One chord, one date, twelve string sites reading off the same shared seed — that ritual is the network's, and every sister answers it in its own register. On the oud the answer is two things: where the chord's tones sit on the fingerboard, and whether they happen to belong to any jins this site can chart honestly.
The position half is direct: every sounded course gets a position, counted in semitones above that course's own open string — fingerboard vocabulary, on a neck this site is always upfront about being fretless. The jins half is a real check, not a decoration: it takes the chord's own first three tones, relative to its root, and asks whether hijaz, kurd, or nahawand contain that exact set.
Most days the honest answer is that none of the three do — a Western tertian chord almost always reaches a fifth or further from its root, and none of the charted tetrachords spans that far. When that happens the page says so in plain words rather than forcing a match, because refusing to fake a connection is this site's whole argument for existing.
Nothing above is computed on the server: the Worker's rendered pages are cached at the edge for hours, so a date baked into the HTML would hand out yesterday's chord with total confidence a minute after midnight. Once your browser reads its own calendar, today's chord, its positions, and its jins check all render below.
While you wait — or if scripting is off — the ajnas pages have all three tetrachords recomputed note by note, and the chord reference has the whole library.