtle
  3. Find a style that feels premium, not "AI-generated"
  4. Save the winning style as a reference for all future generations
๐Ÿ–ผ Important: When prompting, specify you want to use the built-in GPT image generator, not an API you may have connected previously. This avoids unexpected outputs.

๐ŸŽฌ AI Video Generation with FAL.ai

For scroll-triggered animations (like a video of someone plugging in an EV charger that plays as you scroll), you need video clips.

The Scene-Between Technique

AI video generators work best when you give them keyframes, not blank prompts:

1

Generate 3-4 Keyframe Images

Create still images of the key moments: (1) hand reaching for charger, (2) charger lifted, (3) charger being moved toward car, (4) charger plugged in.

2

Feed Keyframes to FAL.ai

Upload the keyframes and ask FAL to generate a smooth video interpolating between them. Test multiple models โ€” Kling 3 works best for realistic motion.

3

Export Frame-by-Frame

Once you have a video you like, export every frame as individual images. These get attached to GSAP scroll triggers so the video plays forward/backward as the user scrolls.

4

Tell Codex to Implement the Scroll Animation

Give Codex the frame sequence and tell it to wire up GSAP ScrollTrigger to play the frames based on scroll position.

๐Ÿ’ฐ Cost: All image and video generation for a full project costs approximately $8 on FAL.ai (pay-as-you-go). This is why FAL is preferred over subscription tools like Higgsfield โ€” you only pay for what you generate.

๐Ÿ“ธ Saving 21st Dev Components

As you browse 21st.dev for inspiration:

  1. Find components you like (display cards, aurora backgrounds, text animations)
  2. Click Save on each one
  3. Later, tell Codex: "Import the saved aurora background component from 21st Dev"
  4. Codex fetches and integrates it via the MCP connection
Phase 6

Website Build in Astro

The actual construction. This is where everything comes together โ€” SEO structure, visual design, animations, and content.

๐Ÿš€ Why Astro?

FeatureAstroPlain HTML
SEO SitemapAuto-generated pluginManual creation
Meta TagsBuilt-in head managementHand-code every tag
Structured DataEasy integrationManual JSON-LD
PerformanceZero JS by defaultVaries
Static OutputPre-rendered HTMLAlready static
โš ๏ธ Verify It's Actually Astro Check your local dev server. If the URL doesn't start with localhost:4321, Codex may have built it in plain HTML instead. The MD instructions should prevent this, but double-check.

๐Ÿ”จ Build Order

  1. Homepage โ€” establishes the design system, color palette, typography
  2. Service page template โ€” hero + content + FAQ + CTA + schema
  3. Replicate for all service pages using keyword data
  4. Location page template โ€” if applicable
  5. Blog/guide templates โ€” for informational content
  6. Global elements โ€” header, footer, navigation

๐ŸŽž Adding GSAP Animations

For any section where you want motion, describe the animation and tell Codex to use GSAP:

For the hero section, add a GSAP ScrollTrigger animation where the heading fades in and slides up from 30px below when it enters the viewport. Use a 0.8s duration with an ease of "power2.out".

๐Ÿ” Checking Structured Data

Every service page should have:

๐Ÿ’ก Testing Structured Data: Open Chrome DevTools โ†’ inspect the page โ†’ search for application/ld+json. Or use Google's Rich Results Test after deployment.

๐Ÿ–ผ Annotate Feature for Quick Edits

In the GPT desktop app, you can preview the local site and use the Annotate feature:

  1. Click Annotate โ†’ select any element on the page
  2. Type your change: "Generate a different hero image" or "Change this heading to..."
  3. Codex makes the change and hot-reloads

This isn't as fast as editing code directly, but it's great for quick visual tweaks without leaving the app.

Phase 7

Lighthouse Testing & Optimization

Before deploying, you must hit 99-100% on every Lighthouse category while still on localhost.

๐Ÿ”ฌ Running the Test

1

Open Chrome DevTools

Three dots (โ‹ฎ) โ†’ More Tools โ†’ Developer Tools. Click the Lighthouse tab (you may need to click >> to find it).

2

Configure the Test

Select Desktop mode. Check Performance, Accessibility, Best Practices, and SEO. Click "Analyze page load".

3

Interpret Results

You need 99-100 across all categories. If anything is below 80%, it needs fixing before deploy.

๐Ÿ”ง The Fix Prompt

If scores are low, copy the entire Lighthouse results and use this prompt:

This was the result of the Google Lighthouse test: [PASTE FULL RESULTS] We need to make sure everything is at least at 99-100% before we publish. Please fix all issues. IMPORTANT: Do NOT change any design elements, remove images, or alter the visual appearance just to improve performance scores. Optimize the code and loading strategy, but keep the design exactly as it is.
๐Ÿšจ Critical Warning Without the "don't change design" constraint, Codex will aggressively remove images, strip animations, and simplify layouts to chase a perfect score. Always specify that the visual design must be preserved.
Phase 8

Domain & Cloudflare Deployment

You've tested locally, you're happy with the scores. Time to go live.

๐ŸŒ Domain Setup

1

Buy a Domain on Cloudflare

Cloudflare Registrar โ†’ search for your domain โ†’ purchase. Domains are typically ~$10/year at cost price (no markup).

2

Or Transfer an Existing Domain

If you bought elsewhere, go to Cloudflare โ†’ Overview โ†’ Add a Site โ†’ follow the nameserver transfer instructions.

