Nobleblocks

Search 340 million deduplicated academic papers from Claude Desktop, Claude Web, ChatGPT, Cursor, VS Code Copilot, or any MCP-compatible tool. Covers 15+ academic databases — all cross-linked through a biomedical knowledge graph with 1.3M+ entities and 109M+ paper connections.

This is a thin authenticated client — all indexing, ranking, vector search, and knowledge graph traversal runs on the NobleBlocks backend. You get fast results without managing any infrastructure.

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What's in the index

Source	Papers	Updates
OpenAlex	~250M works	Daily
Semantic Scholar	~220M papers	Weekly
PubMed / MEDLINE	~41M articles	Daily
Europe PMC	~43M articles	Daily
Crossref	Incremental	Daily
arXiv	~2.5M preprints	Daily
bioRxiv / medRxiv	~1K/day	Daily
ClinicalTrials.gov	~582K trials	Daily
Unpaywall	OA link resolution	Daily
DBLP	Computer science	Via OpenAlex
CORE	~37M open access outputs	Coming soon
BASE (Bielefeld)	Discovery metadata	Via OpenAlex
DOAJ	Open access journals	Via Crossref
Papers with Code	ML/AI benchmarks	Weekly
Retraction Watch	Retraction status	Weekly
USPTO / EPO patents	~9.3M patent-paper links	Daily
…and others

All sources are cross-deduplicated on DOI, PMID, and arXiv ID. Total unique records after dedup: 340M+ (June 2026).

Knowledge graph

The search backend also maintains a biomedical knowledge graph (1.3M+ entities, 109M+ paper links) with genes, diseases, drugs, proteins, institutions, researchers, topics, genetic variants, and drug-target-disease relationships sourced from PubTator Central, DisGeNET, ChEMBL, UniProt, ROR, ORCID, Open Targets, and others.

Tools

Tool	What it does
search_papers	Full-text + semantic hybrid search with year/citation/source filters
get_paper	Fetch metadata by DOI, PMID, arXiv ID, or OpenAlex ID
find_similar	Find papers related by meaning, not just keyword matching
get_citation_graph	Citation network — references and citing papers
search_by_entity	Find papers linked to a gene, drug, disease, or institution via the KG
create_literature_review	AI-generated structured lit review with citations (Pro)

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Get an API key

All usage requires a free NobleBlocks account. Sign up takes 30 seconds:

1. Go to nobleblocks.com/signup
2. Create an account (email or Google)
3. Navigate to Settings > API Keys and generate a key

Free plan: 100 searches/day, 5 similar/day, citation graph access. Pro plan: 5,000 searches/day, literature review generation, priority support.

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Quick start (Remote — no install needed)

The easiest way to get started is the remote connector — no API keys, no Python install:

1. Open claude.ai → Settings → Connectors (or Integrations)
2. Click "Add" and paste: https://mcp.nobleblocks.com/mcp
3. Sign in with your NobleBlocks account
4. Ask Claude: "Search for papers on CRISPR gene therapy"

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Install (Local)

uvx nobleblocks-mcp

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Configure Claude Desktop

Add to your Claude Desktop config (~/Library/Application Support/Claude/claude_desktop_config.json on macOS):

{
  "mcpServers": {
    "nobleblocks": {
      "command": "nobleblocks-mcp",
      "env": {
        "NOBLEBLOCKS_API_KEY": "nb_pk_your_key_here"
      }
    }
  }
}

Restart Claude Desktop. The NobleBlocks tools will appear in the tools list.

Configure VS Code Copilot

Add to .vscode/mcp.json in your project:

{
  "servers": {
    "nobleblocks": {
      "command": "nobleblocks-mcp",
      "env": {
        "NOBLEBLOCKS_API_KEY": "nb_pk_your_key_here"
      }
    }
  }
}

Configure Cursor / Cline / Continue

Point your editor's MCP settings at the nobleblocks-mcp command with stdio transport. Set NOBLEBLOCKS_API_KEY in the environment.

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CLI usage

You can also search directly from the terminal:

# Search papers
nobleblocks search "CRISPR base editing" --limit 5 --min-year 2022

# Get a specific paper
nobleblocks get 10.1038/s41586-020-2649-2

# Find similar papers
nobleblocks similar "Attention Is All You Need"

# Citation graph
nobleblocks citations 10.1038/s41586-020-2649-2 --direction both

All CLI commands require NOBLEBLOCKS_API_KEY set in your environment (or pass --key).

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Environment variables

Variable	Default	Description
NOBLEBLOCKS_API_KEY	(required)	Your API key from nobleblocks.com
NOBLEBLOCKS_API_BASE	https://www.nobleblocks.com	API endpoint
LOG_LEVEL	INFO	Logging verbosity

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Examples

Once configured, ask naturally in Claude/Cursor:

"Find the most-cited papers on CRISPR base editing from 2022-2024"

"Show me papers similar to 'Attention Is All You Need' by Vaswani"

"What papers cite DOI 10.1038/s41586-020-2649-2?"

"Find papers linking BRCA1 to drug resistance"

"Generate a literature review on CAR-T cell therapy in solid tumors"

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Development

git clone https://github.com/nobleblocks/nobleblocks-mcp.git
cd nobleblocks-mcp
pip install -e .

# Test with MCP Inspector
npx @modelcontextprotocol/inspector nobleblocks-mcp

License

MIT — see LICENSE.

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Built by NobleBlocks — the academic research platform for the AI era.