exo-explore/exo · error · ValueError

Could not find inner transformer (embed_tokens) in {type(mod

Error message

Could not find inner transformer (embed_tokens) in {type(model).__name__}. Add a new pattern to _get_inner_model() for this architecture.

What it means

Error "Could not find inner transformer (embed_tokens) in {type(model).__name__}. Add a new pattern to _get_inner_model() for this architecture." thrown in exo-explore/exo.

Source

Thrown at src/exo/worker/engines/mlx/vision.py:635

            image_features = hidden_states

        # `create_vision_embeddings` expects a 2D (total_tokens, hidden) view,
        # but fixed-token-budget models (gemma4) return (n_images, tokens, hidden).
        if image_features.ndim == 3:
            image_features = image_features.reshape(-1, image_features.shape[-1])

        return image_features, n_tokens_per_image


def get_inner_model(model: nn.Module) -> Any:  # type: ignore
    for candidate in (
        getattr(model, "model", None),
        getattr(getattr(model, "language_model", None), "model", None),
    ):
        if candidate is not None and hasattr(candidate, "embed_tokens"):  # type: ignore
            return candidate  # type: ignore

    raise ValueError(
        f"Could not find inner transformer (embed_tokens) in {type(model).__name__}. "
        "Add a new pattern to _get_inner_model() for this architecture."
    )


def create_vision_embeddings(
    model: Model,
    prompt_tokens: mx.array,
    image_features: mx.array,
    image_token_id: int,
) -> mx.array:
    inner = get_inner_model(model)  # type: ignore
    embed_tokens = inner.embed_tokens  # type: ignore

    input_embeddings: mx.array = embed_tokens(prompt_tokens[None])  # type: ignore

    is_image: mx.array = mx.equal(prompt_tokens, image_token_id)
    n_placeholders = int(mx.sum(is_image).item())

View on GitHub (pinned to 21a54c5ea0)

When it happens

Trigger: Thrown at src/exo/worker/engines/mlx/vision.py:635 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of exo-explore/exo@21a54c5ea0 (2026-08-26). Data as JSON: /api/errors/2b919058a31e2162. Report an issue: GitHub.