Skills

Boltz

Structure prediction for protein, nucleic-acid, and small-molecule complexes with...

Install

npx skills add aipoch/open-science --skill boltz -g -a claude-code -y
Repository
aipoch/open-science5.4k
Category
Design
Updated
3d ago
License
Apache-2.0
Context cost
Lightabout 1,134 tokens
Runs scripts
No, instructions only

What it does

Structure prediction for protein, nucleic-acid, and small-molecule complexes with Boltz-2 (Passaro & Wohlwend et al. 2025, github.com/jwohlwend/boltz). Reach for this skill to validate designed binders against a target, to co-fold a protein with a SMILES or CCD ligand, or to get an open-source AlphaFold3 alternative with optional binding-affinity prediction.

Boltz-2

Boltz-2 is the open-weights diffusion co-folder closest in surface to AlphaFold3: a YAML describing protein, DNA, RNA, and ligand chains in, mmCIF plus pTM/ipTM/pLDDT confidences out, with an optional small-molecule affinity head. Among our four co-fold skills it is the default for binder-validation campaigns, fully open MIT weights and the fastest sampler; pick chai1 when you want a second independent model for consensus, openfold3 when AF3-faithful settings matter, and esmfold2 when you can live without an MSA. Code and weights are MIT (PyPI boltz, github.com/jwohlwend/boltz).

Running it

# complex.yaml
version: 1
sequences:
  - protein:
      id: A
      sequence: MVTPEGNVSLVDESLLVGVTDEDRAVRS... # target
  - protein:
      id: B
      sequence: AIQRTPKIQVYSRHPAENG... # binder
  - ligand:
      id: L
      smiles: 'N[C@@H](Cc1ccc(O)cc1)C(=O)O' # or  ccd: SAH
boltz predict complex.yaml \
    --use_msa_server --out_dir out/ --recycling_steps 3 --diffusion_samples 5

Each protein chain needs an MSA; without one the run exits before the model loads. --use_msa_server queries api.colabfold.com (expect a 30, 90 s pause per chain) and is the right default unless you already have an .a3m to name under msa: in the YAML. Setting msa: empty forces single-sequence mode, that is an accuracy sacrifice, not a speed or memory optimization, because the MSA search runs on CPU before the GPU stage starts.

Per input the output lands at out/boltz_results_complex/predictions/complex/. Read confidence_complex_model_0.json first: iptm > 0.5 is the community pass line for an interface, complex_plddt > 0.7 for the fold itself, and confidence_score is the weighted aggregate the structures are ranked by. Structures themselves are complex_model_{0..N-1}.cif (or .pdb with --output_format pdb).

Affinity head

Read the whole SKILL.md on GitHub

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