A live inspector for language models: every layer's activity — norms, heads, router flow, logit lens, attention, residual trajectories — streamed into your browser as the model generates. OpenAI-compatible, testable, honest. The animation behind this card is the actual visualization, running on mock data.
Every layer's residual decoded as if the network stopped there. Dots mark where the prediction changes with depth — red where it settles on the token actually emitted. Settle depth ≈ per-token difficulty.
Each token's hidden state as a point in a fixed random 3D basis, connected in generation order — blue dotted trace is the full prompt context. Loops = repeated structure; outliers = attention sinks. Drag-rotate, per-layer minimap in the real app.
Select any token and see where it looked: top attention sources (mean over heads) drawn as arcs over the token strip, with per-token uncertainty (entropy + margin) riding on every frame.
Point any SDK or agent
framework at http://localhost:8080/v1 — zero code change
and every request is fully instrumented, recorded and replayable.
Spec-compliant
tool_calls round-trips (LFM2 pythonic + JSON parsing) and
image content parts — vision-language chats are hooked like any
other.
The curator records every run and gates CI: internals checks (finite norms, settle depth, uncertainty, attention focus) plus tool-reasoning suites — should-call / abstain / arguments / grounded chains.
Curated models on WebGPU via transformers.js — and an observable-ONNX export that graph-surgeries residual streams into declared outputs, so serverless runs still show real per-layer activity.
| capability | server | browser | browser·observable |
|---|---|---|---|
| chat + top-k predictions | ✓ | ✓ | ✓ |
| tool calling · multimodal | ✓ | — | — |
| norm heatmaps · heads · lens · arcs | ✓ | — | resid |
| residual trajectory + context | ✓ | — | ✓ |
| curator recording | ✓ | — | — |
Works with any HF causal LM — hybrid conv/SSM, MoE and vision-language models are first-class. Apple-silicon (mps), CUDA and CPU devices.
product six-pager (PDF) · the vault (architecture & flow graphs, protocol, engines) · CONTRIBUTING · AGENTS.md keeps humans and AI agents honest about docs.
suite cases & curator checks (no ML needed) → curated browser engines → dashboard views for attention/entropy → observable-export coverage → hooks for new architectures.
Honest pixels (never render unmeasured data) · every PR keeps the vault diagrams true · suites green before merge · MIT licensed.