base-academic-search

name	base-academic-search
description	Search 400M+ open access documents via the BASE search engine API
metadata	{"openclaw":{"emoji":"🔍","category":"literature","subcategory":"search","keywords":["BASE","academic search","open access","Bielefeld","OAI-PMH","repository aggregator"],"source":"https://www.base-search.net/"}}

BASE (Bielefeld Academic Search Engine) API

Overview

BASE is one of the world's largest search engines for academic open access web resources. Operated by Bielefeld University Library, it indexes 400M+ documents from 11,000+ content providers including institutional repositories, preprint servers, and digital libraries. Unlike Google Scholar, BASE provides structured metadata, license information, and full-text links. The API is free with registration.

API Endpoints

Base URL

https://api.base-search.net/cgi-bin/BaseHttpSearchInterface.fcgi

Search

# Basic keyword search (JSON response)
curl "https://api.base-search.net/cgi-bin/BaseHttpSearchInterface.fcgi?\
func=PerformSearch&query=climate+change+adaptation&format=json&hits=20"

# Search with field filters
curl "https://api.base-search.net/cgi-bin/BaseHttpSearchInterface.fcgi?\
func=PerformSearch&query=dctitle:transformer+AND+dcsubject:NLP&format=json"

# Filter by document type and year
curl "https://api.base-search.net/cgi-bin/BaseHttpSearchInterface.fcgi?\
func=PerformSearch&query=deep+learning&dctypenorm=121&dcyear:2024&format=json"

# Open access only
curl "https://api.base-search.net/cgi-bin/BaseHttpSearchInterface.fcgi?\
func=PerformSearch&query=CRISPR&dcrights:open&format=json"

Search Fields

Field	Description	Example
dctitle	Title	dctitle:attention+mechanism
dccreator	Author	dccreator:vaswani
dcsubject	Subject/keywords	dcsubject:machine+learning
dcdescription	Abstract	dcdescription:neural+network
dcyear	Publication year	dcyear:2024
dctype	Document type text	dctype:article
dctypenorm	Normalized type code	121 (journal article)
dcrights	Access rights	dcrights:open
dclang	Language	dclang:eng
dclink	Source URL	dclink:arxiv.org
dcoa	Open access status	dcoa:1 (OA), dcoa:2 (restricted)
dcprovider	Content provider	dcprovider:arxiv.org

Document Type Codes

Code	Type
121	Journal article
122	Book / monograph
14	Conference paper
15	Thesis / dissertation
17	Report
18	Preprint

Query Parameters

Parameter	Description	Default
func	Must be PerformSearch	Required
query	Search query with optional field prefixes	Required
format	Response format: json or xml	xml
hits	Results per page (max 125)	10
offset	Pagination offset	0
sortby	Sort: dcyear desc, score desc	relevance

Response Structure

{
  "response": {
    "numFound": 45200,
    "start": 0,
    "docs": [
      {
        "dctitle": "Attention Is All You Need",
        "dccreator": ["Ashish Vaswani", "Noam Shazeer"],
        "dcyear": "2017",
        "dcsubject": ["machine learning", "attention mechanism"],
        "dcdescription": "The dominant sequence transduction models...",
        "dcidentifier": "https://arxiv.org/abs/1706.03762",
        "dcsource": "arXiv.org",
        "dcprovider": "arxiv.org",
         
         
         
         
      
    
  

Python Usage

import requests

BASE_URL = "https://api.base-search.net/cgi-bin/BaseHttpSearchInterface.fcgi"


def search_base(query: str, hits: int = 20,
                doc_type: int = None, oa_only: bool = False) -> list:
    """Search BASE for academic open access documents."""
    q = query
    if doc_type:
        q += f" AND dctypenorm:{doc_type}"
    if oa_only:
        q += " AND dcoa:1"

    params = {
        "func": "PerformSearch",
        "query": q,
        "format": "json",
        "hits": hits,
        "sortby": "dcyear desc",
    }

    resp = requests.get(BASE_URL, params=params)
    resp.raise_for_status()
    data = resp.json()

    results = []
    for doc in data.get("response", {}).get("docs", []):
        results.append({
            "title": doc.get("dctitle"),
            "authors": doc.get("dccreator", []),
            "year": doc.get("dcyear"),
            "source": doc.get("dcsource"),
            "url": doc.get("dcidentifier"),
            "abstract": (doc.get("dcdescription") or "")[:300],
            : doc.get() == ,
            : doc.get(, []),
        })
     results


 () -> :
    
    query = 
     search_base(query, hits=)


 () -> :
    
    full_query = 
     search_base(full_query)



papers = search_base(, hits=, oa_only=)
 p  papers:
    oa =   p[]  
    ()


theses = search_dissertations()
 t  theses:
    ()

BASE vs Other Search Engines

Feature	BASE	Google Scholar	OpenAlex
Records	400M+	Unknown	250M+
Open access focus	Yes	No	Yes
Structured API	Yes	No official API	Yes
License metadata	Yes	No	Partial
Dissertation coverage	Excellent	Good	Limited
Repository-level filtering	Yes	No	No

References

• BASE Search Engine
• BASE API Documentation
• BASE Content Providers