maxAtoms
/maxBonds bound the atom/bond preview and includeRawSdf opts into a large raw SDF past the safe line cap; atomCount/bondCount always report the totals and any capping is disclosed
How to use it
maxAtoms is exposed by the Pubchem MCP Server MCP server. Add the server to your MCP client (Claude Desktop, Cursor, Windsurf and others), and the maxAtoms tool becomes available to the model automatically. See the full listing for setup details and every tool this server provides.
Install Pubchem MCP Server
docker run -p 3010:3010 pubchem-mcp-serverOther tools in Pubchem MCP Server (10)
Get a compound's bioactivity profile: assay results, targets, and activity values; filter by outcome or molecular target.
Fetch a 3D conformer (atomic coordinates and bonds) for a compound by CID, as parsed JSON or raw SDF.
Get physicochemical properties, descriptions, synonyms, drug-likeness, and classification for compounds by CID.
Fetch a 2D structure diagram (PNG) for a compound by CID.
Get drug-drug, drug-food, and chemical-target interactions for a compound by CID.
Get GHS hazard classification and safety data for one or more compounds by CID (batch).
Get external database cross-references (PubMed, patents, genes, proteins, etc.).
Get summaries for PubChem entities: assays, genes, proteins, taxonomy.
Find bioassays by biological target (gene symbol, protein, Gene ID, UniProt accession).
Search for compounds by name, SMILES, InChIKey, formula, substructure, superstructure, or 2D similarity.