BEFORE: Vorhandenheit (breakdown)
─────────────────────────────────────────
╭──────╮ ╭──────╮ ╭──────╮
╱ Input ╲══▶╱Server ╲══▶╱ ??? ╲
│ ✓ │ │ ✓ │ │ ✗FAIL │
╲ ╱ ╲ ╱ ╲ ╱
╰──────╯ ╰──────╯ ╰──────╯
"failed to
upload image"
AFTER: Zuhandenheit (transparent)
─────────────────────────────────────────
╭──────────╮
╱ Input ╲───▶ ✓ proceeds
│ ⚠ 142 chars │
╲ ╱───▶ ✗ rename
╰──────────╯
The tool recedes; the work continues.
Validation as Zuhandenheit: Preventing Tool Breakdown Through Proximity
A case study in form validation through a Heideggerian lens. When users upload files with 100+ character names, the downstream Admin system fails with a cryptic "failed to upload image" error. By moving validation to the input boundary, we prevent Vorhandenheit—the moment when tools stop serving and start obstructing.