Small-Molecule Design Tools
This skill routes small-molecule design tasks to suitable open or publicly
documented tools. It directs the agent to a focused reference and keeps the
applicable license and data terms visible during tool selection.
Use the skill in two passes:
- Identify the physical or chemical task.
- Open the matching reference file before recommending tools or writing code.
For commercial or product-facing work, also open
references/licensing-and-data.md. Code,
weights, data, and base-model terms often differ for the same upstream project.
Reference Map
Start with references/tool-matrix.md when the user
wants a broad comparison across categories.
Makeability and synthesis:
- references/synthesizable-generation.md:
makeable molecule generation, analogs, make-on-demand libraries, and route
co-generation.
- references/molecular-generation.md:
general molecule generators where validity matters more than synthesis route
guarantees.
- references/retrosynthesis-planning.md:
multi-step route planners and validators such as AiZynthFinder, RENKIN,
ASKCOS, Syntheseus, and SynPlanner.
- references/singlestep-retrosynthesis.md:
one-step precursor prediction with ReactionT5v2, RXNGraphormer, GDiffRetro,
RetroDiT, ConRetroBert, TempRe, and related models.
- references/agentic-retrosynthesis.md:
LLM and agent-assisted synthesis planners, including RetroAgent.
- references/forward-and-reaction-modeling.md:
forward reaction and mechanism prediction.
- references/template-and-rule-infrastructure.md:
reaction templates, SMARTS rules, RDChiral, rxnutils, and SynTemp.
- references/synthesizability-scoring.md:
makeability scoring and route consistency checks.
Target-based design:
- references/protein-structure-prediction.md:
receptor structure prediction and preparation.
- references/docking-and-cofolding.md:
classical docking, learned docking, protein-ligand co-folding, and pose
scoring.
- references/binding-affinity-and-fep.md:
ML affinity, OpenFE, OpenMM, endpoint methods, and free-energy workflows.
- references/property-and-qsar-prediction.md:
QSAR, activity, property, and active-learning screens.
- references/admet-prediction.md:
ADMET, hERG, BBB, CYP, and locally runnable predictors.
- references/target-and-selectivity-prediction.md:
off-target, selectivity, shape, and pharmacophore tools.
- references/structure-based-generation.md:
pocket-conditioned generation and pocket detection.
Cross-cutting:
- references/agentic-drug-design.md:
agent frameworks that orchestrate generation, scoring, ADMET, and affinity
tools.
- references/chemical-language-models.md:
chemistry language models and multimodal chemistry models.
- references/licensing-and-data.md:
license layers, Enamine terms, PDB/PDBBind notes, ChEMBL/TDC data terms, and
terms-review checklist.
- references/worked-example-kras-glue.md:
public worked example on daraxonrasib, KRAS, and CypA using PDB 9BG6.
- references/watchlist.md:
tools with missing code, missing weights, unclear license terms, or early-stage
releases.
