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Api Endpoint

2s

Unified scientific literature search across arXiv (preprints), PubMed (biomedical), and Semantic Scholar (cross-field, with citation counts). Returns a flat array of papers with stable schema: source, sourceId, doi, title, authors, abstract, year, publishedAt, citationCount, url, pdfUrl. Partial failures surface in the errors array rather than failing the whole call. Optional filters: since (YYYY-MM-DD), sources (subset), limit (max 20 per source).

Open interactive test console

Offering

Provider
2s.io
Method
GET
Offering type
Api Endpoint
Transport type
http
Category
Science And Education
Delivery
Not provided
Pricing model
Not provided
x402 version
2

Endpoint context

URL
https://2s.io/api/papers/search
MIME type
application/json
First seen
2026-10-16T01:52:52.778Z
Last seen
Tags
public-records, identifiers, AI-agents, us-gov-data, X402, upto-billing, ai-gateway, agent-infrastructure

Website

Payment pricing

x402 payment terms are the authoritative price for calling this endpoint.

Payment option 1
0.006 USDC
Atomic price: 6000 · Network: eip155:8453 · Asset: USDC · Scheme: exact
Payment option 2
0.006 USDC
Atomic price: 6000 · Network: solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp · Asset: USDC · Scheme: exact
Raw x402 terms
[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "6000",
    "payTo": "0x2b6D4988Db4723E6908Db86Ab2b8dFBc51FC32C5"
  },
  {
    "scheme": "exact",
    "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
    "amount": "6000",
    "payTo": "TW6ntaGzvj63ZgPjszd4FCGmVTGfzv1MAYZbjYcyWhn"
  }
]

Observed health

Status
Healthy
Latest latency
116 ms
Average latency
234 ms
HTTP status
402
Last checked
Reachability
100% over 13 checks

Latency is measured to the first response headers. A reachable result does not verify response accuracy or merchant identity.

Input schema

{
  "type": "object",
  "properties": {
    "type": {
      "const": "http"
    },
    "method": {
      "const": "GET"
    },
    "queryParams": {
      "type": "object",
      "properties": {
        "q": {
          "type": "string",
          "minLength": 1,
          "maxLength": 500
        },
        "limit": {
          "type": "integer",
          "minimum": 1,
          "maximum": 20,
          "default": 10
        },
        "since": {
          "type": "string"
        },
        "sources": {
          "type": "string"
        }
      },
      "required": [
        "q"
      ],
      "additionalProperties": false
    }
  },
  "required": [
    "type",
    "method",
    "queryParams"
  ]
}

Output schema

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "type": "object",
  "properties": {
    "input": {
      "type": "object",
      "properties": {
        "type": {
          "const": "http"
        },
        "method": {
          "const": "GET"
        },
        "queryParams": {
          "type": "object",
          "properties": {
            "q": {
              "type": "string",
              "minLength": 1,
              "maxLength": 500
            },
            "limit": {
              "type": "integer",
              "minimum": 1,
              "maximum": 20,
              "default": 10
            },
            "since": {
              "type": "string"
            },
            "sources": {
              "type": "string"
            }
          },
          "required": [
            "q"
          ],
          "additionalProperties": false
        }
      },
      "required": [
        "type",
        "method",
        "queryParams"
      ]
    }
  },
  "required": [
    "input"
  ]
}