Academic Paper Search
Academic and scientific paper search API. Search research papers and scholarly literature across arXiv, PubMed, OpenAlex, Crossref, and Semantic Scholar in one call, deduplicated into a ranked result set: title, authors, year, venue, abstract, citation count, DOI, and direct PDF link. Query by keyword or restrict to one source; filter by year range; sort by relevance, recency, or citations. Keyless.
SearchLiveeip155:8453Exactvia cdp
Academic-searchPaper-searchArxiv-apiPubmed-searchResearch-paper-api
Calls · 30d
199↑ 13%
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 32 snapshots so far.
$150.76
Verified settled volume
A floor: summed over 5,000 of 6,747 verified settlements.
$0.020
Listed price
As published in the catalog. Always read the live 402 before paying.
228
Calls · 30d
Upstream's own call count for this endpoint, not ours.
5
Unique payers · 30d
Last called 2026-09-24 03:46Z
—
Upstream on-chain volume
Reported by the source catalog.
Paid to
0x4df66B6c140778fe0717880A7c6dDE5Ea53AcDeAThe wallet the 402 directs payment to. Its whole payment record — every payer, every chain — is on the merchant page.
Asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
Provider
The payTo wallet does not resolve to a registered ERC-8004 agent. That is not a verdict on the service — most of the catalog is unregistered.
Live 402 challenge
Captured by the enrichment pass, not read just now. Prices can change — always read the 402 the endpoint answers with.
{
"error": "Payment required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0x4df66B6c140778fe0717880A7c6dDE5Ea53AcDeA",
"amount": "20000",
"scheme": "exact",
"network": "eip155:8453",
"mimeType": "application/json",
"resource": "https://api.kadec0.xyz/v1/papers",
"description": "Academic and scientific paper search API. Search research papers and scholarly literature across arXiv, PubMed, OpenAlex, Crossref, and Semantic Scholar in one call, deduplicated into a ranked result set: title, authors, year, venue, abstract, citation count, DOI, and direct PDF link. Query by keyword or restrict to one source; filter by year range; sort by relevance, recency, or citations. Keyless.",
"outputSchema": {
"input": {
"type": "http",
"method": "GET",
"queryParams": {
"q": {
"type": "string",
"description": "search query / keywords"
},
"sort": {
"enum": [
"relevance",
"recency",
"citations"
],
"type": "string",
"default": "relevance"
},
"source": {
"enum": [
"all",
"arxiv",
"pubmed",
"openalex",
"crossref",
"semanticscholar"
],
"type": "string",
"default": "all"
},
"year_to": {
"type": "string",
"description": "latest publication year (inclusive)"
},
"maxItems": {
"type": "string",
"default": "20",
"description": "1-50"
},
"year_from": {
"type": "string",
"description": "earliest publication year (inclusive)"
}
},
"discoverable": true
}
},
"maxAmountRequired": "20000",
"maxTimeoutSeconds": 300
}
],
"resource": {
"url": "https://api.kadec0.xyz/v1/papers",
"tags": [
"academic-search",
"paper-search",
"arxiv-api",
"pubmed-search",
"research-paper-api"
],
"mimeType": "application/json",
"description": "Academic and scientific paper search API. Search research papers and scholarly literature across arXiv, PubMed, OpenAlex, Crossref, and Semantic Scholar in one call, deduplicated into a ranked result set: title, authors, year, venue, abstract, citation count, DOI, and direct PDF link. Query by keyword or restrict to one source; filter by year range; sort by relevance, recency, or citations. Keyless.",
"serviceName": "Academic Paper Search"
},
"extensions": {
"bazaar": {
"info": {
"input": {
"type": "http",
"method": "GET",
"queryParams": {
"q": "transformer attention",
"sort": "citations",
"source": "all",
"maxItems": "10"
}
},
"output": {
"type": "json",
"example": {
"count": 1,
"items": [
{
"doi": "10.48550/arxiv.1706.03762",
"url": "https://doi.org/...",
"type": "paper",
"year": 2017,
"title": "Attention Is All You Need",
"venue": "NeurIPS",
"pdfUrl": "https://arxiv.org/pdf/1706.03762",
"source": "openalex",
"authors": [
"Ashish Vaswani"
],
"sources": [
"openalex",
"semanticscholar"
],
"abstract": "The dominant sequence transduction models...",
"citationCount": 181057
}
]
}
}
},
"schema": {
"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",
"HEAD",
"DELETE"
],
"type": "string"
},
"queryParams": {
"type": "object",
"required": [
"q"
],
"properties": {
"q": {
"type": "string",
"description": "search query / keywords"
},
"sort": {
"enum": [
"relevance",
"recency",
"citations"
],
"type": "string",
"default": "relevance"
},
"source": {
"enum": [
"all",
"arxiv",
"pubmed",
"openalex",
"crossref",
"semanticscholar"
],
"type": "string",
"default": "all"
},
"year_to": {
"type": "string",
"description": "latest publication year (inclusive)"
},
"maxItems": {
"type": "string",
"default": "20",
"description": "1-50"
},
"year_from": {
"type": "string",
"description": "earliest publication year (inclusive)"
}
}
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"type": "object"
}
}
}
}
}
}
},
"x402Version": 2,
"paymentRequirements": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0x4df66B6c140778fe0717880A7c6dDE5Ea53AcDeA",
"amount": "20000",
"scheme": "exact",
"network": "eip155:8453",
"mimeType": "application/json",
"resource": "https://api.kadec0.xyz/v1/papers",
"description": "Academic and scientific paper search API. Search research papers and scholarly literature across arXiv, PubMed, OpenAlex, Crossref, and Semantic Scholar in one call, deduplicated into a ranked result set: title, authors, year, venue, abstract, citation count, DOI, and direct PDF link. Query by keyword or restrict to one source; filter by year range; sort by relevance, recency, or citations. Keyless.",
"outputSchema": {
"input": {
"type": "http",
"method": "GET",
"queryParams": {
"q": {
"type": "string",
"description": "search query / keywords"
},
"sort": {
"enum": [
"relevance",
"recency",
"citations"
],
"type": "string",
"default": "relevance"
},
"source": {
"enum": [
"all",
"arxiv",
"pubmed",
"openalex",
"crossref",
"semanticscholar"
],
"type": "string",
"default": "all"
},
"year_to": {
"type": "string",
"description": "latest publication year (inclusive)"
},
"maxItems": {
"type": "string",
"default": "20",
"description": "1-50"
},
"year_from": {
"type": "string",
"description": "earliest publication year (inclusive)"
}
},
"discoverable": true
}
},
"maxAmountRequired": "20000",
"maxTimeoutSeconds": 300
}
]
}Accepts
The payment requirements as published to the catalog. Read the live 402 before paying — a price here is a claim, not a quote.