Routing Rules
Use the user's actual task to choose the first reference:
| User task |
Start with |
| Generate makeable analogs of a hit |
synthesizable-generation.md |
| Project a molecule into synthesizable space |
synthesizable-generation.md |
| Generate valid molecules for exploration |
molecular-generation.md |
| Plan a route to a known target molecule |
retrosynthesis-planning.md |
| Predict one reaction step |
singlestep-retrosynthesis.md |
| Check whether a proposed reaction route is plausible |
forward-and-reaction-modeling.md, then synthesizability-scoring.md |
| Prepare or predict a receptor structure |
protein-structure-prediction.md |
| Dock a ligand into a known structure |
docking-and-cofolding.md |
| Co-fold a protein-ligand complex from sequence and ligand |
docking-and-cofolding.md |
| Estimate binding affinity |
binding-affinity-and-fep.md |
| Build a QSAR or property model |
property-and-qsar-prediction.md |
| Screen ADMET risk |
admet-prediction.md |
| Screen off-target or selectivity risk |
target-and-selectivity-prediction.md |
| Generate molecules into a pocket |
structure-based-generation.md |
| Orchestrate a full agentic loop |
agentic-drug-design.md, then the category references it calls |
| Check a tool's terms for product-facing work |
licensing-and-data.md, then the tool card |
First Picks
Use these as starting points, then read the relevant reference file for details:
| Need |
First pick |
| Synthesizable-space projection |
PrexSyn |
| Training-free analog generation |
Review SynTwins after confirming its code terms; the repository has no LICENSE file |
| 3D molecule and route co-generation |
Review SynCoGen; its weights and data are labeled MIT, but its code has no stated license |
| Make-on-demand design over Enamine-style libraries |
SyntheMol; APEX has no stated repository or artifact license |
| General de novo molecule generation |
GenMol after checking its separate model terms |
| Multi-step route planning |
AiZynthFinder for a local baseline; RENKIN for route validation; ASKCOS when broader planning and conditions are needed |
| One-step retrosynthesis |
ReactionT5v2 |
| LLM-assisted route planning |
DeepRetro, RetroAgent, or Synthelite, followed by round-trip checks |
| Reaction templates and data cleanup |
RDChiral or rdchiral_plus with rxnutils |
| ML affinity with MIT-licensed code and weights |
Boltz-2 |
| Protein-ligand co-folding |
OpenBind-0, Boltz-1, Chai-1, or Umol after checking the terms for the selected release |
| Learned docking into a known pocket |
DiffDock-L or Uni-Mol Docking v2 |
| Classical CPU docking |
AutoDock Vina |
| Physics-based relative free energy |
OpenFE |
| QSAR from ChEMBL-style data |
Chemprop or DeepChem |
| Local ADMET triage |
ADMET-AI |
| Broad off-target scan |
ChEMBL multitask model plus ESP-Sim where shape overlap matters |
| Pocket-conditioned generation |
REINVENT 4, DiffSBDD, PILOT, Pocket2Mol, or TargetDiff, followed by makeability checks |
Operating Notes
- Read source licenses directly. README badges and paper text can disagree with
the repository license, model-card license, or dataset terms.
- Check code, weights, data, and base-model terms separately. For an LLM
fine-tune, record both the project terms and the original base-model terms.
- Treat docking and co-folding confidence scores as pose-confidence signals.
Binding-affinity estimates require an affinity model or a free-energy method.
- For molecular glues, degraders, covalent binders, and macrocycles, choose tools
that model the complete mechanism. A single-pocket docking workflow omits
important components of these systems.
- When an experimental ternary structure exists, perturb and score that
structure before asking a co-folding model to predict it again.
- Pair pocket-conditioned generators with a makeability step. Most structure-
based generators do not guarantee a synthesis route.
- Re-check upstream repositories for pre-1.0 models and entries with recent
verification dates.
Pipeline Pattern
A full design loop crosses both layers:
- Get or predict the receptor structure.
- Generate, dock, co-fold, or score candidate molecules for the target.
- Filter for affinity, QSAR, ADMET, and selectivity.
- Project survivors into synthesizable space.
- Plan or validate routes.
- Re-check licenses and data terms before deployment.
Load the detailed reference file for install commands, model weights, benchmark
context, GPU needs, and documented caveats.
