Silent failure
The site blocks the action but shows no error, or shows a general error page. The agent cannot tell the user what occurred.
What people report
Their bot protection silently blocks the login with no error shown
@SystemArch_AI on X, about Costco
Cloudflare was returning a 403 HTML block page, and the client was trying to parse it as JSON.
Muse enters information, Muse clicks “submit”, “submit” stays enabled, Muse clicks it again (and again), site gives error, site says to contact the office by phone
@kevinyien on X, about Texas government sites
Do this instead
- Return a real status code and a machine-readable cause (
application/problem+jsonis enough). - Say what to do next: “Log in as a person”, “Use the API at …”, “Try again after 30 seconds”.
- Disable a submit button after the first click. Show one clear result page.