SRT Adapter — Qwen3-235B-A22B (Phase-A, read-only)

A Semiotic-Reflexive Transformer (SRT) side-channel adapter trained on a frozen Qwen3-235B-A22B-FP8 backbone. This is a Phase-A, read-only checkpoint: the 235B backbone runs forward-only under no_grad, and only the ~15.9M SRT head parameters are trained on detached residual-stream taps. None of the backbone weights are modified.

It is the first SRT adapter ported to a frontier-scale (235B / 22B-active MoE) host, demonstrating that the SRT read-out heads transfer across backbone scale and architecture (dense Qwen2.5-7B → Qwen3 MoE 94-layer).

What it does

The adapter exposes read-only introspection signals over the frozen backbone's residual stream:

• Divergence — per-layer reflexive divergence taps (MAH @ layers 23/46/69).
• Regime — a calibrated subcritical/supercritical classifier (BEN head).
• r̂ (reflexivity) — a continuous bifurcation-magnitude estimate.
• Community — a 64-d discourse-community embedding (head @ layer 13).

Held-out evaluation (3,000 rows, read-only)

Measured with scripts/phaseA_probe.py on a held-out validation split, sharded across 8 GPUs.

(523,391 regime tokens; supercritical base rate 0.945. Divergence taps verified non-degenerate.)

Note: r̂ ranks well but under-predicts magnitude (pred mean 0.58 vs true 1.04); a scalar affine recalibration roughly halves the MAE.

Architecture

• Backbone: Qwen/Qwen3-235B-A22B-FP8 (frozen, fine-grained FP8 e4m3, 94 layers, d=4096, 128 experts / 8 active).
• Hook layers: MAH @ [23, 46, 69], inject @ [46, 69], community @ 13.
• Trainable: 15,907,139 params (heads only). Frozen: 235,107,904,512.
• The backbone is run through a manual, device-aware layer loop so the SRT taps and (optional) injections sit between layers; the MoE block is untouched.

Training

• Mode: Phase-A read-only (--read-only), backbone under no_grad.
• Warm-started from a bs=16 step-2000 checkpoint, then bs=128 for 2000 steps.
• Best validation at step 1750 (bif 0.0666; ~33% better than the bs=16 baseline of 0.0999).
• Corpus: 1M-row phase-1 mixed Reddit/discourse corpus, NLI-style labels.

Files

• best_adapter.pt — the step-1750 validation-best adapter weights (41 tensors).
• config.json — full SRTConfig (backbone id, hook layers, head dims).
• qwen3_235b_phaseA_probe.json — held-out probe metrics + reliability bins.

Usage

from srt.adapter import SRTAdapter
from srt.config import SRTConfig

config = SRTConfig(backbone_id="Qwen/Qwen3-235B-A22B-FP8", backbone_dtype="bfloat16")
model = SRTAdapter(config, device_map="auto")   # shards the 235B backbone
model.set_head_device("cuda:0")
model.load_adapter("best_adapter.pt")
model.eval()

out = model(input_ids=ids, attention_mask=mask, read_only=True)
# out.ben_output.regime_logits  -> (B,T,2) regime
# out.ben_output.r_hat          -> (B,T)   reflexivity
# out.community_output.encoded  -> (B,d)   community embedding
# out.divergences               -> per-layer divergence taps

Requires the SRT code from https://github.com/space-bacon/SRT (manual device-aware layer loop, transformers==4.53.3, torch ≥ 2.7 + cu128 for Blackwell). The backbone is frozen, so serving on the FP8 checkpoint matches the FP8 taps the heads were trained on.

Scope and honesty

These are observational read-outs of internal state. The regime head is well-calibrated and discriminative on held-out data, but this adapter is not a validated hallucination detector. The closed-loop FiLM inject path (Phase-B) is not trained in this checkpoint.

Source: https://github.com/space-bacon/SRT