Alex Cheema 8f6726d6be Fix config.json download errors for image models (#1245) ...

## Motivation

When `get_shard_download_status()` runs, it iterates over all models in
`MODEL_CARDS` and calls `build_full_shard()` → `build_base_shard()` →
`ModelCard.from_hf()`. This unconditionally tried to download
`config.json` from HuggingFace, but image models (FLUX, Qwen-Image)
don't have a root-level config.json file, causing errors:

```
Error downloading shard: File not found: https://huggingface.co/black-forest-labs/FLUX.1-dev/resolve/main/config.json
Error downloading shard: File not found: https://huggingface.co/black-forest-labs/FLUX.1-schnell/resolve/main/config.json
Error downloading shard: File not found: https://huggingface.co/Qwen/Qwen-Image/resolve/main/config.json
Error downloading shard: File not found: https://huggingface.co/Qwen/Qwen-Image-Edit-2509/resolve/main/config.json
```

## Changes

### ModelCard.load() fix
- `build_base_shard()` now uses `ModelCard.load()` instead of
`ModelCard.from_hf()`
- `ModelCard.load()` iterates through `MODEL_CARDS.values()` to find a
match by `model_id`

### exo-bench fixes
- Use `name` field instead of `id` for model resolution
- Pass `full_model_id` to `/instance/previews` endpoint
- Make model name matching case-insensitive
- Update README example model name

## Why It Works

`MODEL_CARDS` uses short names as keys (e.g., `"flux1-schnell"`) but the
`model_id` values are HuggingFace paths (e.g.,
`"black-forest-labs/FLUX.1-schnell"`). When `ModelCard.load()` was
called with the HF path, it didn't match any key and fell back to
`from_hf()` which tried to download config.json.

The fix iterates through `MODEL_CARDS.values()` to find a match by
`model_id`, ensuring predefined models (including image models) use
their registry entries directly without network calls. A key lookup is
unnecessary since `load()` is always called with HF paths which don't
match the short-name keys.

## Test Plan

### Manual Testing
- Run exo and verify no more "Error downloading shard: File not found:
.../config.json" errors for image models
- Run exo-bench and verify model resolution works correctly

### Automated Testing
- `uv run basedpyright` - passes with 0 errors
- `uv run pytest` - all tests pass

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

2026-01-21 21:30:48 +00:00

..

exo_bench.py

Fix config.json download errors for image models (#1245)

2026-01-21 21:30:48 +00:00