[Bug]`int()` parsing failure when component contains `P` suffix during RFD3 input parsing

[seacid]

Bug: int() parsing failure when component contains P suffix during RFD3 input parsing

Description

During RFD3 inference, the input parser fails when processing the generated design length component.

The parser function accumulate_components() expects each non-motif component to be an integer value and directly converts the component using:

n = int(component)

However, the component list generated by get_design_pattern_with_constraints() contains a string value with a protein type suffix:

component = "80P"

This value cannot be converted by Python's int() function:

int("80P")

resulting in:

ValueError: invalid literal for int() with base 10: '80P'

---

Reproduction

Input specification:

{
    "test_L80": {
        "input": "/content/L-homoserine_seed.pdb",
        "length": "80-80",
        "ligand": "LIG",
        "dialect": 2
    }
}

Component expansion result:

get_design_pattern_with_constraints(
    "80-80",
    length="80-80"
)

# returns:
['80P']

The generated component is then passed into:

accumulate_components()

where the parser assumes:

component == "80"

but receives:

component == "80P"

---

Expected behavior

The component format passed to accumulate_components() should match the parser expectation.

Either:

1. The component generator should return an integer-compatible value:

80

or:

2. The parser should explicitly support typed component strings:

80P

and extract the numeric length before integer conversion.

---

Affected code

File:

rfd3/src/rfd3/inference/input_parsing.py

Function:

accumulate_components()

Current logic:

else:
    n = int(component)

The current implementation assumes that all non-alphabetic components are pure integers.

---

Environment

Repository:

foundry_RFdiffusion3

Related modules:

foundry.utils.components
rfd3.inference.input_parsing

Model initialization and checkpoint loading complete successfully. The failure occurs only during input component parsing.