Extract citations & footnotes API

Pulls citations out of LLM prose — bracketed [1][2] references, [^fn] footnote markers and their definitions, and bare URLs — deduped and sorted, for grounding and attribution checks. Answers 'what sources did the model cite?', 'how do I extract footnotes and links from this answer?'.

Price$0.02per request

MethodPOST

Route/v1/llm/citations

StatusLive

MIME typeapplication/json

Rate limit120/minute

Cache0s public

llmcitationsfootnotesreferencesgroundingattributionextractagent

API URLhttps://x402.hexl.dev/v1/llm/citations

Integration docs

Example request

{
  "text": "See [1] and [2]. Also [^a].\n[^a]: A footnote. Visit https://x.com/page."
}

Example response

{
  "bracketed": [
    1,
    2
  ],
  "inlineMarkers": [
    "[^a]"
  ],
  "footnotes": [
    {
      "marker": "[^a]",
      "text": "A footnote. Visit https://x.com/page."
    }
  ],
  "urls": [
    "https://x.com/page."
  ],
  "count": 4
}

Input schema

{
  "type": "object",
  "required": [
    "text"
  ],
  "properties": {
    "text": {
      "type": "string",
      "examples": [
        "See [1] and [2]. Also [^a].\n[^a]: A footnote. Visit https://x.com/page."
      ]
    }
  }
}

Output schema

{
  "type": "object",
  "additionalProperties": true
}