R12 Researcher Interview Result

Status: canonical matched interview completed; all three checkpoints fail the locked state-transition board. Transcript reading localizes distinct computation, serialization, and iterative-consumption failures.

Frozen execution

All jobs completed 0:0 on CUDA under source commit e72c28770c2fb776e90673f1a9f580339c81a1a6. The three artifacts bind the same interview SHA-256 a72387a0a72418f119bf35791032bb889266b3f9ba8a3b728fc7f6978c0d4f8d, comparison-manifest SHA-256 032ebbf6980d23afcb01ed321a9890e792e725dcb72441d915694ab1b40998c0, and tokenizer SHA-256 87532df5c121753de3b29194e1f9e3de47986d3f5359548fdf93606773a233d4.

Locked scores

These are the official results. No post-hoc parser or prompt repair changes them.

Direct transcript diagnosis

The raw 200k checkpoint sometimes computes a useful local quantity while ignoring the requested interface. On RIV01 it emits 58+27=85; on RIV09 it emits the correct full sum 4786 + 5967 = 10753; and the RIV20 writer computes 31+14=45, 45*5=225. None is serialized into the requested state packet, and the gold-capsule reader answers 225 instead of applying -37,+6 to reach 194. This is local arithmetic evidence, not a board pass.

DRS changes the failure mode. Six of the first nineteen responses are parseable in the requested state grammar, versus zero for either raw checkpoint, but their values are wrong. Examples include ember=42 instead of 938, m1=40;m2=9;m3=4 instead of 7,63,67, a=7;b=6;c=0 instead of 7,11,4, and r=152 instead of 194. DRS therefore improved response-mode control without establishing the update rule. It also corrupted an unchanged field once.

Raw 300k does not improve this interview over raw 200k. It occasionally performs a local subexpression, such as 14*14-39=157, but drops the initial register value, repeats indefinitely, or emits templates. In RIV20 it first reaches 225 and then continues an uncontrolled update loop. Additional pretraining did not solve state transport or halting on this board.

Causal boundary and next test

The matched result supports a narrower controller/executor diagnosis:

1. Raw 200k contains some local arithmetic competence but lacks reliable packet serialization and instruction-conditioned halting.
2. DRS can impose a packet-like output grammar, consistent with its late residual digit channel, but does not reliably compute or consume the carried state.
3. Raw 300k provides no evidence that scale in pretraining steps alone repairs the missing state-update cycle.

The next descriptive interaction separates plain computation, gold-state serialization, model-state serialization, packet copying, one-step consumption, two-step consumption, and self-review. It may localize the failure more precisely, but it cannot promote a model or architecture. Promotion still requires frozen held-out autonomous multi-step gates with no host arithmetic, oracle schedule, residual patch, or result tape.