AI Product Index / robots.txt published
Its absence is ambiguous rather than permissive, and several crawlers resolve ambiguity as "stay out". This is the cheapest check on the list to pass.
This check concerns site information and access. Consider your intended audience and publishing policy before making a change.
Publish /robots.txt — its absence is ambiguous, and some crawlers treat ambiguity as disallow.
# /robots.txt
User-agent: *
Allow: /
Sitemap: {{ORIGIN}}/sitemap.xml
Free, no signup, same endpoint that produced every grade on the leaderboard:
curl "https://index.percall.dev/api/score?url=https://your-site.example"
It returns the letter grade and every check by name with pass/fail. The
$0.05 call at POST /api/audit adds why each one failed and a
snippet with your origin already in it.