Comfy-Org/ComfyUI · error · ValueError

Maximum {max_count} reference images are allowed.

Error message

Maximum {max_count} reference images are allowed.

What it means

Raised by _luma2_upload_image_refs (comfy_api_nodes/nodes_luma.py:695) when more reference images are supplied than the target Luma 2 / Ray endpoint allows (max_count, e.g. 9 for image refs). Note the check runs after every ref has already been uploaded, so the error also wastes upload time and bandwidth.

Source

Thrown at comfy_api_nodes/nodes_luma.py:695

            optional=True,
            tooltip=f"Up to {max_image_refs} reference images for style/content guidance.",
        ),
    ]


async def _luma2_upload_image_refs(
    cls: type[IO.ComfyNode],
    refs: dict | None,
    max_count: int,
) -> list[Luma2ImageRef] | None:
    if not refs:
        return None
    out: list[Luma2ImageRef] = []
    for key in refs:
        url = await upload_image_to_comfyapi(cls, refs[key])
        out.append(Luma2ImageRef(url=url))
    if len(out) > max_count:
        raise ValueError(f"Maximum {max_count} reference images are allowed.")
    return out or None


async def _luma2_submit_and_poll(
    cls: type[IO.ComfyNode],
    request: Luma2GenerationRequest,
    *,
    estimated_duration: int | None = None,
) -> Luma2Generation:
    """Submit a Luma Agents generation and poll until done; returns the completed generation."""
    initial = await sync_op(
        cls,
        ApiEndpoint(path="/proxy/luma_2/generations", method="POST"),
        response_model=Luma2Generation,
        data=request,
    )
    if not initial.id:
        raise RuntimeError("Luma API did not return a generation id.")

View on GitHub (pinned to 1c6d8d45b3)

Solutions

1. Count the chained image-ref nodes and reduce them to at most max_count (9 for Luma image refs).
2. Remove duplicate or lowest-value reference images from the chain.
3. If you hit this often, pre-validate len(refs) in your own wrapper node before executing.

MAX_REFS = 9
if refs and len(refs) > MAX_REFS:
    raise ValueError(f"Too many Luma image refs: {len(refs)} > {MAX_REFS}; trim the chain before executing")

When it happens

Trigger: Passing a refs dict (image_ref chain input) with more entries than max_count — e.g. 10+ Luma image-reference nodes chained into LumaImageNode2's image_ref input.

Common situations: Users chain many reference-image nodes believing more refs improve style fidelity; a workflow copied from a different node with a higher limit; duplicates accidentally added while editing a chain.

Related errors

• At least one of first_image and last_image requires an input
• 'manga' style requires a portrait aspect ratio ({allowed_man
• Looping is only available with 5s duration on Ray 3.2.
• Provide at least one of start_frame / end_frame.
• Looping is not available when an end_frame is set.

AI-assisted analysis of Comfy-Org/ComfyUI@1c6d8d45b3 (2026-08-14). Data as JSON: /api/errors/bfe403afbb748c6e. Report an issue: GitHub.