"Web search services that don't require an API key" matching MCP servers:

Enables AI agents to query Human Phenotype Ontology clinical phenotype terms, navigate term hierarchies, and retrieve gene-disease and disease-phenotype annotations through keyless MCP tools.

Enables searching for academic papers and preprints across multiple platforms including Semantic Scholar, arXiv, PubMed, and CrossRef. It provides access to research records, DOI lookups, and journal metadata through a unified interface deployed on Cloudflare Workers.

Server to search PubMed (PubMed is a free, online database that allows users to search for biomedical and life sciences literature). I have created on a day MCP came out but was on vacation, I saw someone post similar server in your DB, but figured to post mine.

Enables search and retrieval of academic papers from PubMed database with advanced features like MeSH term lookup, publication statistics, and PICO-based evidence search.

Enables language models to search biomedical literature, fetch sequences, and follow links across Entrez databases through eleven read-only tools wrapping the nine NCBI Entrez E-utilities. It handles URL building, pacing, redirects, response caps, and API-key redaction so queries can be answered without a browser or scraping.

MCP server that exposes the UniProt REST API to LLM clients, enabling search and retrieval of protein data via tools like search_uniprotkb, get_entry, and map_ids.

An MCP server that gives Claude access to NCBI Datasets v2 — search genome assembly metadata, retrieve taxonomy records, and download data packages without leaving your conversation.

An MCP server that connects AI agents to the PEPTOMA open DeSci peptide research platform, enabling peptide sequence analysis, feed search, and peer-review annotations.

An MCP server that exposes the KEGG REST API — pathways, genes, compounds, reactions, enzymes, diseases, drugs, modules, orthology, glycans, and BRITE hierarchies, with cross-database linking. Provides 34 tools and 8 resource templates.

Enables querying NCI Thesaurus and other cancer-research vocabularies served by NCI Enterprise Vocabulary Services, providing codes, synonyms, definitions, and hierarchical relationships via MCP tools.

Enables AI agents to browse the Gene Ontology through the EBI QuickGO API, including keyword search for GO terms, retrieval of a term's name, aspect, definition and synonyms by id, and listing the GO annotations tied to a UniProt accession. Runs keyless over HTTP or as a local stdio server, with an optional gateway route that lets plain-English questions be answered without choosing tools manually.

An MCP server that enables language models to fetch protein information from the UniProt database, including protein details, sequences, functions, and structures.

Enables AI agents to search roughly 150 million digitized natural-history museum specimen records (plants, animals, fossils) from US collections, filtered by taxonomy and locality, and to retrieve the full normalized record for any single specimen by its uuid. It also returns taxonomic or geographic specimen counts grouped by a chosen field, optionally narrowed by the same filters, with no API key required.

Enables AI assistants to query VCF files through MCP tools that summarize variants, identify pathogenic and carrier variants, interpret pharmacogenomic results, and determine APOE status, with web app and Claude Desktop support.

Enables discovery and querying of public OpenBind structure-affinity datasets, experimental binding events, benchmark results, and live Fragalysis targets and observations through read-only REST endpoints without requiring an API key.

An MCP server that grounds protein research in the UniProt SPARQL endpoint, providing tools for querying proteins, sequences, variants, diseases, and more via intent-named tools and raw SPARQL.

MCP server that provides tools to query harmonized gene-disease validity data from the Gene Curation Coalition, supporting consensus and conflict detection for gene-disease assertions.

Enables coding agents to interact with the Reactome pathway database, including search, lookup, hierarchy traversal, SBML/SBGN export, and gene-set enrichment analysis.

Guides researchers, including those new to BPP, from raw sequence data to a validated control file that has passed a short test run. Wraps BPP command-line tools without running long analyses itself.

Provides read-only access to the ProPaths verified protein interactome, letting AI agents search proteins, retrieve mechanistic interaction details, and explore pathway ontology through MCP tools, resources, and prompts.