Argus One

A DOI-based duplicate merger for Zotero

What is Argus One?

Argus One is a small Zotero plugin that solves exactly one problem: merging items that share the same DOI. Zotero’s built-in duplicate detector compares titles, creators, and years — useful, but the wrong tool when DOIs are the source of truth in a curated library.

Argus One groups items by normalized DOI, keeps the newest record’s field values, fills in blanks from older copies, unions tags, related items, and collection memberships, re-parents attachments and notes, and trashes the older copies — all in a single Zotero transaction.

Requirements

• Zotero 9 and later
• A user library with items that have DOIs (either in the dedicated DOI field or as DOI: … in the Extra field)

Installation

1. Download the latest .xpi from the Releases page.
2. In Zotero: Tools → Plugins.
3. Click the gear icon → Install Plugin From File…
4. Select the downloaded file.

Zotero plugin installation dialog

A full walkthrough

1. Find a library with duplicates

Suppose you have imported the same set of papers from two sources — a shared group folder and a personal RIS export — and you now have two copies of many DOIs scattered across collections.

Duplicate items spread across collections

2. Run the merger

Open Tools → Argus One: merge DOI duplicates…

Argus One scans your user library, ignoring attachments, notes, trashed items, and child items. It groups what remains by normalized DOI and shows a confirmation dialog:

Found 12 DOI duplicate groups covering 27 items.

Merging will:
  • Keep the newest record per DOI (by dateAdded)
  • Fill missing fields from older copies
  • Preserve every collection the duplicates appeared in
  • Move 15 older records to trash

Proceed?

3. What happens during the merge

For each group of items that share a DOI:

Step	Behaviour
Survivor selection	Newest dateAdded wins; ties broken by higher itemID.
Field conflicts	Survivor’s existing value wins. Only blank fields are filled from older copies.
Creators	Survivor’s creators are kept. If empty, borrowed from an older copy.
Tags	Unioned across all duplicates.
Related items	Unioned (excluding the merged-away items themselves).
Collections	Unioned — if the DOI was in collections A and B, the survivor ends up in both.
Attachments & notes	Re-parented from older copies to the survivor.
Older copies	Moved to trash. Not deleted permanently.

All of the above runs inside a single Zotero.DB.executeTransaction call. If anything throws, the entire merge is rolled back.

4. After the merge

A summary dialog shows how many groups were merged and how many records were trashed:

Argus One result dialog

Inspect the Zotero trash before emptying it. Once you are satisfied, Edit → Empty Trash.

DOI normalization

A DOI like https://doi.org/10.1000/XYZ.123, doi:10.1000/xyz.123, and 10.1000/XYZ.123 are all treated as the same key. Normalization:

• Lowercases the string
• Strips a leading https://doi.org/ or https://dx.doi.org/
• Strips a leading doi:
• Trims whitespace
• Requires the result to match ^10\..+/.+

If an item has no value in the dedicated DOI field, the Extra field is scanned for DOI: ….

What Argus One does not do

• It does not merge items without a DOI. Use Zotero’s Duplicate Items view for fuzzy title matching.
• It does not delete anything permanently. Losers move to trash.
• It does not modify group libraries in this version.

Citing Argus One

If you use Argus One in published work, please cite it. The canonical metadata lives in CITATION.cff.

BibTeX

@software{heller_argus_one_2026,
  author  = {Heller, Raban},
  title   = {Argus One: DOI-based duplicate merger for Zotero},
  year    = {2026},
  version = {0.1.0},
  license = {MIT},
  url     = {https://github.com/CTTIR/argus-one},
  note    = {Zotero 9+ plugin}
}

APA

Heller, R. (2026). Argus One: DOI-based duplicate merger for Zotero (Version 0.1.0) [Computer software]. https://github.com/CTTIR/argus-one

Links

• Source code: https://github.com/CTTIR/argus-one
• Issues: https://github.com/CTTIR/argus-one/issues
• Releases: https://github.com/CTTIR/argus-one/releases
• License: MIT