> ## Documentation Index > Fetch the complete documentation index at: https://proto.evodesign.org/docs/llms.txt > Use this file to discover all available pages before exploring further. # Structure ipTM Score > Evaluate interface quality using predicted interface TM score
Structure ipTM Score
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Structure Prediction ยท 6 tools
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evo-design/proto-language/proto\_language/constraint/protein\_structure/structure\_confidence\_constraint.py
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Evaluate interface quality using predicted interface TM-score (ipTM). ipTM (interface predicted TM-score) specifically measures the quality of predicted inter-chain interfaces in multimeric complexes. Values range from 0.0 to 1.0, where higher values indicate better interface predictions. This constraint returns `1.0 - iptm`, so lower scores indicate better predicted interface quality. **Supported tools**: ESMFold2, AlphaFold3, Boltz2, Chai1, Protenix, AlphaFold2, AlphaFold2 binder (NOT ESMFold v1) ## API Reference
ConfigStructureBasedConstraintConfig Source
Base configuration for constraints using structure prediction tools. This base class standardizes how structure prediction tools and their configurations are specified across all structure-based constraints. Each tool has its own dedicated config field. Subclasses can optionally restrict which tools are supported by overriding the structure\_tool field with a narrower Literal type. Predictor: esmfold/esmfold2/alphafold3/boltz2/chai1/protenix/alphafold2/alphafold2\_binder. Options: `esmfold`, `esmfold2`, `alphafold3`, `boltz2`, `chai1`, `protenix`, `alphafold2`, `alphafold2_binder` Configuration for ESMFold structure prediction. Configuration for ESMFold2 structure prediction. Configuration for AlphaFold3 structure prediction. Configuration for Boltz2 structure prediction. Configuration for Chai1 structure prediction. Configuration for Protenix structure prediction. Configuration for the general AlphaFold2 multimer structure predictor. Configuration for the AF2 binder-design backend.
ReturnsConstraintOutput
Per-proposal score and `iptm` / `pdb_output` / `structure_tool` metadata; predicted Structure attaches to slot 0.
## Usage Programming a protein-protein binder with AF3: ```python python icon="python" theme={null} >>> from proto_language.core import Segment >>> target = Segment(length=200, sequence_type="protein") >>> binder = Segment(length=80, sequence_type="protein") >>> af3_iptm = Constraint( ... inputs=[target, binder], ... function=structure_iptm_constraint, ... function_config={ ... "structure_tool": "alphafold3", ... "alphafold3_config": {"seeds": [0, 1], "use_msa": True}, ... }, ... ) ``` Programming a protein-DNA binder with Boltz2: ```python python icon="python" theme={null} >>> from proto_language.core import Segment >>> protein = Segment(length=100, sequence_type="protein") >>> aptamer = Segment(length=20, sequence_type="dna") >>> boltz_iptm = Constraint( ... inputs=[protein, aptamer], ... function=structure_iptm_constraint, ... function_config={ ... "structure_tool": "boltz2", ... "boltz2_config": {"use_msa_server": True}, ... }, ... ) ``` ## Metadata | Property | Value | | --------------- | --------------------------------- | | Key | `structure-iptm` | | Function | `structure_iptm_constraint` | | Category | `protein_structure` | | Mode | `discrete` | | Uses GPU | `True` | | Supported Types | `protein`, `rna`, `dna`, `ligand` |