"Search functionality without API key requirement" matching MCP servers:

An MCP server exposing the EU Birds Directive Art. 7(4) 'Key Concepts' data: the periods of reproduction and pre-nuptial migration for each huntable bird species in each Member State. It lets you check whether a given hunting-season date falls within a protected period.

MCP server for key driver and feature importance analysis based on rule mining

MCP server for searching Chinese academic literature from CNKI Space, returning metadata such as title, authors, year, and links, and retrieving abstracts and degree details. Enables agents to query CNKI without an account.

MCP server for PubMed search and literature summarization

Provides 27 tools for web search, content extraction, and data processing without requiring any API keys.

Gives Claude direct access to the Africa API for comprehensive data on all 54 African nations, including economic indicators, markets, trade, government, elections, and policies.

Enables searching, downloading, and exporting academic papers from 20+ scholarly sources including arXiv, PubMed, and Semantic Scholar. Supports multi-source concurrent search, citation network tracing, and export to CSV, RIS, and BibTeX.

Provides search functionality for arXiv.org papers through the official arXiv API, allowing users to search papers by keywords, filter by subject categories and date ranges, and receive comprehensive metadata including PDF links.

Enables agents to search, analyze, and explore arXiv academic papers with advanced multi-field search, author lookup, category browsing, citation extraction, and bibliography export.

Enables access to live precious metals prices, historical data, market intelligence, and portfolio management with AI/LLM integration.

Search 200M+ patents and scientific literature in natural language using PatSnap's global R&D intelligence database.

Gateway connector between LLM agents and world data, providing access to financial market prices, macroeconomic indicators, and news through a bundled endpoint catalog.

Enables searching scholarly literature across CrossRef, ERIC, Semantic Scholar, and OpenAlex, and retrieving open-access PDFs via Unpaywall.

Provides AI agents with Korean national fiscal data (budgets, settlements, and fiscal programs) from multiple government APIs through 7 tools, enabling natural language queries.

Enables to search academic papers in Japanese and English, inspect availability of full text, and download public PDFs locally.

Enables MCP clients to perform live Google searches and retrieve structured SERP data including organic results, AI Overviews, People Also Ask, AI Mode answers, news, shopping, and short-video results via eight read-only tools.

A standalone MCP server that searches multiple scholarly metadata providers (PubMed, Europe PMC, bioRxiv, Crossref, OpenAlex, Semantic Scholar, arXiv), deduplicates results, and returns ranked literature with optional open-access full-text retrieval from Europe PMC.

An MCP implementation that integrates the Brave Search API, providing comprehensive search capabilities including web, local business, image, video, news searches, and AI-powered summarization.

Installable MCP server for EU legal research with verifiable CELEX citations from the EUR-Lex corpus (DE/EN/FR).

Every other colour API tells you what goes together. Colour Memory tells you what it means, where the evidence ends, and what it must not claim. 47,515 hand-researched records, graded A–E, every result cited. 91 specialist tools built for agents that need precision, not guesses. Direct MCP: https://api.colourmemory.com/mcp — no signup, no key for the free tools (10 calls).