# SignalDesk AI – Europe PMC Article Lookup

> SignalDesk AI – Europe PMC Article Lookup is a paid API for AI agents from x402-agent.kariguetoazul.workers.dev, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-13).

Fetches bibliographic metadata for a scientific article from Europe PMC by record ID and source database

## Facts

- Endpoint: GET https://x402-agent.kariguetoazul.workers.dev/api/research/europepmc-article?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/signaldesk-ai-europe-pmc-article-lookup-f2e52fb9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_SSS1J0_uSi7TgEOmi18AV

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 signaldesk-ai-europe-pmc-article-lookup-f2e52fb9
```

Example prompt: Can you look up the Europe PMC article with MEDLINE ID 31452104 and tell me the title, authors, journal, DOI, and whether it's open access?

## When to prefer this

Use this endpoint when you need fast, structured bibliographic metadata for a specific article already identified by its Europe PMC record ID and source (MED for MEDLINE/PubMed, PMC for PubMed Central full-text, AGR for agricultural literature, CBA for Chinese biomedical). Prefer this over full-text search endpoints when you already have the record identifier and just need citation details, open access status, or DOI resolution. It is especially useful for enriching reference lists, verifying citations, or checking open access availability programmatically.

## Known failure modes

- Record not found (found: false) if the ID or source is incorrect
- Invalid source enum value returns a validation error
- ID format violation (non-alphanumeric characters) rejected by schema
- Network or upstream Europe PMC API unavailability may return an error
- Rate limit or quota exhaustion on the paid endpoint returns an HTTP 402 or quota error

## How this service works

Evidence-backed autonomous AI jobs and paid data tools. Queue/D1/cron run outside the chat; free quotas and bounded execution apply.

## Output

Returns a JSON object with found status, and if found: article title, DOI, Europe PMC URL, publication year, source, authors, journal name, and open access flag. Also includes source provenance metadata such as the upstream API URL, fetch timestamp, and expiry.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "id",
      "source"
     ],
     "properties": {
      "id": {
       "type": "string",
       "pattern": "^[A-Za-z0-9_-]+$",
       "maxLength": 40,
       "description": "Record ID."
      },
      "source": {
       "enum": [
        "MED",
        "PMC",
        "AGR",
        "CBA"
       ],
       "type": "string",
       "maxLength": 4096,
       "description": "Record source."
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "found": true,
  "record": {
   "id": "31452104",
   "doi": "10.1007/978-1-4939-9752-7_10",
   "url": "https://europepmc.org/article/MED/31452104",
   "year": "2019",
   "title": "Molegro Virtual Docker for Docking.",
   "source": "MED",
   "authors": "Bitencourt-Ferreira G, de Azevedo WF.",
   "journal": "Methods Mol Biol",
   "open_access": false
  },
  "source": {
   "provider": "Europe PMC public metadata",
   "expires_at": "2026-10-03T09:44:49.961Z",
   "fetched_at": "2026-10-02T09:44:49.961Z",
   "source_url": "https://www.ebi.ac.uk/europepmc/webservices/rest/search?query=EXT_ID%3A31452104%20AND%20SRC%3AMED&format=json&pageSize=1",
   "transformed": true
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/signaldesk-ai-europe-pmc-article-lookup-f2e52fb9/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-agent.kariguetoazul.workers.dev](https://www.zero.xyz/host/x402-agent.kariguetoazul.workers.dev/llms.txt)