My first vibe-coded app was invisible to ChatGPT.

GraspAi: built fast, read badly

GraspAi was my first app built with AI. It turns study material into flashcards, quizzes and summaries. It looked finished, it worked, and people could use it. So I assumed ChatGPT, Claude and Perplexity could read it too.

They mostly couldn’t. When I ran the first Unvibe checkup, GraspAi scored 35 out of 100. AI crawlers don’t run JavaScript, and most of what made the page make sense only appeared after it loaded. What was left in the HTML didn’t clearly say what the app was, who it was for or what it cost. An assistant asked about it had little to go on.

“Published” isn’t the same as “readable”. My app was live, but to an AI it was mostly blank.

What I changed

I didn’t rewrite the app. Unvibe listed each problem as a fix ready to paste into my coding agent, and I worked through them one at a time:

1. Copied each fix from the report into my coding agent, which changed the code.
2. Deployed, then ran a new checkup to confirm each fix on the live site.
3. Repeated until the important ones were green.

GraspAi went from 35 to 80. Now, when an AI reads the homepage, it can say what GraspAi is and who it’s for, from the page alone.

Unvibe: 93, and a setting I didn’t know about

Then I checked Unvibe itself. It scored 93, and the one failing check made no sense at first: it said robots.txt was blocking GPTBot and ClaudeBot. My robots.txt allowed every crawler.

The file I wrote wasn’t the problem. My domain runs through Cloudflare, and a “block AI training bots” setting was quietly swapping my robots.txt for one that turned away GPTBot, ClaudeBot and Google-Extended. Anyone opening the file from my laptop saw mine. AI crawlers saw Cloudflare’s.

One switch in the Cloudflare dashboard fixed it, and the next checkup came back 100 out of 100. That’s why Unvibe now also visits every site as the real AI crawlers (GPTBot, ClaudeBot, PerplexityBot and Googlebot) and flags any site that treats them differently from a browser.

What I learned

• AI tools build apps that look right to people. Being readable by AI is a separate job, and no one tells you to do it.
• The fixes are small. A clear first line, real text in the HTML, structured data, a sitemap, crawlers let in. A coding agent can do most of them in minutes.
• Check what AI actually gets. My robots.txt was fine. What reached the crawlers wasn’t. You only see that by checking as they do.