Designs the SP14 chain on top of SP13 Layer B (HEAD 6657e5626):
1. Sub-project A — stability fixes (3 small bugs found in Smoke A)
- C51 atom-probability floor (ISV-driven from SP4 atom_pos_p99)
- aux_w setter clamp lift [0.05, 0.3] → [0.15, 1.5]
- Stagnation warmup gate at fold boundary
2. Sub-project B — the architectural piece (THIS spec)
- Forward wire: aux_softmax_diff per-bar into direction Q-head input
concat (in_dim+1, fingerprint bump, zero-init new column)
- Earned Gradient Flow pearl — adaptive ISV-driven gradient gating:
* Gate 1 (aux competence) — Schmitt-trigger hysteresis
* Gate 2 (Q-head disagreement) — NEW signal, EMA per-step argmax
mismatch
* ISV-adaptive sigmoid steepness (variance-driven k_aux, k_q)
* Per-epoch warmup ramp
* Anti-gradient-hacking circuit breaker (mesa-opt defense)
- 11 new ISV slots, 3 new GPU kernels, ~1060 LOC total
- HEALTH_DIAG pearl_egf_diag observability line
3. Sub-project C — Adaptive LR (deferred until A+B effects measured)
Motivation from Smoke A diagnostic:
- aux_dir_acc reached 0.61 (signal extraction works)
- val_win_rate stuck 45-48% (no path to action selection)
- WR-flat-while-aux-varies = Q-head directional weights frozen
- 1109 GRAD_CLIP_OUTLIER events (chronic; not noise)
Three parallel diagnostic agents triangulated three interlocking root
causes:
- Slot 375 has zero readers (the wire was scoped but never built)
- C51 raw grad reaches 9.5e6, saturates SP7 budget controller
- aux_w controller muzzled by SP11-era [0.05, 0.3] clamp
The Earned Gradient Flow pearl is a new application of the codebase's
pearl pattern: ISV-driven adaptive controller, but applied to backward-
pass gradient flow instead of forward-pass features. The wire is one-
way (stop-gradient) by default; co-training is earned by both:
(a) aux head demonstrating label competence, AND
(b) Q-head showing it's actually fighting aux signal (informative
disagreement above baseline).
Stability additions hardened against:
- Oscillation around target (Schmitt hysteresis)
- Numerical sigmoid saturation (argument clipping ±30)
- Stale variance EMAs across folds (state-reset-registry)
- Discontinuous warmup transitions (linear ramp)
- Mesa-optimization (gradient-hacking circuit breaker)
- Cold-start sentinel-state spurious gate openings (Pearl-A bootstrap)
Awaiting user review before invoking superpowers:writing-plans for
sub-project B (and a separate small plan for sub-project A).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
eaf4adcb98