"Free Graph and Network Visualization Tools (No API Key Required)" matching MCP servers:

Provides tools for AI-powered graph analysis, including relationship extraction, adjacency matrix creation, and network centrality calculations. It enables users to perform complex structural analysis and generate interactive D3.js visualizations from structured data.

Enables free keyword research by pulling autocomplete suggestions, Google Trends, Bing search volume, Reddit threads, and competitor sitemaps, with volume estimation and keyword organization for use in Claude, Cursor, and other MCP clients.

Enables natural-language spatial analysis of transmission lines and wildlife/public access lands using Claude, MCP, and DuckDB. Users can ask questions about intersections, distances, buffers, and other GIS operations without writing SQL.

Enables LLMs to perform OSINT link-analysis by exposing transforms (DNS, WHOIS, Shodan, etc.) as MCP tools for autonomous investigation and graph enrichment.

Enables access to Japanese stock market data via the free J-Quants API, providing tools for company search, daily quotes, and financial statements.

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.

Enables anonymous, read-only lookup of IP representatives, their profiles, market snapshots, and coverage statistics drawn from a completed static IPRATE data release. Queries are rate limited and served from immutable, checksum-verified release snapshots, so no database or live export tree is ever queried.

Verified AI free-tier limits, quota comparisons, commercial-use verdicts and zero-cost workflows. Every entry carries a human-checked verification date and is re-checked by a daily link patrol.

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

Provides actionable financial intelligence tools for AI agents including insider buying signals, earnings IV plays, market pulse, stock analysis, and options strategies via free public data sources.

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).

An MCP-native pipeline for collecting structured intelligence on higher education institutions using the WHED schema, enabling scraping, extraction, validation, and saving of profiles.

An MCP server for HF radio propagation analytics using the IONIS dataset collection, enabling natural language queries about band conditions, propagation paths, and solar correlations.

Enables querying MITRE ATT&CK and D3FEND data efficiently, providing techniques, detections, mitigations, actors, and countermeasures with token-aware summaries and paginated graph traversal.

An MCP server that provides comprehensive financial insights and analysis by leveraging real-time market data, news, and advanced analytics for stocks, options, financial statements, and economic indicators.

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.

Live normalized remote-job data across 5 boards — one keyless endpoint, one schema, skill fit-score. No API key required. Tools: search jobs by skills + salary floor, live market stats, and computed salary bands.

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

Presents a plausible, tool-rich workspace surface — file reading, credential listing, command execution, database queries, and configuration retrieval — that returns only synthetic results while logging every connection, tool call, and argument received. It enables researchers to measure what MCP clients and agents actually do when handed dangerous-sounding tools, including whether they follow injected instructions or complete a retrieve-then-use credential chain.

Enables users to describe a project in an MCP client and work through pre-submission grant phases, including finding fitting programs, checking eligibility and blockers, pulling precedent from past awards, shortlisting, and drafting memos, budgets, and submission checklists. Coverage is full for US grants and partial (discovery and precedent only) for Canada, with no win-odds estimates or post-award reporting.