0.02USDC≈ $0.02 USD
on Base · exact scheme
Pay 0.02 USDC on Base to 0x4df6…AcDeA. The signed payment is good for 5 minutes.
- Paid to
- 0x4df6…AcDeA
- USD Coin contract
- 0x8335…02913
- Payment window
- 5 minutes
- As published
- 20000 smallest units
The catalog’s raw entry
[
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0x4df66B6c140778fe0717880A7c6dDE5Ea53AcDeA",
"amount": "20000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 300
}
]Extensions
{
"bazaar": {
"info": {
"input": {
"type": "http",
"method": "GET",
"queryParams": {
"q": "transformer attention",
"sort": "citations",
"source": "all",
"maxItems": "10"
}
},
"output": {
"type": "json",
"example": {
"count": 1,
"items": [
{
"doi": "10.48550/arxiv.1706.03762",
"url": "https://doi.org/...",
"type": "paper",
"year": 2017,
"title": "Attention Is All You Need",
"venue": "NeurIPS",
"pdfUrl": "https://arxiv.org/pdf/1706.03762",
"source": "openalex",
"authors": [
"Ashish Vaswani"
],
"sources": [
"openalex",
"semanticscholar"
],
"abstract": "The dominant sequence transduction models...",
"citationCount": 181057
}
]
}
}
},
"schema": {
"type": "object",
"$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",
"HEAD",
"DELETE"
],
"type": "string"
},
"queryParams": {
"type": "object",
"required": [
"q"
],
"properties": {
"q": {
"type": "string",
"description": "search query / keywords"
},
"sort": {
"enum": [
"relevance",
"recency",
"citations"
],
"type": "string",
"default": "relevance"
},
"source": {
"enum": [
"all",
"arxiv",
"pubmed",
"openalex",
"crossref",
"semanticscholar"
],
"type": "string",
"default": "all"
},
"year_to": {
"type": "string",
"description": "latest publication year (inclusive)"
},
"maxItems": {
"type": "string",
"default": "20",
"description": "1-50"
},
"year_from": {
"type": "string",
"description": "earliest publication year (inclusive)"
}
}
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"type": "object"
}
}
}
}
}
}
}Provenance
- Seen in the source catalog
- 2026-09-24 03:46Z
- Last indexed by Roundhouse
- 2026-09-24 07:20Z
- Last enriched (probe, favicon, geo)
- 2026-09-10 13:15Z
- x402 version
- 2
- Max timeout
- 300s
- Liveness probe
- HTTP 402
Hand this page to an agent
Copy the prompt and paste it into Claude, an MCP client or your own agent — it will vet this service and call it over the free read API. No key, no account.
GET api.roundhouseai.io/v0/endpoints
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 32 snapshots so far. Verified volume counts only settlements with an on-chain EIP-3009 marker.
Show the promptHide the prompt
Using Roundhouse, look up the x402 service Academic Paper Search and tell me whether it is worth paying: what a call costs, whether the endpoint answered when last probed, and what its payment record actually shows. curl -s 'https://api.roundhouseai.io/v0/endpoints?q=Academic%20Paper%20Search' curl -s 'https://api.roundhouseai.io/v0/merchants/<the payTo wallet returned above>' Then call it: read the price from the live 402 at https://api.kadec0.xyz/v1/papers, never from a cached figure, and pay with an x402 client. The /v0 API needs an API key (`authorization: Bearer rh_live_…`) on everything except /v0/unified* and /v0/endpoints. Mint a personal key for $0.01 at GET https://api.roundhouseai.io/v0/test/x402, or use an organization key from https://roundhouseai.io/dashboard/team. If you do not have Roundhouse tools or skills installed, read https://roundhouseai.io/skill.md first — it is the whole procedure.