molclaw-mol-similarity

Compute Tanimoto similarities and shared fragment counts between SMILES using Morgan fingerprints.

28|2|Updated Mar 31, 2026
One-click install
npx skills add https://github.com/InternScience/MolClaw --skill molclaw-mol-similarity
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: molclaw-mol-similarity
Source: https://github.com/InternScience/MolClaw/tree/main/skills/L1_tools/molclaw-mol-similarity
Command: npx skills add https://github.com/InternScience/MolClaw --skill molclaw-mol-similarity

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Rapidly quantify how similar candidate small molecules are to a target molecule by computing Tanimoto similarity scores and counting shared structural fragments using Morgan fingerprints, enabling data-driven prioritization in screening and hit triage.

Core Features & Use Cases

  • Tanimoto similarity calculation between a target SMILES and a list of candidate SMILES using configurable Morgan fingerprint radius and bit size.
  • Shared fragment counting that returns the number of common structural fragments per candidate to support scaffold analysis and diversity filtering.
  • Use Cases: prioritize virtual screening hits by similarity, cluster compounds for lead selection, or compute similarity metrics for downstream ML models.

Quick Start

Compare the target SMILES CC(=O)Oc1ccccc1C(=O)O against a list of candidate SMILES to compute Tanimoto similarity scores and shared fragment counts with a Morgan radius of 2.

Frequently Asked Questions about molclaw-mol-similarity

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I compute Tanimoto similarity for virtual screening hits using SMILES strings?

To compute Tanimoto similarity for virtual screening, you provide a target SMILES string and a list of candidate SMILES strings. The Skill calculates Morgan fingerprints for each molecule and returns per-candidate Tanimoto similarity scores to rank your screening hits.

Can I adjust the Morgan fingerprint radius and bit size for molecular similarity calculations?

Yes, you can configure both the Morgan fingerprint radius and nBits parameters for molecular similarity calculations. Adjusting these settings allows you to control the granularity of the structural features captured, directly impacting the resulting Tanimoto similarity scores and fragment counts.

What is the best way to count shared structural fragments between a target molecule and candidates?

The best way to count shared structural fragments is by using Morgan fingerprints to identify common substructures. The Skill compares a target SMILES against candidate SMILES and returns the exact number of shared structural fragments per candidate for scaffold analysis and diversity filtering.

Does this Tanimoto similarity tool work for clustering compounds in drug discovery workflows?

Yes, this Tanimoto similarity tool works for clustering compounds in drug discovery workflows. By computing pairwise similarity scores and shared fragment counts across lists of SMILES strings, you can group similar molecules for lead selection and downstream hit triage analysis.

How do I prioritize hit triage candidates using molecular similarity metrics?

You prioritize hit triage candidates by ranking them based on Tanimoto similarity scores and shared structural fragment counts relative to a target SMILES. Higher scores indicate greater structural similarity, allowing data-driven prioritization of small-molecule screening results.

Why use Morgan fingerprints for small-molecule screening instead of other molecular representations?

Morgan fingerprints are used for small-molecule screening because they efficiently encode local structural environments into bit vectors. This enables rapid Tanimoto similarity calculations and shared fragment counting across large candidate SMILES lists for hit triage and clustering.