K-Dense-AI/scientific-agent-skills/skills/rdkit/SKILL.md
rdkit
Cheminformatics toolkit for fine-grained molecular control. SMILES/SDF parsing, descriptors (MW, LogP, TPSA), fingerprints, substructure search, 2D/3D generation, similarity, reactions. For standard workflows with simpler interface, use datamol (wrapper around RDKit). Use rdkit for advanced control, custom sanitization, specialized algorithms.
- Source repository stars
- 31,966
- Declared platforms
- 0
- Static risk flags
- 0
- Last source update
- 2026-07-28
- Source checked
- 2026-07-28
Decision brief
What it does—and where it fits
Cheminformatics toolkit for fine-grained molecular control. SMILES/SDF parsing, descriptors (MW, LogP, TPSA), fingerprints, substructure search, 2D/3D generation, similarity, reactions.
Not for
- Forgetting to check for None: Always validate molecules after parsing
- Sanitization failures: Use DetectChemistryProblems() to debug
Compatibility matrix
Platform support, with evidence labels
| Platform | Status | Evidence | What to check |
|---|---|---|---|
| Codex | Not declared | No explicit evidence | Portability before use |
| Claude Code | Not declared | No explicit evidence | Portability before use |
| Cursor | Not declared | No explicit evidence | Portability before use |
| Gemini CLI | Not declared | No explicit evidence | Portability before use |
Installation
Inspect first. Install second.
The source command is displayed only when detected. A safe inspection prompt is always available so your agent can explain every action before execution.
npx skills add https://github.com/K-Dense-AI/scientific-agent-skills --skill "skills/rdkit"Inspect the Agent Skill "rdkit" from https://github.com/K-Dense-AI/scientific-agent-skills/blob/e7ac42510774624f327003c95b6650e2883bc01d/skills/rdkit/SKILL.md at commit e7ac42510774624f327003c95b6650e2883bc01d. List every install step, command, network request, credential, file read/write, external action, and rollback step. Explain whether it fits my task. Do not install or execute anything until I approve.
Workflow
What the source asks the agent to do
- 01
Installation and Setup
Use uv when installing into an existing Python environment:
Use uv when installing into an existing Python environment:For reproducible chemistry environments, especially when mixing compiled scientific packages, conda-forge remains the upstream recommendation:Avoid installing both conda rdkit and PyPI rdkit/rdkit-pypi into the same environment unless you are deliberately debugging packaging behavior. Mixed installs can make it unclear which binary extension is being imported. - 02
Core Capabilities
Twelve capability areas, each with worked code, are documented in references/corecapabilities.md:
Twelve capability areas, each with worked code, are documented in references/corecapabilities.md:Worked workflows and the performance, thread-safety, and version-sensitivity notes are in references/workflowsandbestpractices.md.Prefer portable exchange formats (SMILES, SDF) for shared data; for local caches RDKit's binary molecule representation avoids generic pickle. - 03
Common Pitfalls
1. Forgetting to check for None: Always validate molecules after parsing 2. Sanitization failures: Use DetectChemistryProblems() to debug 3. Missing hydrogens: Use AddHs() when calculating properties that depend on hydrogen 4. 2D vs 3D: Generate appropriate coordinates before vi…
Forgetting to check for None: Always validate molecules after parsingSanitization failures: Use DetectChemistryProblems() to debugMissing hydrogens: Use AddHs() when calculating properties that depend on hydrogen - 04
references/
This skill includes detailed API reference documentation:
apireference.md - Comprehensive listing of RDKit modules, functions, and classes organized by functionalitydescriptorsreference.md - Complete list of available molecular descriptors with descriptionssmartspatterns.md - Common SMARTS patterns for functional groups and structural features - 05
scripts/
Example scripts for common RDKit workflows:
molecularproperties.py - Calculate comprehensive molecular properties and descriptorssimilaritysearch.py - Perform fingerprint-based similarity screeningsubstructurefilter.py - Filter molecules by substructure patterns
Permission review
Static risk signals and limitations
No configured static risk pattern was detected
This is not proof of safety. Runtime behavior, indirect dependencies, and hidden external systems are outside the static scan.