๐Ÿš€ Deploy with One Prompt

Once the domain is active in Cloudflare, go back to your Codex conversation and say:

Send this to Cloudflare and attach it to the domain [yourdomain.com]

Codex will:

  1. Build the Astro project for production
  2. Create a Cloudflare Pages project
  3. Deploy the built files
  4. Attach it to your domain
  5. Configure SSL automatically
๐Ÿ“‹ After Deployment: Check the Cloudflare deployment URL (staging URL) first to verify everything works. Then confirm the custom domain resolves correctly. SSL certificates are provisioned automatically by Cloudflare.

โœ… Post-Deploy Verification

Phase 9

Google Analytics & Search Console

Without these, you're flying blind. Install both before doing any ongoing SEO work.

๐Ÿ“ˆ Google Analytics 4 (GA4) Setup

1

Create a New GA4 Property

Google Analytics โ†’ Admin dropdown โ†’ Create โ†’ New Property. Name it, set the reporting timezone and currency.

2

Create a Web Data Stream

Select "Web" platform โ†’ enter your domain URL โ†’ name the stream โ†’ Create. You'll get a Measurement ID (G-XXXXXXXXXX).

3

Install the GA4 Tag via Codex

In your Codex conversation, say:

Install the GA4 tag with measurement ID G-XXXXXXXXXX on the live site. Deploy the change to Cloudflare.
4

Verify with Tag Assistant

Install the Google Tag Assistant Chrome extension. Visit your live site โ†’ click the extension โ†’ confirm the GA4 tag fires correctly.

๐ŸŽฏ Set Up Conversions

Tell Codex to track key actions as conversions:

Set up conversion tracking for form submissions on the contact page. When a user submits the form, fire a GA4 event called "generate_lead" with the form type as a parameter.

๐Ÿ” Google Search Console Setup

1

Add Property

Search Console โ†’ Add Property โ†’ enter your domain โ†’ Continue.

2

Auto-Verification via Cloudflare

If you're logged into both Google Search Console and Cloudflare with the same browser, it will automatically verify domain ownership. This is a Cloudflare integration benefit โ€” no DNS TXT record needed.

3

Submit Your Sitemap

In Search Console โ†’ Sitemaps โ†’ enter sitemap.xml โ†’ Submit. This tells Google exactly which pages to crawl and index.

๐Ÿ’ก Ongoing Management: Since Codex has access to both Cloudflare and GA/GSC data, you can manage the entire website from the GPT app. Ask it to analyze traffic patterns, suggest content improvements, or make changes โ€” and it can deploy them directly.
Phase 10

Sitemap Submission & Launch

The final steps to ensure Google can find, crawl, and rank your new site.

๐Ÿ—บ Sitemap Verification

Ask Codex: "What is the sitemap URL?" โ€” it should return something like:

https://yourdomain.com/sitemap.xml

Open it in your browser to verify:

๐Ÿค– AI Search Optimization

Beyond Google, you need to optimize for AI search engines (ChatGPT, Perplexity, etc.). This requires:

๐Ÿค– Real Result: One client using this exact approach closed a massive mortgage deal directly from a ChatGPT recommendation. The prospect literally said "ChatGPT said he was the best option." AI search is not optional in 2026 โ€” it's a revenue channel.
Prompts

Copy-Paste Prompts

These are the key prompts used throughout the process. Customize the bracketed sections for your project.

๐Ÿ“ฅ Initial Project Setup

I'm building a website for a [BUSINESS TYPE] in [LOCATION]. Services: [LIST ALL SERVICES] Target customers: [DESCRIBE IDEAL CUSTOMER] USP: [WHAT MAKES THEM DIFFERENT] CTA: [WHAT ACTION DO YOU WANT - call, form, booking] Using the attached MD files as reference, please: 1. Research transactional keywords for each service 2. Group them into keyword clusters 3. Recommend a sitemap structure based on search volume 4. Create a CSV of keyword data with volume, CPC, and competition

๐ŸŽจ Visual Direction

Generate a style guide for the [BUSINESS] website. I want: - A modern, premium look that doesn't feel AI-generated - Color palette: [dark/light] theme with [ACCENT COLOR] - Typography: clean, professional sans-serif - Generate 3 hero image options using the GPT image generator Save the winning style as a reference for all future pages.

๐Ÿ— Build Command

Build the website in Astro using the sitemap we planned. Requirements: - Use GSAP for scroll animations on the hero and key sections - Each service page needs: Service schema, FAQPage schema, BreadcrumbList schema - Location pages need LocalBusiness schema - Auto-generate sitemap.xml and robots.txt - Mobile-first responsive design - All images must have descriptive alt text Start with the homepage template, then the service page template.

๐Ÿš€ Lighthouse Fix

[PASTE FULL LIGHTHOUSE RESULTS] Fix all issues to get 99-100% on every category. CRITICAL: Do NOT remove images, animations, or change any visual design elements. Optimize code, loading strategy, and performance โ€” but keep the design exactly as it is.

๐Ÿ“ค Deploy

Deploy the site to Cloudflare Pages and attach it to [yourdomain.com]. Make sure SSL is configured and the sitemap is accessible at /sitemap.xml.

๐Ÿ“Š GA4 Installation

Install the GA4 measurement tag (G-XXXXXXXXXX) on the live site. Also set up conversion tracking for form submissions as "generate_lead" events. Deploy the changes.
Checklist

Pre-Launch Checklist

Run through this before going live. Check at minimum the homepage and 2-3 service pages.

โšก Performance

๐Ÿ” On-Page SEO

๐Ÿ“‹ Schema & Structured Data

๐Ÿค– AI Search Readiness

๐Ÿ”ง Technical

๐Ÿ“ฑ Cross-Device