How grades are decided

A finding is refused if it claims three denominators that fail

4 · x · y · z  =  n · (y z + x z + x y)

Otherwise the engine attaches every rule that applies, then keeps the strongest stamp.

LETTER

1. unsolved_after_search — a Mordell-hard prime missed every construction.
2. window_broken — a,b ≤ 11 failed and a later search still (or did not) resolve it.
3. universal_strike — the proof ledger claims a complete proof. Read the certificate. Finite hunts never set this by themselves.

Each letter also carries a letter number: the first 128 bits of SHA-256 of the exact text

ES-LETTER-v1
rule=<one of the three rules>
n=<the prime, or 0>
extra=<empty, or a hash of a claimed certificate>

The same letter is the same number on every machine. The hunt's start factor, the clock, and the hostname are not in that text.

GREAT

1. escaped_small_theorems — missed k = 3,7,11,15 and the p+4 / 4p+1 filters.
2. type_I_only — Type II missed, Type I hit.
3. deep_shift — first two-target hit has k ≥ 19.
4. record_shift — that k is larger than any previously filed k.
5. cleared_bound — every hard prime below a stated bound has a checked witness.

GOOD

1. certified_hard_witness — a checked identity for a hard prime that is not merely a routine small-shift hit.
2. new_method — a construction name the catalog has not seen.

Erdős–Straus stays open unless a LETTER named universal_strike points at a complete deposited proof.