Evidence record
Why each signal appears
| Signal | Value | Evidence type | Meaning |
|---|---|---|---|
| Quality score | 79/100 | Computed | Documentation, specificity, maintenance, and trust rules |
| Repository stars | 31,966 | Source | Repository attention, not individual Skill quality |
| Compatibility | 0 platforms | Source | Declared in the catalog source record |
| Usage guide | automated source guide | Editorial | Generated or reviewed according to the visible evidence level |
Pinned source
Provenance and original SKILL.md
- Repository
- K-Dense-AI/scientific-agent-skills
- Skill path
- skills/rdkit/SKILL.md
- Commit
- e7ac42510774624f327003c95b6650e2883bc01d
- License
- MIT
- Collected
- 2026-07-28
- Default branch
- main
View the original SKILL.md
RDKit Cheminformatics Toolkit
Overview
RDKit is a comprehensive cheminformatics library providing Python APIs for molecular analysis and manipulation. This skill provides guidance for reading/writing molecular structures, calculating descriptors, fingerprinting, substructure searching, chemical reactions, 2D/3D coordinate generation, and molecular visualization. Use this skill for drug discovery, computational chemistry, and cheminformatics research tasks.
Current baseline (checked 2026-06-07): RDKit 2026.03.3 is the latest GitHub/PyPI release (rdkit 2026.3.3 on PyPI). Official installation docs continue to recommend conda-forge for most users, while cross-platform PyPI wheels are published under the rdkit package name. rdkit-pypi is the old PyPI package name and should only appear when maintaining legacy environments.
Installation and Setup
Use uv when installing into an existing Python environment:
uv pip install rdkit
For reproducible chemistry environments, especially when mixing compiled scientific packages, conda-forge remains the upstream recommendation:
conda create -c conda-forge -n my-rdkit-env rdkit
conda activate my-rdkit-env
Avoid installing both conda rdkit and PyPI rdkit/rdkit-pypi into the same environment unless you are deliberately debugging packaging behavior. Mixed installs can make it unclear which binary extension is being imported.
Core Capabilities
Twelve capability areas, each with worked code, are documented in references/core_capabilities.md:
| # | Area | Covers |
|---|---|---|
| 1 | Molecular I/O and creation | SMILES, MOL files and blocks, InChI, SDF and SMILES suppliers, multithreaded reading, writers |
| 2 | Sanitization and validation | disabling automatic sanitization, manual and partial sanitization, detecting problems first |
| 3 | Analysis and properties | atom and bond iteration, ring information and SSSR, chirality and stereochemistry, fragments |
| 4 | Descriptors | MW, LogP, TPSA, H-bond donors/acceptors, rotatable bonds, aromatic rings, bulk calculation, drug-likeness |
| 5 | Fingerprints and similarity | topological, Morgan/ECFP via rdFingerprintGenerator, MACCS, atom pair, torsion, Avalon; Tanimoto and other metrics; Butina clustering |
| 6 | Substructure searching | SMARTS queries, match retrieval, and a library of common patterns |
| 7 | Chemical reactions | reaction SMARTS, applying reactions, reaction fingerprints |
| 8 | 2D and 3D coordinates | depiction, template alignment, ETKDG embedding, force-field optimization, RMSD, constrained embedding |
| 9 | Visualization | single and grid images, substructure highlighting, custom drawer options, Jupyter integration, fingerprint bit environments |
| 10 | Molecular modification | explicit hydrogens, Kekulization, aromaticity, substructure replacement, charge neutralization |
| 11 | Hashes and standardization | Murcko scaffold and canonical hashes, regioisomer hashes, randomized SMILES for augmentation |
| 12 | Pharmacophore and 3D features | feature factories and feature extraction |
Worked workflows and the performance, thread-safety, and version-sensitivity notes are in references/workflows_and_best_practices.md.
Prefer portable exchange formats (SMILES, SDF) for shared data; for local caches RDKit's binary molecule representation avoids generic pickle.
Common Pitfalls
- Forgetting to check for None: Always validate molecules after parsing
- Sanitization failures: Use
DetectChemistryProblems()to debug - Missing hydrogens: Use
AddHs()when calculating properties that depend on hydrogen - 2D vs 3D: Generate appropriate coordinates before visualization or 3D analysis
- SMARTS matching rules: Remember that unspecified properties match anything
- Thread safety with MolSuppliers: Don't share supplier objects across threads
Resources
references/
This skill includes detailed API reference documentation:
api_reference.md- Comprehensive listing of RDKit modules, functions, and classes organized by functionalitydescriptors_reference.md- Complete list of available molecular descriptors with descriptionssmarts_patterns.md- Common SMARTS patterns for functional groups and structural features
Load these references when needing specific API details, parameter information, or pattern examples.
Only the files listed in references/ and scripts/ are bundled local resources. Names such as rdkit, datamol, scipy, and sklearn refer to installable Python packages, not local files in this skill.
scripts/
Example scripts for common RDKit workflows:
molecular_properties.py- Calculate comprehensive molecular properties and descriptorssimilarity_search.py- Perform fingerprint-based similarity screeningsubstructure_filter.py- Filter molecules by substructure patterns
These scripts can be executed directly or used as templates for custom workflows.