crossref-mcp

Polski

Crossref REST API MCP server. Wraps the public Crossref REST API (works, journals, funders, members, types, licenses) — no API key required.

Table of contents

• Tools
• Environment variables
• Wiring it up
• Local run

Tools

Tool	Parameters	Description
search_works	query, filter, select, sort, order, rows=20, offset=0, cursor	Search Crossref works (publications)
get_work	doi: str	Full metadata for a single work by DOI
get_work_agency	doi: str	Registration agency for a DOI
list_journals	query, rows=20, offset=0, cursor	List or search journals
get_journal	issn: str	Journal metadata by ISSN
get_journal_works	issn, query, filter, rows=20, offset=0, cursor	Works published in a journal
list_funders	query, filter, rows=20, offset=0	List or search funding bodies
get_funder	funder_id: str	Funder metadata by Funder Registry ID
list_members	query, filter, rows=20, offset=0	List or search Crossref members (publishers)
list_types_and_licenses	none	Available work types and licenses

Environment variables

Variable	Required	Description
CROSSREF_MCP_MAILTO	no	Email address for Crossref's "polite pool" — higher rate limits, faster responses

Wiring it up

Only requirement: uv (https://docs.astral.sh/uv/). Nothing else to install.

Claude Code

claude mcp add crossref-mcp -- uvx --from git+https://github.com/dam2452/crossref-mcp.git crossref-mcp

With the polite pool email set:

claude mcp add crossref-mcp -e CROSSREF_MCP_MAILTO=you@example.com -- uvx --from git+https://github.com/dam2452/crossref-mcp.git crossref-mcp

Claude Desktop / other MCP client

{
  "mcpServers": {
    "crossref-mcp": {
      "command": "uvx",
      "args": ["--from", "git+https://github.com/dam2452/crossref-mcp.git", "crossref-mcp"],
      "env": { "CROSSREF_MCP_MAILTO": "you@example.com" }
    }
  }
}

After pushing a new version: uv cache clean and restart the client.

Local run

uv run --directory . crossref-mcp

Tests (manual):

uv run --directory . --with pytest pytest test/