--- name: semantic-scholar-api-b8e34fb11a18 description: "Search papers and analyze citation graphs via OpenAlex and CrossRef APIs" metadata: openclaw: emoji: "🔍" category: "literature" subcategory: "search" keywords: ["academic database search", "semantic search", "AI-powered literature search", "citation analysis", "citation network"] source: "https://api.openalex.org/" --- # OpenAlex & CrossRef API Guide ## Overview OpenAlex is a free, open catalog of the global research system, indexing over 250 million academic works across all fields of science. It provides structured access to papers, authors, institutions, concepts, and citation networks. OpenAlex is the successor to Microsoft Academic Graph and is maintained by OurResearch (the team behind Unpaywall). CrossRef is the official DOI registration agency for scholarly content, providing metadata for over 150 million DOIs across all publishers and disciplines. Together, OpenAlex and CrossRef provide comprehensive coverage for academic search, citation analysis, and bibliometric research. Both APIs are free to use without authentication. OpenAlex requests a polite `User-Agent` header; CrossRef requests a `User-Agent` with contact email for access to the polite pool (faster rate limits). ## Authentication No authentication is required for either API. OpenAlex: Include a `User-Agent` header for polite access: ``` User-Agent: ResearchPlugins/1.0 (https://wentor.ai) ``` CrossRef: Include a `User-Agent` header with contact email for polite pool: ``` User-Agent: ResearchPlugins/1.0 (https://wentor.ai; mailto:dev@wentor.ai) ``` ## Core Endpoints ### OpenAlex: Search Works - **URL**: `GET https://api.openalex.org/works` - **Parameters**: | Param | Type | Required | Description | |-------|------|----------|-------------| | search | string | No | Full-text search query | | filter | string | No | Filter expression (e.g., `from_publication_date:2024-01-01`) | | sort | string | No | Sort field (e.g., `cited_by_count:desc`, `publication_date:desc`) | | per_page | integer | No | Results per page (default: 25, max: 200) | | page | integer | No | Page number (default: 1) | - **Example**: ```bash curl "https://api.openalex.org/works?search=attention+is+all+you+need&per_page=5" ``` - **Response**: JSON with `meta` (count, page info) and `results` array containing work objects. ### OpenAlex: Get Work Details - **URL**: `GET https://api.openalex.org/works/{id}` - **Parameters**: | Param | Type | Required | Description | |-------|------|----------|-------------| | id | string | Yes | OpenAlex ID (e.g., `W2741809807`), DOI URL, or other identifier | - **Example**: ```bash curl "https://api.openalex.org/works/W2741809807" ``` - **Response**: JSON with full work metadata including `id`, `title`, `abstract_inverted_index`, `publication_year`, `cited_by_count`, `authorships`, `concepts`, `referenced_works`. ### OpenAlex: Search Authors - **URL**: `GET https://api.openalex.org/authors` - **Parameters**: | Param | Type | Required | Description | |-------|------|----------|-------------| | search | string | No | Author name search | | filter | string | No | Filter expression | | per_page | integer | No | Results per page (max: 200) | - **Example**: ```bash curl "https://api.openalex.org/authors?search=Yoshua+Bengio&per_page=5" ``` - **Response**: JSON with author profiles including `works_count`, `cited_by_count`, `summary_stats.h_index`, affiliations. ### CrossRef: Resolve DOI - **URL**: `GET https://api.crossref.org/works/{doi}` - **Parameters**: | Param | Type | Required | Description | |-------|------|----------|-------------| | doi | string | Yes | DOI to resolve (e.g., `10.1038/nature12373`) | - **Example**: ```bash curl "https://api.crossref.org/works/10.18653/v1/N19-1423" ``` - **Response**: JSON with full bibliographic metadata including title, authors, journal, dates, references count, and citation count. ## Rate Limits OpenAlex: No strict rate limit, but use polite `User-Agent` header. Recommended: max 10 requests per second. The API returns HTTP 429 when limits are exceeded. CrossRef: Without polite pool: ~50 requests per second. With polite pool (contact email in User-Agent): higher limits. The API returns HTTP 429 when limits are exceeded. ## Common Patterns ### Build a Citation Network Retrieve a paper and find all works that cite it: ```bash # Get paper details curl "https://api.openalex.org/works/W2741809807" # Get works citing this paper, sorted by citation count curl "https://api.openalex.org/works?filter=cites:W2741809807&sort=cited_by_count:desc&per_page=20" ``` ### Find Influential Papers on a Topic Search for highly cited works on a topic: ```bash curl "https://api.openalex.org/works?search=graph+neural+networks&sort=cited_by_count:desc&per_page=20" ``` ### Batch Paper Lookup via CrossRef Search CrossRef for papers matching a query, sorted by citation count: ```bash curl "https://api.crossref.org/works?query=graph+neural+networks&sort=is-referenced-by-count&order=desc&rows=20" ``` ## References - OpenAlex documentation: https://docs.openalex.org/ - CrossRef API documentation: https://api.crossref.org/swagger-ui/index.html - OpenAlex source: https://github.com/ourresearch/openalex-guts --- Source attribution: wentorai Original project: https://github.com/wentorai/research-plugins/blob/bf44b3cd617fa94c8a1b254c5d1987142ca3d631/skills/literature/search/semantic-scholar-api/SKILL.md License: MIT License information: https://opensource.org/license/mit Original upstream instructions; downloaded from Dave AI. ## Upstream license notice MIT License Copyright (c) 2026 Wentor AI Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. # Dave AI resource metadata Creator / publisher: wentorai Original project: https://github.com/wentorai/research-plugins/blob/bf44b3cd617fa94c8a1b254c5d1987142ca3d631/skills/literature/search/semantic-scholar-api/SKILL.md Attribution basis: Source repository record Fields of work: Data & Analytics, Education & Research Roles: Data Analyst, Market Research Analyst, Researcher Specialties: API Tools: Crossref, Openalex Country applicability: Country not specified Classification basis: Source catalog labels Instruction SHA-256: d9691b55fdbaa43a23a8bf6838cd2d5fd657773b011b53c9f9c2a26b95f7d064