# Explicit evaluation policy — draft implementation decision

Status: **DRAFT / NOT REGISTERED / NO SCIENTIFIC EXECUTION**.

This is a pre-outcome implementation choice by the coordinator for the existing
conditioning proposal. It does not change a frozen brain, eligibility-v2,
anatomical mask, odor identity, five-replicate matrix or scientific pass gate.
The AN engineering result remains separate; none of its 21 sources is edited.

## Probe timing and snapshots

- Every evaluation probe lasts 120 ms, with CS requests only in the half-open
  interval [0, 100 ms). The remaining 20 ms is a no-CS tail. This matches the
  proposed normal training CS duration; it is not the old L full-120-ms input.
- Normal, delayed and reversal curves use 0, 1, 2, 5, 10, 20 and 50 scheduled
  reinforcement opportunities. Intermediate snapshots are taken after the
  **complete epoch containing** that opportunity and its boundary update,
  not immediately at the US tick.
- Terminal checkpoint 50 includes all planned epochs, including trailing
  neutral or blank epochs. It is not an early snapshot chosen for response.
- Each snapshot executes both A and B evaluation inputs. No baseline-output
  deduplication is assumed. Repeated probes use the same independent evaluation
  input within a training replicate; they are paired observations, not new
  training replicates. There are still five independent training replicates
  per experimental cell and 80 independent A/B evaluation streams overall.
- Probe US and weight updates are disabled. A probe cannot update the training
  or retention trajectory. Acquisition/reversal/delayed start from the common
  declared reset state; retention forks the actual continuous saved state.

## Intermediate control alignment

For normal and delayed experiments, obtain the paired arm's complete ordered
CS prefix at the chosen epoch boundary. Match actual cue, occurrence, odor,
source random stream and full seed, not just the number of epochs.

- D=0, frozen, random reward and CS-only use that identical CS prefix.
- DAN-only uses the corresponding removed-CS/yoked epoch positions. It has
  **zero CS exposure**, not equal CS exposure; this is an intended control.
- Unpaired uses the earliest epoch boundary that has consumed the same ordered
  CS prefix, including US-only epochs already inserted before that boundary.
  Its terminal checkpoint includes the entire 150-epoch inventory.

Unpaired intermediate US counts and elapsed time can differ from paired.
Random-reward intermediate US counts can also differ. These differences must
be reported rather than called fully matched exposure. All complete terminal
inventories remain fixed by the original proposal. The terminal gate, not the
most favorable intermediate point, decides the result.

Reversal and no-reversal use each arm's own kth reinforcement epoch boundary.
Their intermediate CS prefixes may differ because their reinforced cues differ;
their complete 100-epoch inventories remain fixed. The signed readout always
keeps the original acquisition cue orientation and original pre baseline.

## Inventory, not approval

Under these choices the pure planner is expected to enumerate 9,440 probes
(1,132.8 biological seconds), in addition to the existing 10,760 seconds of
training, controls, reversal and continuous idle. This arithmetic is not a
measured wall-time or disk estimate and excludes engineering validation,
encoding, output, regressions and reserves. Test fixtures use synthetic masters;
none is adopted as a scientific master seed.

Before any scientific run, complete the actual input/state/delta file bindings,
exact event-to-eligibility update coordinator, implemented assay gates and a
finite resource plan. Register the protocol and bounded implementation check
before observing scientific outcomes. Only after those checks may the staged
acquisition suite run. A failed acquisition is sealed as failure; it must not
trigger more pairings, parameter changes, odor reselection or control removal.