Optional inputs not working

[constantinpape]

It seems that optional inputs are not working. See the example for running a SAM model with only box prompts below:

import bioimageio.core
import numpy as np

from bioimageio.core.digest_spec import create_sample_for_model
from bioimageio.spec.utils import download

model_description = bioimageio.core.load_description("diplomatic-bug/staged/1")

image = np.load(download(model_description.inputs[0].test_tensor).path)
embeddings = np.load(download(model_description.inputs[5].test_tensor).path)
box_prompts = np.load(download(model_description.inputs[1].test_tensor).path)

sample = create_sample_for_model(
    model=model_description, image=image, embeddings=embeddings, box_prompts=box_prompts
).as_single_block()
with bioimageio.core.create_prediction_pipeline(model_description) as pp:
    prediction = pp.predict_sample_block(sample)

This fails with:

Traceback (most recent call last):
  File "/home/pape/Work/my_projects/micro-sam/bio_mre.py", line 17, in <module>
    prediction = pp.predict_sample_block(sample)
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/pape/Work/bioimageio/core-bioimage-io-python/bioimageio/core/_prediction_pipeline.py", line 121, in predict_sample_block
    self.apply_preprocessing(sample_block)
  File "/home/pape/Work/bioimageio/core-bioimage-io-python/bioimageio/core/_prediction_pipeline.py", line 271, in apply_preprocessing
    op(sample)
  File "/home/pape/Work/bioimageio/core-bioimage-io-python/bioimageio/core/proc_ops.py", line 76, in __call__
    input_tensor = sample.members[self.input]
                   ~~~~~~~~~~~~~~^^^^^^^^^^^^
KeyError: 'point_prompts