The Library Said It Worked

The failure these share

The library returned. That is all it did. Nothing in the return value says the answer is wrong, and the calling code has no second source to check it against.

• Library Verdicts — what six libraries your agent picked from download counts actually do at the edge.
• Pillow Truncated Load Verdict — the incomplete image loads, reports the right dimensions, and is three-quarters flat grey.
• Trafilatura Extraction Confidence — `extract()` returns a string for a navigation bar and for a paywall notice. All 21 output fields checked; there is no confidence field.
• Extraction Contract Verdict — `charThreshold` is documented and not enforced: set it to 100000 and a footer copyright line still comes back as the article.
• Upload Verdict — `mime-types` says a Windows executable named invoice.pdf is a PDF.
• Registrable Domain — `tldts` says every GitHub Pages tenant is the same owner.
• Safe Filename — `sanitize-filename` returns an empty string for `CON.txt`.
• Device Capability Verdict — `/Safari/.test(ua)` is true for Chrome, Edge, Opera and Samsung Internet.

Why buy them together

They are the same habit: trusting a return value because it has the right type. The eight sit across parsing, extraction, upload and detection, which is most of the surface where untrusted input becomes a decision.

Each ships with its own tests and is sold separately. This is the set, below the sum.