FoldSift
A lightweight protein structure viewer and curation tool for VS Code.
FoldSift lets protein designers preview molecular structures inline, cycle through
a folder full of candidate designs, and triage the keepers into a CSV — without
ever leaving the editor. Rendering is powered by Mol*, the
same engine behind the RCSB PDB, so you get full representations, selections,
measurements, and screenshot/camera controls for free.
💡 Structure files still open as plain text by default, so you can read the
raw coordinates whenever you want. The 3D viewer is one right-click away.
Install
- Install FoldSift from the
VS Code Marketplace
— or open the Extensions panel (
Cmd/Ctrl+Shift+X), search FoldSift, and click Install.
- Right-click a structure file (or a folder of them) in the Explorer and pick a
FoldSift option:
- FoldSift: View Structure — open one structure in the 3D viewer.
- FoldSift: View Folder — cycle through every structure in a folder.
- FoldSift: Curate Structures — cycle and triage keepers into a CSV.
That's it — no setup or external tools required.
Features
- 3D structure viewer — the full Mol* viewport embedded in a VS Code tab.
- Folder cycling — step through every structure in a folder with the ◀ ▶
buttons, a slider, or the ←/→ arrow keys. Files load lazily, so a folder with
hundreds of designs stays light on memory.
- Curation to CSV — mark the structures you want to keep and export them, with
per-structure metadata and free-text comments, to a timestamped CSV.
- Wide format support — works with the formats below straight from raw text.
- Reads as text too — view the underlying coordinates anytime; the 3D editor is
opt-in, not forced.
| Extension(s) |
Format |
.pdb, .ent |
PDB |
.pdbqt |
AutoDock PDBQT |
.cif, .mmcif |
mmCIF |
.gro |
GROMACS |
.mol2 |
Tripos MOL2 |
.sdf, .sd |
SDF |
.mol |
MDL MOL |
.xyz |
XYZ |
.bcif |
BinaryCIF |
Any of the above may also be gzip-compressed (e.g. model.pdb.gz, 1abc.bcif.gz) —
FoldSift decompresses them transparently.
Usage
View a single structure
Right-click a structure file in the Explorer → FoldSift: View Structure.
(Or use Reopen Editor With… → FoldSift Structure Viewer from an open file.)
Cycle through a folder
Right-click a folder — or multi-select several files — → FoldSift: View Folder.
Use ◀ ▶, the slider, or the ←/→ arrow keys to move between structures.
Curate a set of structures
Right-click a folder → FoldSift: Curate Structures, then:
- Click Start selection — this creates
foldsift_selections_<timestamp>.csv
in the folder.
- While cycling, click Keep (or press S) to mark the current structure;
click/press again to unmark.
- Optionally type a note in the Comment box — it's saved per structure and
written next to it in the CSV.
- Click End selection to finish and open the CSV.
The CSV is rewritten atomically on every change, so unmarking a structure cleanly
removes its row and comment edits land immediately.
CSV columns
| Column |
Description |
index |
1-based position in the cycled set |
filename |
File name |
full_path |
Absolute path on disk |
format |
Parsed format (pdb, mmcif, …) |
num_chains |
Chain count |
num_residues |
Residue count |
num_atoms |
Atom count |
seq_length |
Sequence length |
sequence |
One-letter sequence, chains joined by / |
comment |
Your free-text note for this structure |
selected_at |
ISO-8601 timestamp when kept |
Sequence and counts are extracted for PDB-family and mmCIF inputs; coordinate-only
formats (e.g. .xyz, .gro, .mol2) render in the viewer but leave those columns
blank.
Settings
| Setting |
Default |
Description |
foldsift.recursiveFolderScan |
false |
Include structures in subfolders when scanning a folder. |
foldsift.backgroundColor |
#1e1e1e |
Viewport background color (hex). |
foldsift.keepHotkey |
s |
Single key used to toggle Keep during curation. |
Keyboard shortcuts
| Key |
Action |
← / → |
Previous / next structure |
S |
Toggle Keep on the current structure (during curation) |
The Keep key defaults to S and can be changed via foldsift.keepHotkey.
Shortcuts are ignored while the Comment box is focused, so you can type freely.
Requirements
Source code & contributing
FoldSift is open source (MIT). The code lives at
github.com/KodyKlupt/FoldSift — issues
and pull requests are welcome. To build it locally: npm install, npm run compile,
then press F5 in VS Code to launch an Extension Development Host.
Credits
Developed by Kody Klupt.
3D rendering by Mol* (Sehnal et al.). FoldSift bundles
Mol* and provides the VS Code integration and curation workflow.
License
Released under the MIT License © 2026 Kody Klupt.
