Search Crossref
search_crossrefSearch academic papers from CrossRef database.
How it works ↓Pricing
Per call
$0.01
Model
flat
Pay only for what you use. No subscriptions.
Inputs
kwargs *
stringmax_results
integerquery *
stringInput Parameters
Cost per run
Execution cost$0.01
About Search Crossref
Search academic papers from CrossRef database.
CrossRef is a scholarly infrastructure organization that provides
persistent identifiers (DOIs) for scholarly content and metadata.
It's one of the largest citation databases covering millions of
academic papers, journals, books, and other scholarly content.
Args:
query: Search query string (e.g., 'machine learning', 'climate change').
max_results: Maximum number of papers to return (default: 10, max: 1000).
**kwargs: Additional search parameters:
- filter: CrossRef filter string (e.g., 'has-full-text:true,from-pub-date:2020')
- sort: Sort field ('relevance', 'published', 'updated', 'deposited', etc.)
- order: Sort order ('asc' or 'desc')
Returns:
List of paper metadata in dictionary format.
Examples:
# Basic search
search_crossref("deep learning", 20)
# Search with filters
search_crossref("climate change", 10, filter="from-pub-date:2020,has-full-text:true")
# Search sorted by publication date
search_crossref("neural networks", 15, sort="published", order="desc")
Frequently Asked Questions
Search academic papers from CrossRef database. CrossRef is a scholarly infrastructure organization that provides persistent identifiers (DOIs) for scholarly content and metadata. It's one of the largest citation databases covering millions of academic papers, journals, books, and other scholarly content. Args: query: Search query string (e.g., 'machine learning', 'climate change'). max_results: Maximum number of papers to return (default: 10, max: 1000). **kwargs: Additional search parameters: - filter: CrossRef filter string (e.g., 'has-full-text:true,from-pub-date:2020') - sort: Sort field ('relevance', 'published', 'updated', 'deposited', etc.) - order: Sort order ('asc' or 'desc') Returns: List of paper metadata in dictionary format. Examples: # Basic search search_crossref("deep learning", 20) # Search with filters search_crossref("climate change", 10, filter="from-pub-date:2020,has-full-text:true") # Search sorted by publication date search_crossref("neural networks", 15, sort="published", order="desc")
Search Crossref costs $0.01 per call on xpay. No subscription, no minimums. Pay only for the calls you make. New accounts get $5 in free credits.
Connect the Paper Search MCP endpoint to your client — Claude Code: claude mcp add --transport http paper-search "https://paper-search.mcp.xpay.sh/mcp?key=YOUR_XPAY_KEY"; Cursor/Windsurf/Cline/VS Code: same URL in mcp.json. The agent will see search_crossref as a callable tool with the input schema and run it directly. (Unified across all providers: https://mcp.xpay.sh/mcp?key=YOUR_XPAY_KEY, then xpay_run with toolPath paper-search/search_crossref.)
Yes — that's exactly what xpay is for. You don't need a Paper Search account or API key. Sign up at xpay.tools (Google or email), get $5 free credit, and run Search Crossref immediately. Billing flows through your xpay balance.
Search Crossref accepts 3 input parameters: kwargs, max_results, query. See the input schema and runnable form on this page for details and to test live.