Scholar Sidekick - Cite from any identifier (Obsidian plugin)

Paste a DOI, PMID, ISBN, arXiv ID, ADS bibcode, or PMCID into a note and replace it with a formatted citation. No reference manager required.

Backed by the public Scholar Sidekick API — a transparent, composable interface to authoritative scholarly metadata sources (Crossref, NCBI, arXiv, Open Library, ADS, WHO IRIS).

Already using a Zotero / BibTeX library inside Obsidian? The Citations plugin is excellent for that workflow. Scholar Sidekick is for the case before you have a curated library - you want a citation now, from an identifier you have right now.

Commands

Command	What it does
Format selection as citation	Wraps the selected text (an identifier or text containing one) in a citation in your default style.
Replace identifier at caret with citation	Detects the identifier under or near the caret and replaces it (or appends, by setting). No selection required.
Insert citation…	Opens a modal: type/paste an identifier, pick from 5 quick styles or search 10,000+ CSL styles, insert at caret.
Export note citations to bibtex	Scans the active note for every identifier and saves a .bib file next to the note - ready to import into Zotero / Mendeley / EndNote.
Export note citations to ris	Same, but RIS format.
Check identifier at caret for retraction	Sends the identifier nearest the caret to the retraction checker (Crossref + Retraction Watch) and surfaces the result via a Notice.
Check identifier at caret for open access	Sends the identifier nearest the caret to the open-access checker (Unpaywall) and surfaces status + best legal copy via a Notice.
Check note citations for retractions	Scans the active note, dedupes identifiers, and opens a modal table with retraction status per item. Optional "Append summary at caret".
Check note citations for open access	Same, for open-access status. Modal lists each best legal copy link.
Verify selected citation	Opens a verifier modal pre-filled from the selection. Cross-checks the claimed title + identifier against Crossref, PubMed, OpenAlex.

Supported identifiers

• DOI (bare or doi.org URL)
• PMID (bare, labelled, or pubmed.ncbi.nlm.nih.gov URL)
• PMCID (bare or ncbi.nlm.nih.gov/pmc/articles/... URL)
• ISBN (10 or 13)
• arXiv (modern 2301.07041 or legacy cs.CL/0301001)
• ISSN
• ADS bibcode (within the modal - server-side detection)

The detection regexes are vendored from the upstream API source, with a build-time drift detector ensuring the vendored copy never falls out of sync with the canonical patterns.

Settings

• Default citation style - Vancouver, APA, AMA, IEEE, CSE built-in; the modal lets you persist any of 10,000+ styles.
• Output format - plain text or HTML. The five built-in styles emit text only; HTML applies to CSL styles selected via the search modal (those preserve italics, small caps, and other inline markup that survives in Obsidian's reading view). Selecting HTML with a built-in style falls back to text rather than failing.
• Replace mode - replace identifier in place, or append the citation after it.
• Include source provenance - sends ?provenance=1 so each citation records which upstream registry supplied the metadata, plus the fetch timestamp and transform version. Adds a small payload to every response.
• Include safety checks (retraction + open access) - sends ?checks=retraction,oa so each formatted citation arrives alongside its retraction status (Crossref + Retraction Watch) and open-access status (Unpaywall). Off by default; adds a few seconds of latency per request.

Privacy

• The plugin sends the identifier text you ask it to format directly to https://scholar-sidekick.com/api/format over HTTPS.
• The retraction / open-access / verify commands additionally send the identifier or claim to https://scholar-sidekick.com/api/retraction-check, https://scholar-sidekick.com/api/oa-check, or https://scholar-sidekick.com/api/verify over HTTPS.
• No API key is required; the API treats the plugin as the anonymous rate-limited tier (60 requests / minute / IP).
• Inputs are not retained or used for training. See the API privacy policy.

Provenance

Every API call carries a x-scholar-transform-version header so you can pin reproducibility. The plugin logs x-request-id and x-scholar-transform-version to the developer console for diagnostic support - open the Obsidian dev console (Cmd+Opt+I / Ctrl+Shift+I) to view them.

Build from source

See BUILD.md.