# Academic Paper Search

> Academic Paper Search is a paid API for AI agents from papers.use.x402atlas.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-11-03).

Searches scientific and academic literature across arXiv, PubMed, OpenAlex, Crossref, and Semantic Scholar in a single deduplicated, retraction-aware call, returning ranked results with citation metrics and open-access PDF links.

## Facts

- Endpoint: GET https://papers.use.x402atlas.com/search?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-11-03
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/academic-paper-search-53862c1b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_9Oq0P6ZTzaTcRonWU2-0j

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability academic-paper-search-53862c1b
```

Example prompt: Search across arXiv, PubMed, and Semantic Scholar for up to 30 papers on transformer-based protein structure prediction published between 2020 and 2024, sorted by citations per year, and only include ones with a free PDF available.

## When to prefer this

Choose this endpoint when you need to search scientific literature across multiple databases simultaneously without managing separate API keys or deduplication logic. It is ideal for literature reviews, research discovery, and citation analysis workflows where cross-source coverage matters. Prefer it over single-source APIs (PubMed-only, arXiv-only) when breadth is important. Use the companion Academic Paper Lookup endpoint when you already have a specific DOI or arXiv ID and need the full abstract and TLDR.

## Known failure modes

- Empty results if the query is too narrow or uses jargon not indexed by the underlying sources
- Truncated or missing snippets for papers with restricted abstracts
- Missing PDF URLs when no open-access version exists (especially for paywalled journals)
- Year range filtering may exclude undated papers (year=0)
- Rate limiting or payment failure resulting in HTTP 402 or 429 errors
- Source-specific outages may reduce coverage without explicit error if other sources still return results

## How this service works

Scientific and academic paper search: research papers and scholarly literature from arXiv, PubMed, OpenAlex, Crossref and Semantic Scholar in one call, deduplicated and retraction-aware. Each hit: DOI, authors, venue, snippet, citation count and citations per year, type, open-access PDF link. Sort by relevance, recency, citations or impact. Keyless. For literature review and citing research.

## Output

Returns a JSON object containing the total count of matching papers and an array of paper records, each with a unique ID (DOI or source-specific ID), title, authors, publication year, venue, abstract snippet, DOI, citation count, citations per year, paper type (journal-article, preprint, review, book-chapter, or other), open-access status, PDF URL (if available), landing page URL, and a retraction flag. Results are deduplicated across sources and can be sorted by relevance, recency, citations, or impact (citations per year).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "query"
     ],
     "properties": {
      "sort": {
       "enum": [
        "relevance",
        "recency",
        "citations",
        "impact"
       ],
       "type": "string",
       "default": "relevance",
       "description": "impact = citations per year"
      },
      "limit": {
       "type": "integer",
       "default": 20,
       "maximum": 50,
       "minimum": 1
      },
      "query": {
       "type": "string",
       "maxLength": 500,
       "description": "Free-text search"
      },
      "source": {
       "enum": [
        "all",
        "arxiv",
        "pubmed",
        "openalex",
        "crossref",
        "semanticscholar"
       ],
       "type": "string",
       "default": "all"
      },
      "year_to": {
       "type": "integer",
       "maximum": 9999,
       "minimum": 1
      },
      "year_from": {
       "type": "integer",
       "maximum": 9999,
       "minimum": 1
      },
      "open_access": {
       "type": "boolean",
       "default": false,
       "description": "true keeps only items with a pdfUrl"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "query",
      "count",
      "items",
      "coverage"
     ],
     "properties": {
      "note": {
       "type": "string",
       "description": "Present only on a sample or empty response"
      },
      "count": {
       "type": "integer"
      },
      "items": {
       "type": "array",
       "items": {
        "type": "object",
        "required": [
         "id",
         "title",
         "authors",
         "year",
         "venue",
         "snippet",
         "doi",
         "citationCount",
         "citationsPerYear",
         "is_retracted",
         "type",
         "oa_status",
         "pdfUrl",
         "url",
         "detail_url"
        ],
        "properties": {
         "id": {
          "type": "string"
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/academic-paper-search-53862c1b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from papers.use.x402atlas.com](https://www.zero.xyz/host/papers.use.x402atlas.com/llms.txt)