Scholar Sidekick MCP Server

MCP server for Scholar Sidekick — catch AI-fabricated citations, one at a time or across a whole bibliography, from any AI assistant. It also checks retraction and open-access status, and resolves any scholarly identifier (DOI, PMID, PMCID, ISBN, arXiv, ISSN, NASA ADS bibcode, WHO IRIS URL) into 10,000+ CSL styles or nine export formats.

Highlights

• Citation-fabrication detection — verifyCitation cross-checks a claimed citation against the resolved record at its identifier, detecting the dominant AI-driven fabrication pattern documented by Topaz et al. (Lancet 2026) — real DOI + invented title — that simple identifier resolution cannot catch. Long-form explainer at scholar-sidekick.com/citation-integrity.
• Whole-bibliography audit — auditBibliography runs that same check plus a retraction lookup across an entire reference list in one call, taking raw BibTeX, RIS, or CSL JSON and returning a per-entry verdict table with a corpus summary.
• Retraction & open-access checks — checkRetraction surfaces retractions, corrections, and expressions of concern (Crossref / Retraction Watch); checkOpenAccess returns OA status and the best legal landing or PDF URL (Unpaywall). Both accept any identifier type and resolve it to a DOI under the hood.
• Eight identifier types out of the box — DOIs, PMIDs, PMCIDs, ISBNs, arXiv IDs, ISSNs, NASA ADS bibcodes, and WHO IRIS URLs (rare in citation tooling).
• Batch-friendly resolve / format / export — each accepts a single identifier or a comma- or newline-separated list; the server normalises the list and resolves them in one round trip.
• 10,000+ citation styles — five hand-tuned builtins (Vancouver, AMA, APA, IEEE, CSE) plus any CSL style ID, with alias and dependent-style resolution.
• Nine export formats — BibTeX, RIS, CSL JSON, EndNote (XML/Refer), RefWorks, MEDLINE, Zotero RDF, CSV, plain text.
• Composable workflow — chain resolveIdentifier → formatCitation → exportCitation in one prompt for an end-to-end "raw IDs → exportable bibliography" pipeline.
• Provenance metadata on every response — formatted output is followed by a metadata block (requestId, formatter, styleUsed, warnings) so the assistant can show users which engine produced each citation.
• No key required — works anonymously against the public Scholar Sidekick API (rate-limited free tier); add a free first-party ssk_ key for higher limits, or a RapidAPI key for paid/managed tiers.
• Hosted HTTP endpoint (no install) — prefer not to run a local stdio server? Connect any HTTP-capable MCP client straight to https://scholar-sidekick.com/api/mcp (Streamable HTTP, same 7 tools). See Hosted HTTP endpoint.
• REST API twin — the same endpoints are available as the Scholar Sidekick REST API for non-MCP integrations.

Tools

| Tool | Description | | --- | --- | | verifyCitation | Verify a claimed citation against the resolved record at its identifier. Detects the Topaz et al. (Lancet 2026) fabrication pattern — real DOI + invented title — that resolveIdentifier alone cannot catch. Returns one of four verdicts (matched / mismatch / ambiguous / not_found) plus per-field similarity scores and the resolved record so the user can see where the cited title and the actual paper diverged. Optional Stage 3 LLM screen rescues informal-abbreviation false positives (paid plans / first-party authentication only). One citation per call. | | auditBibliography | Run the verifyCitation check plus a retraction lookup across a whole bibliography in one call. Accepts raw BibTeX, RIS, or CSL-JSON text, or a pre-parsed claims[] array; returns a per-entry verdict table and a corpus summary. Capped at 25 entries per call. | | resolveIdentifier | Resolve DOIs, PMIDs, PMCIDs, ISBNs, arXiv IDs, ISSNs, ADS bibcodes, and WHO IRIS URLs to structured bibliographic metadata (CSL JSON). Accepts a single identifier or a comma/newline-separated batch. | | formatCitation | Format one or many identifiers into Vancouver, AMA, APA, IEEE, CSE, or any of 10,000+ CSL styles. Output as text, HTML, or JSON. Returns formatted citations plus a provenance metadata block. | | exportCitation | Export one or many identifiers to BibTeX, RIS, CSL JSON, EndNote (XML/Refer), RefWorks, MEDLINE, Zotero RDF, CSV, or plain text — ready to write to disk or hand to a reference manager. | | checkRetraction | Check whether a single work has been retracted, corrected, or had an expression of concern raised. Sourced from Crossref updated-by (Retraction Watch). Resolves DOI/PMID/PMCID/arXiv/ADS inputs to a DOI before lookup. One identifier per call. | | checkOpenAccess | Check whether a single work is openly accessible and where to find the best legal version. Sourced from Unpaywall. Returns OA status (gold/green/hybrid/bronze/closed), best landing/PDF URL, license, and version. Resolves DOI/PMID/PMCID/arXiv/ISBN/ADS inputs to a DOI before lookup. One identifier per call. |

All seven tools are read-only (readOnlyHint: true, destructiveHint: false). The exact tools/list payload — descriptions, JSON Schemas, and annotations — is committed as tools.json and ships in the npm tarball, so you can review the full tool surface without running anything.

Setup

No key required. The server works anonymously against the public Scholar Sidekick API (https://scholar-sidekick.com) at a rate-limited free tier — just install and go. To raise your limits, create a free first-party ssk_ key at scholar-sidekick.com/account and set SCHOLAR_API_KEY. For paid/managed tiers, subscribe on RapidAPI and set RAPIDAPI_KEY (which routes calls through the RapidAPI gateway).