1---2name: small-molecule-design-tools3description: Use when choosing or applying open or publicly documented small-molecule design, synthesis-planning, docking, binding-affinity, QSAR, ADMET, pocket-finding, or ligand-generation tools for work with public or synthetic data.4---56# Small-Molecule Design Tools78This skill routes small-molecule design tasks to suitable open or publicly9documented tools. It directs the agent to a focused reference and keeps the10applicable license and data terms visible during tool selection.1112Use the skill in two passes:13141. Identify the physical or chemical task.152. Open the matching reference file before recommending tools or writing code.1617For commercial or product-facing work, also open18[references/licensing-and-data.md](references/licensing-and-data.md). Code,19weights, data, and base-model terms often differ for the same upstream project.2021## Reference Map2223Start with [references/tool-matrix.md](references/tool-matrix.md) when the user24wants a broad comparison across categories.2526Makeability and synthesis:2728- [references/synthesizable-generation.md](references/synthesizable-generation.md):29 makeable molecule generation, analogs, make-on-demand libraries, and route30 co-generation.31- [references/molecular-generation.md](references/molecular-generation.md):32 general molecule generators where validity matters more than synthesis route33 guarantees.34- [references/retrosynthesis-planning.md](references/retrosynthesis-planning.md):35 multi-step route planners and validators such as AiZynthFinder, RENKIN,36 ASKCOS, Syntheseus, and SynPlanner.37- [references/singlestep-retrosynthesis.md](references/singlestep-retrosynthesis.md):38 one-step precursor prediction with ReactionT5v2, RXNGraphormer, GDiffRetro,39 RetroDiT, ConRetroBert, TempRe, and related models.40- [references/agentic-retrosynthesis.md](references/agentic-retrosynthesis.md):41 LLM and agent-assisted synthesis planners, including RetroAgent.42- [references/forward-and-reaction-modeling.md](references/forward-and-reaction-modeling.md):43 forward reaction and mechanism prediction.44- [references/template-and-rule-infrastructure.md](references/template-and-rule-infrastructure.md):45 reaction templates, SMARTS rules, RDChiral, rxnutils, and SynTemp.46- [references/synthesizability-scoring.md](references/synthesizability-scoring.md):47 makeability scoring and route consistency checks.4849Target-based design:5051- [references/protein-structure-prediction.md](references/protein-structure-prediction.md):52 receptor structure prediction and preparation.53- [references/docking-and-cofolding.md](references/docking-and-cofolding.md):54 classical docking, learned docking, protein-ligand co-folding, and pose55 scoring.56- [references/binding-affinity-and-fep.md](references/binding-affinity-and-fep.md):57 ML affinity, OpenFE, OpenMM, endpoint methods, and free-energy workflows.58- [references/property-and-qsar-prediction.md](references/property-and-qsar-prediction.md):59 QSAR, activity, property, and active-learning screens.60- [references/admet-prediction.md](references/admet-prediction.md):61 ADMET, hERG, BBB, CYP, and locally runnable predictors.62- [references/target-and-selectivity-prediction.md](references/target-and-selectivity-prediction.md):63 off-target, selectivity, shape, and pharmacophore tools.64- [references/structure-based-generation.md](references/structure-based-generation.md):65 pocket-conditioned generation and pocket detection.6667Cross-cutting:6869- [references/agentic-drug-design.md](references/agentic-drug-design.md):70 agent frameworks that orchestrate generation, scoring, ADMET, and affinity71 tools.72- [references/chemical-language-models.md](references/chemical-language-models.md):73 chemistry language models and multimodal chemistry models.74- [references/licensing-and-data.md](references/licensing-and-data.md):75 license layers, Enamine terms, PDB/PDBBind notes, ChEMBL/TDC data terms, and76 terms-review checklist.77- [references/worked-example-kras-glue.md](references/worked-example-kras-glue.md):78 public worked example on daraxonrasib, KRAS, and CypA using PDB 9BG6.79- [references/watchlist.md](references/watchlist.md):80 tools with missing code, missing weights, unclear license terms, or early-stage81 releases.8283## Routing Rules8485Use the user's actual task to choose the first reference:8687| User task | Start with |88|---|---|89| Generate makeable analogs of a hit | `synthesizable-generation.md` |90| Project