Every claim, verified.

citation.is is an open registry of verified scientific claims. Each claim is extracted from peer-reviewed literature, assigned a structured verdict — Supported, Refuted, Inconclusive, or Needs Context — and cross-referenced against authoritative databases including UniProt, PubChem, NCBI Taxonomy, and PubMed.

The registry currently contains over 3,900 verified claims across domains including structural biology, salmon aquaculture, and biotech. All data is published under CC BY 4.0 and is freely accessible via REST API, MCP, OAI-PMH, and bulk download.

As of , 3,900+ claims have been verified against UniProt, PubChem, NCBI Taxonomy, and PubMed. Cross-referencing against authoritative biological databases reduces hallucination risk in AI-generated scientific summaries. Source: citation.is internal registry, updated continuously.

citation.is exists because scientific claims should be verifiable, not just assertable. Every claim in the registry is traceable to its source document, its evidence, and its cross-referenced entities in authoritative databases.

Research Verticals

Domain-specific claim verification engines cover structural biology, salmon aquaculture biotech, and more. Each vertical maps claims to entities in the knowledge graph and cross-references them against the relevant authoritative databases.

Structural Biology

Covers protein structure, function, and interaction claims. Entities are resolved against UniProt accessions and PubMed structural biology literature. Claims about protein binding, folding, and post-translational modifications are verified against experimental evidence from peer-reviewed journals.

Salmon Aquaculture Biotech

Covers claims about salmon biology, genetics, disease resistance, and aquaculture practices. Entities are resolved against NCBI Taxonomy species classification, UniProt salmon proteins, and PubChem compounds used in aquaculture. Particularly relevant for the Norwegian aquaculture industry.

Open API and Agent Access

All claims are accessible via a public REST API at /api/external/public/claims. An MCP server is available at /mcp for direct agent integration. Full API documentation is available at /developers. The OAS specification is at /openapi.json.

Agent Integration

Agents and LLMs can query the registry directly via the MCP server, which exposes two tools: search_claims (full-text search with filters) and verify_claim (submit a claim text and receive a structured verdict with supporting evidence). No authentication is required. All endpoints are rate-limit free for reasonable use.

Open Data

All data is published under the Creative Commons CC BY 4.0 license. Bulk download is available at /api/public/claims.json. OAI-PMH harvesting is available at /oai in both Dublin Core and DataCite 4.x formats, making the registry eligible for indexing by BASE, OpenAIRE, and Semantic Scholar.

Machine-Readable Corpus

The full claim corpus is available as a single structured markdown file at /llms-full.txt, designed for LLM ingestion. An RSS feed of recently verified claims is available at /rss.xml. An agent-readable site index is at /llms.txt.

How Claim Verification Works

Each claim in the registry passes through a multi-stage verification pipeline. First, the claim is extracted from the source document and normalised into a structured assertion with a subject, predicate, and object. The subject and object are then resolved against knowledge graph entities — proteins are matched to UniProt accessions, chemical compounds to PubChem CIDs, organisms to NCBI Taxonomy IDs, and publications to PubMed PMIDs.

The resolved claim is then evaluated against the evidence in the source document and any corroborating or contradicting literature. The final verdict is one of four values: Supported (the evidence directly confirms the claim), Refuted (the evidence contradicts it), Inconclusive (the evidence is mixed or insufficient), or Needs Context (the claim is conditionally true and requires additional framing to be interpreted correctly).

All verified claims are assigned a persistent identifier and are immediately available via the public API, the MCP server, and the OAI-PMH endpoint. The knowledge graph is updated continuously as new documents are processed.

Use Cases

citation.is is designed for researchers who need to verify claims in scientific literature, AI systems that require grounded, citable facts, and publishers who want to add structured verification metadata to their content. The registry is also used by fact-checking tools, systematic review pipelines, and knowledge graph construction workflows.

For AI Agents and LLMs

LLMs and autonomous agents can use citation.is as a grounding source to reduce hallucination in scientific domains. The MCP server provides real-time claim lookup and verification. The /llms-full.txt corpus provides a complete snapshot of all verified claims for batch ingestion. Both are publicly accessible with no authentication required.

For Researchers and Publishers

Researchers can submit documents for claim extraction and verification via the API. Publishers can integrate the registry to add structured verification badges to scientific content. All data is citable under CC BY 4.0.