Molfeat Molecular Featurization Hub
A guide skill for turning SMILES into 100+ ML-ready features with molfeat — ECFP, MACCS, descriptors and ChemBERTa embeddings.
Data & AnalyticsIntermediate★ 33,030⑂ 3,248AI score 8/10Last updated: Aug 9, 2026
What it does
- Walks through converting SMILES/RDKit molecules into numerical features for ML using the molfeat library.
- Separates the three layers clearly:
molfeat.calc(per-molecule calculators),molfeat.trans(scikit-learn compatible, parallel batch transformers), andmolfeat.trans.pretrained(deep embeddings like ChemBERTa, GIN, Graphormer). - Includes production tips:
n_jobs=-1parallelism, skipping invalid SMILES, saving/loading YAML featurizer state for reproducibility, chunked processing for big datasets, and npz-based embedding caching instead of pickle. - States constraints up front: Python 3.9–3.10, molfeat 0.11.0, datamol/PyTorch, optional extras, and MAP4 needing separate installation.
Who it's for
- Cheminformatics and drug-discovery researchers building QSAR/QSPR models or virtual screens.
- ML engineers training neural networks on molecular data.
- Data scientists benchmarking multiple featurizers to pick the best representation.
Example uses
- Featurize a CSV of compound SMILES into 2048-bit ECFP and feed it into a Random Forest activity model.
- Search the ModelStore for ChemBERTa-77M-MLM, load it, and extract 768-dim embeddings for transfer learning.
- Process a 100K+ molecule library in chunks with
ignore_errors=True, then export the exact featurizer config to YAML for reproducibility.
· · · Install guide · · ·
Try it now, no install
Paste this into Claude to use the skill without installing anything.
Read the instructions in this file and follow them to help me: https://raw.githubusercontent.com/K-Dense-AI/scientific-agent-skills/HEAD/skills/molfeat/SKILL.md What I want: (describe your task here)
If Claude can't open the link, open it yourself and paste the contents instead.
↓ If it works for you, download the ZIP below and install it. Then it runs on its own — no pasting each time.
Install in the Claude app (no terminal)
- Download the ZIP with the button below.
- In Claude, open Settings → Capabilities and turn on 'Code execution and file creation'. (one time)
- Go to Customize → Skills → + → 'Upload a skill' and upload the ZIP.
Install in Claude Code
Let Claude do it — paste this into Claude Code
Install the skill I found on Claude Skill Mart. Copy the skills/molfeat folder from the GitHub repo K-Dense-AI/scientific-agent-skills into my ~/.claude/skills/molfeat/. When it's done, tell me in one line what this skill can do.
Install with a command instead
git clone https://github.com/K-Dense-AI/scientific-agent-skills.git && mkdir -p ~/.claude/skills && cp -r scientific-agent-skills/skills/molfeat ~/.claude/skills/⚠ This is a third-party skill. Check the source repository before installing.
- Create a Python 3.9 or 3.10 virtual environment (molfeat 0.11.0 will not install on 3.11+).
- Install the library:
uv pip install "molfeat==0.11.0"(or plainpip install). Adduv pip install "molfeat[transformer]==0.11.0"if you need ChemBERTa/ChemGPT. - Clone the skill repo:
git clone https://github.com/K-Dense-AI/scientific-agent-skills.git - Copy the skill folder:
mkdir -p ~/.claude/skills && cp -r scientific-agent-skills/skills/molfeat ~/.claude/skills/ - Restart Claude Code, then ask something like "featurize these SMILES with ECFP" to trigger the skill.
- Verify the bundled
references/docs (available_featurizers.md, examples.md, api_reference.md) came along with the copy.
View source on GitHub ↗License: MIT