Interactive

Playground

Paste a reasoning trace, pick a validated feature pack, see which SAE features fire per token and what mech-reward score the trace would earn.

Preview mode. The interactive backend will ship after Stage Gate 2 completes on Qwen3.6-35B-A3B. The feature IDs and labels below are real and pulled from qwen3.5-4b/reasoning_pack.json. Labels are illustrative; auto-interp via Neuronpedia is pending (72h SLA).

Prompt

Q: A store sells apples at $2 each. If you buy 7 apples, how much do you pay?
A: Let's think step by step. The price per apple is $2. Seven apples cost 7 × $2 = $14. So the total is $14.
#### 14

Model

Qwen/Qwen3.5-4B

Feature pack

qwen3.5-4b/reasoning_pack

Layer

residual post-L18

Backend online after G2.

R_mech per response

+1.62

-2.00+2.0