Prefer zero install? There's also a hosted HTTP endpoint at https://scholar-sidekick.com/api/mcp (Streamable HTTP) — connect any HTTP-capable MCP client directly, no npx needed. See Hosted HTTP endpoint below. The stdio package documented here is the local-install alternative (and the path for RapidAPI-keyed users).

Claude Desktop

Add to ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows). No key, no env block:

{
  "mcpServers": {
    "scholar-sidekick": {
      "command": "npx",
      "args": ["-y", "scholar-sidekick-mcp@latest"]
    }
  }
}

Only if you want higher rate limits, add an env block with a free ssk_ key from scholar-sidekick.com/account:

"env": { "SCHOLAR_API_KEY": "ssk_…[redacted]" }

Claude Code

# Anonymous (no key):
claude mcp add scholar-sidekick -- npx -y scholar-sidekick-mcp@latest

# With a free first-party key for higher limits:
claude mcp add scholar-sidekick \
  -e SCHOLAR_API_KEY=ssk_…[redacted] \
  -- npx -y scholar-sidekick-mcp@latest

Claude Code plugin (server + skill in one step)

This repo is also a Claude Code plugin marketplace. Installing the plugin wires up the MCP server and the companion agent skill together — no separate claude mcp add, no env block:

/plugin marketplace add mlava/scholar-sidekick-mcp
/plugin install scholar-sidekick@scholar-sidekick

The plugin runs the server anonymously (no key). For higher rate limits, add a free ssk_ key from scholar-sidekick.com/account via claude mcp add as shown above, or use the hosted endpoint below.

Cursor / VS Code / Windsurf

Add to .cursor/mcp.json or .vscode/mcp.json. No key needed:

{
  "mcpServers": {
    "scholar-sidekick": {
      "command": "npx",
      "args": ["-y", "scholar-sidekick-mcp@latest"]
    }
  }
}

For higher rate limits, add "env": { "SCHOLAR_API_KEY": "ssk_…[redacted]" }.

Run in a container (sandboxed)

The server speaks MCP over stdio and needs outbound HTTPS to the Scholar Sidekick API and nothing else — no filesystem access, no shell. If your policy is that MCP servers don't get host access, build the image in this repo and run it isolated:

docker build -t scholar-sidekick-mcp .

{
  "mcpServers": {
    "scholar-sidekick": {
      "command": "docker",
      "args": [
        "run", "-i", "--rm",
        "--read-only", "--cap-drop", "ALL", "--security-opt", "no-new-privileges",
        "scholar-sidekick-mcp"
      ]
    }
  }
}

-i is required — that's the stdio pipe. Add "-e", "SCHOLAR_API_KEY", to the args only if you are passing a key for higher limits. No image is published to a registry; build it locally so you're running a bundle you built from source you can read.

Agent skill (optional)

Install a companion Agent Skill that teaches Claude Code, Cline, and other agents when and how to use these tools — it complements the server config above:

npx skills add mlava/scholar-sidekick-mcp

Hosted HTTP endpoint (no install)

Don't want to run a local stdio server? Scholar Sidekick is also a hosted Streamable HTTP MCP at https://scholar-sidekick.com/api/mcp — the same seven tools, no npx, no local process. It works anonymously (rate-limited free tier); add an Authorization: Bearer ssk_… header (a free key from scholar-sidekick.com/account) for higher limits.

Point any HTTP-capable MCP client at it:

{
  "mcpServers": {
    "scholar-sidekick": {
      "type": "http",
      "url": "https://scholar-sidekick.com/api/mcp"
    }
  }
}

In Claude Desktop, use Settings → Connectors → Add custom connector (or "Add HTTP server") and paste the URL. Add the bearer token in the client's header/auth field if you have one.

Discovery: /.well-known/mcp.json (SEP-1649 server card) lists this endpoint plus the no-auth ChatGPT Apps endpoint at /api/apps/mcp. The stdio package above remains the local-install alternative and the path for RapidAPI-keyed users.

Environment Variables

| Variable | Required | Description | | --- | --- | --- | | SCHOLAR_API_KEY | No | Free first-party ssk_ key from scholar-sidekick.com/account; raises rate limits and enables the verifier's LLM screen. Sent as Authorization: Bearer. | | RAPIDAPI_KEY | No | RapidAPI subscription key for paid/managed tiers; when set, calls route through the RapidAPI gateway. | | RAPIDAPI_HOST | No | RapidAPI host (defaults to scholar-sidekick.p.rapidapi.com) | | SCHOLAR_SIDEKICK_URL | No | Override the API base URL (defaults to https://scholar-sidekick.com, or the RapidAPI gateway when RAPIDAPI_KEY is set). | | SCHOLAR_SIDEKICK_TIMEOUT_MS | No | Request timeout in milliseconds (default: 30000) |

No key at all → anonymous, rate-limited free tier. With both SCHOLAR_API_KEY and RAPIDAPI_KEY set, RapidAPI takes precedence.

Supported Citation Styles

Scholar Sidekick supports 10,000+ CSL styles, including all major formats used in academic publishing:

| Style | Keyword | | --- | --- | | Vancouver | vancouver | | APA (7th ed.) | apa | | AMA | ama | | IEEE | ieee | | CSE | cse | | Chicago (author-date) | chicago-author-date | | Harvard | harvard-cite-them-right | | MLA | modern-language-association | | Turabian | turabian-fullnote-bibliography | | Nature | nature | | BMJ | bmj | | Lancet | the-lancet |

Any [CSL style