Session synthesis — c-csi-cross-geometry-scaleout (Phase 1 pilot)
Outcome: BLOCKED at the artefact-contract gate. Zero science runs launched. One preflight probe.
What the probe established (Step 2.5 dependency-chain gate)
A single cheap probe — exp-csi-static, floor resplan-1374-floor-0, n_agents=4, n_placements=8, seed=0, 2.4 GHz, where=local (run 01KX32AZAQTJ7G97JCXCA0NDCA) — cleanly separated infra health from the artefact contract:
- Infra gate CLEARED. PostGIS is reachable (
gis_stats: 2431 rows, 13 floors). Scene-staging viagis export-floorsucceeded, the floor exists, and the run passed the gate (gate_passed=true, exit 0, 6.3 s). The:5435connection-refused blocker that stopped sibling session01KWWJ0REM…on 2026-07-06 is resolved — Prerequisite #1 is met. - Artefact-contract gate FAILS. Stock
exp-csi-staticemits raw CSI only:csi.hdf5,links.parquet,fig_csi_vs_occupancy.png, a schema, and a 694-byte runner-telemetrymetrics.json. The run-recordmetricsfield is empty{}. There is no occupancy-estimation MAE, nocross_geometry.parquet(per floor×seed×N), no per-floor CV(N) table, no LOFO within/held-out breakdown, and noσ²_floor/σ²_seed.
Why this blocks all three criteria
Each criterion is a downstream occupancy-inference + cross-floor reduction (LOFO inflation ratio; nested variance decomposition; honest held-out baseline). sim_reduction_run's lofo_cv/multi_seed_ci aggregate per-run metrics, which are empty — and no occupancy-MAE column exists in any emitted artefact. Fanning out the 150-run sweep (10 floors × 5 occupancy × 3 seeds) would produce 150 un-reducible piles of raw CSI. No parameter change to exp-csi-static recovers this; it is structural.
Prerequisite to unblock (design-loop, not a re-dispatch)
The brief must declare a notebook: reduction harness (IP-087) that trains an occupancy estimator on the emitted CSI, computes per-run occupancy MAE, and writes cross_geometry.parquet + per-floor CV(N) + the LOFO within/held-out breakdown + σ²_floor/σ²_seed into metrics.json. Once that harness exists, Phase 1 (the pre-declared under-powered pilot, n=10 floors) can run to resolve the variance split, and Phase 2 (≥40 floors) can power the primary criterion. Criteria remain unresolved — blocked pre-corpus, not refuted.