# agentsvc.io Citation Check

> agentsvc.io Citation Check is a paid API for AI agents from agentsvc.io, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-18).

Validates academic citations by checking whether a paper (by DOI, title, authors, or year) is real, correctly attributed, and findable — catching hallucinated or misattributed references.

## Facts

- Endpoint: POST https://agentsvc.io/api/v1/proxy/citation-check?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-18
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentsvc-io-citation-check-7edff839
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_PzhA-h1z20OWWunsb-wBM

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 agentsvc-io-citation-check-7edff839 -d '<json body>'
```

Example prompt: Can you check whether this citation is real and correctly attributed: 'Attention Is All You Need' by Vaswani et al., 2017, and also verify DOI 10.48550/arXiv.1706.03762?

## When to prefer this

Use this endpoint when you need to verify whether academic citations are genuine and correctly attributed — especially after LLM-generated content that may hallucinate references. It accepts DOIs, titles, authors, and years individually or in batch (up to 10). Prefer this over a general web search when you need structured validation with pass/fail results per citation rather than raw search results.

## Known failure modes

- DOI not found in known databases — returns validation failure for that entry
- Title is too ambiguous to resolve to a unique paper — returns low-confidence or no match
- Input citations array exceeds 10 items — rejected by schema validation
- Malformed DOI string — may return error or unresolvable result
- Paper exists in a database not covered — false negative possible
- Network timeout reaching upstream scholarly databases — may return error

## How this service works

Verify references before you publish or rely on them: up to 10 citations per call, as reference strings in any style, DOIs, or {title, authors, year, doi}. For each: status verified, mismatch (the work exists but authors, year or DOI are wrong, e.g. a real DOI that points to a different paper), uncertain or not_found (likely invented), the matched record with authors, year, venue, DOI and open-access link, the corrected issues, an APA-formatted reference, and a retraction flag with the notice…

## Output

A JSON object with a success flag and a data payload reporting whether each citation was found, whether metadata (title, authors, year, venue) matches known records, and any discrepancies or resolution failures for each input reference.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "doi": {
   "type": "string",
   "description": "Single DOI (alternative to citations)"
  },
  "year": {
   "type": "integer"
  },
  "title": {
   "type": "string",
   "description": "Single title (alternative to citations), optionally with authors and year"
  },
  "authors": {
   "type": "array",
   "items": {
    "type": "string"
   }
  },
  "citations": {
   "anyOf": [
    {
     "type": "array",
     "items": {
      "anyOf": [
       {
        "type": "string",
        "maxLength": 1000
       },
       {
        "type": "object",
        "properties": {
         "doi": {
          "type": "string"
         },
         "year": {
          "type": "integer"
         },
         "title": {
          "type": "string"
         },
         "venue": {
          "type": "string"
         },
         "authors": {
          "type": "array",
          "items": {
           "type": "string"
          }
         }
        }
       }
      ]
     },
     "maxItems": 10,
     "minItems": 1
    },
    {
     "type": "string",
     "maxLength": 10000
    }
   ],
   "description": "1 to 10 references: strings, or {title, authors, year, doi}; or one string with one reference per line"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "data": {},
  "success": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentsvc-io-citation-check-7edff839/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentsvc.io](https://www.zero.xyz/host/agentsvc.io/llms.txt)