a molecule into synthesizable space | `synthesizable-generation.md` |91| Generate valid molecules for exploration | `molecular-generation.md` |92| Plan a route to a known target molecule | `retrosynthesis-planning.md` |93| Predict one reaction step | `singlestep-retrosynthesis.md` |94| Check whether a proposed reaction route is plausible | `forward-and-reaction-modeling.md`, then `synthesizability-scoring.md` |95| Prepare or predict a receptor structure | `protein-structure-prediction.md` |96| Dock a ligand into a known structure | `docking-and-cofolding.md` |97| Co-fold a protein-ligand complex from sequence and ligand | `docking-and-cofolding.md` |98| Estimate binding affinity | `binding-affinity-and-fep.md` |99| Build a QSAR or property model | `property-and-qsar-prediction.md` |100| Screen ADMET risk | `admet-prediction.md` |101| Screen off-target or selectivity risk | `target-and-selectivity-prediction.md` |102| Generate molecules into a pocket | `structure-based-generation.md` |103| Orchestrate a full agentic loop | `agentic-drug-design.md`, then the category references it calls |104| Check a tool's terms for product-facing work | `licensing-and-data.md`, then the tool card |105106## First Picks107108Use these as starting points, then read the relevant reference file for details:109110| Need | First pick |111|---|---|112| Synthesizable-space projection | PrexSyn |113| Training-free analog generation | Review SynTwins after confirming its code terms; the repository has no `LICENSE` file |114| 3D molecule and route co-generation | Review SynCoGen; its weights and data are labeled MIT, but its code has no stated license |115| Make-on-demand design over Enamine-style libraries | SyntheMol; APEX has no stated repository or artifact license |116| General de novo molecule generation | GenMol after checking its separate model terms |117| Multi-step route planning | AiZynthFinder for a local baseline; RENKIN for route validation; ASKCOS when broader planning and conditions are needed |118| One-step retrosynthesis | ReactionT5v2 |119| LLM-assisted route planning | DeepRetro, RetroAgent, or Synthelite, followed by round-trip checks |120| Reaction templates and data cleanup | RDChiral or rdchiral_plus with rxnutils |121| ML affinity with MIT-licensed code and weights | Boltz-2 |122| Protein-ligand co-folding | OpenBind-0, Boltz-1, Chai-1, or Umol after checking the terms for the selected release |123| Learned docking into a known pocket | DiffDock-L or Uni-Mol Docking v2 |124| Classical CPU docking | AutoDock Vina |125| Physics-based relative free energy | OpenFE |126| QSAR from ChEMBL-style data | Chemprop or DeepChem |127| Local ADMET triage | ADMET-AI |128| Broad off-target scan | ChEMBL multitask model plus ESP-Sim where shape overlap matters |129| Pocket-conditioned generation | REINVENT 4, DiffSBDD, PILOT, Pocket2Mol, or TargetDiff, followed by makeability checks |130131## Operating Notes132133- Read source licenses directly. README badges and paper text can disagree with134 the repository license, model-card license, or dataset terms.135- Check code, weights, data, and base-model terms separately. For an LLM136 fine-tune, record both the project terms and the original base-model terms.137- Treat docking and co-folding confidence scores as pose-confidence signals.138 Binding-affinity estimates require an affinity model or a free-energy method.139- For molecular glues, degraders, covalent binders, and macrocycles, choose tools140 that model the complete mechanism. A single-pocket docking workflow omits141 important components of these systems.142- When an experimental ternary structure exists, perturb and score that143 structure before asking a co-folding model to predict it again.144- Pair pocket-conditioned generators with a makeability step. Most structure-145 based generators do not guarantee a synthesis route.146- Re-check upstream repositories for pre-1.0 models and entries with recent147 verification dates.148149## Pipeline Pattern150151A full design loop crosses both layers:1521531. Get or predict the receptor structure.1542. Generate, dock, co-fold, or score candidate molecules for the target.1553. Filter for affinity, QSAR, ADMET, and selectivity.1564. Project survivors into synthesizable space.1575. Plan or validate routes.1586. Re-check licenses and data terms before deployment.159160Load the detailed reference file for install commands, model weights, benchmark161context, GPU needs, and documented caveats.