Alex Cheema 63b8e64715 Add model cards for Qwen3.6-35B-A3B variants (#1907) ...

## Motivation

`mlx-community` has just published the new **Qwen3.6-35B-A3B**
multimodal MoE family on HuggingFace. Without static model cards exo
doesn't surface these models in the dashboard picker or match its
placement / prefill logic, so users can't one-click launch them. This PR
adds cards for the three quants whose safetensors indexes are already
live on HF (4bit / 5bit / bf16).

## Changes

Three new TOML files in `resources/inference_model_cards/`:

- `mlx-community--Qwen3.6-35B-A3B-4bit.toml` (~19 GB)
- `mlx-community--Qwen3.6-35B-A3B-5bit.toml` (~23 GB)
- `mlx-community--Qwen3.6-35B-A3B-bf16.toml` (~65 GB)

All three share the same architectural fields (`n_layers = 40`,
`hidden_size = 2048`, `num_key_value_heads = 2`, `context_length =
262144`, capabilities `text, thinking, thinking_toggle, vision`,
`base_model = "Qwen3.6 35B A3B"`) — only `model_id`, `quantization`, and
`storage_size.in_bytes` differ between variants.

## Why It Works

- Qwen3.6-35B-A3B reuses the `qwen3_5_moe` architecture
(`Qwen3_5MoeForConditionalGeneration`) — the same one already wired into
exo's MLX runner at `src/exo/worker/engines/mlx/auto_parallel.py:47` via
`Qwen3_5MoeModel`. The architectural fields are taken verbatim from the
HF `config.json.text_config` and match the existing `Qwen3.5-35B-A3B-*`
cards.
- Storage sizes are the exact `metadata.total_size` read from each
variant's `model.safetensors.index.json` on HF, so download progress and
cluster-memory-fit checks are accurate.
- Vision support is flagged in `capabilities`; the `[vision]` block is
auto-detected by `ModelCard._autodetect_vision` from the upstream
`config.json`, so no hand-written vision config is required.
- The card loader (`_refresh_card_cache` in
`src/exo/shared/models/model_cards.py`) globs every `.toml` in
`resources/inference_model_cards/` on startup, so nothing else needs to
change — the `/models` endpoint and the dashboard picker pick them up
automatically.

The `mxfp4` / `mxfp8` / `nvfp4` variants are still uploading upstream
(index JSONs currently 404) and can be added in a follow-up PR once HF
completes.

## Test Plan

### Manual Testing

Hardware: MacBook Pro M4 Max, 48 GB unified memory.

- Built the dashboard, ran `uv run exo`, waited for the API to come up
on `http://localhost:52415`.
- `curl -s http://localhost:52415/models` returns the three new model
ids (`mlx-community/Qwen3.6-35B-A3B-{4bit,5bit,bf16}`) alongside
existing models.
- Opened the dashboard, clicked SELECT MODEL, typed "Qwen3.6" into the
search box. A single **"Qwen3.6 35B A3B"** group appears showing `3
variants (19GB-65GB)`. Expanding it lists the `4bit` / `5bit` / `bf16`
quants with sizes `19GB` / `23GB` / `65GB`, exactly as expected:

![Qwen3.6 35B A3B in model
picker](127119f703/qwen36-picker.png)

- Programmatically loaded each TOML via `ModelCard.load_from_path(...)`
and confirmed the parsed fields (layers / hidden / KV heads / context /
quant / base_model / caps / bytes) match what's written in the files.

### Automated Testing

No code paths were touched — these are pure TOML data files that plug
into the existing model-card loader. The existing pytest suite covers
TOML parsing and card serving; adding new TOMLs doesn't require new test
scaffolding. `uv run ruff check` and `nix fmt` are clean.

---------

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Co-authored-by: Ryuichi Leo Takashige <rl.takashige@gmail.com>

2026-04-16 23:25:26 +01:00

..

image_model_cards

Ciaran/image model listing (#1417)

2026-02-06 16:08:57 -08:00

inference_model_cards

Add model cards for Qwen3.6-35B-A3B variants (#1907)

2026-04-16 23:25:26 +01:00