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

Enables AI assistants to search, read, and cite Title 38 of the Code of Federal Regulations from a locally built SQLite full-text index, using read-only tools for ranked regulation search, full section retrieval, hierarchy browsing, part listing, and index freshness/health checks. All queries run offline against the local index, returning ranked hits with citations, snippets, cross-references, and staleness notices.

MCP server for Statistics Norway (SSB) PxWebApi, enabling table metadata queries via a single tool.

Access Norway's official business register (Brønnøysund Register Centre) via MCP, enabling queries and integration with AI agents.

Provides access to the Norwegian Parliament's open data via Stortinget's API, enabling querying of parliamentary information through natural language.

Free Polish VAT invoice generation MCP server with PDF output and preview. No API key required.

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 querying the SEC Ownership Graph, providing curated read-only tools to analyze activist campaigns, control chains, and board interlocks from SEC filings. Answers cite accession numbers and abstain when data is insufficient.

Verified Singapore property, tax, affordability, salary, and location data for AI agents. 17 MCP tools, x402 micropayments, source provenance on every response. Singapore live now, more markets coming. Categories: Finance, Real Estate, Data, Singapore, x402, Payments, Government Data

Provides tools to retrieve and validate Goods and Services Tax (GST) details using GST numbers, PAN cards, or company names. It enables users to check registration status, filing history, and business addresses directly through the GST Insights API.

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 and retrieving German public procurement notices as normalized JSON, with per-call payment via x402 (USDC on Base) and free sample and stats tools.

Provides access to 529,000+ US statute sections across all 50 states and federal codes for comprehensive legal research. Supports semantic search, citation graph traversal, jurisdictional comparisons, and regulatory risk analysis through natural language queries.

Enables evidence-driven motor-carrier search, qualification, risk assessment, monitoring, and TMS integration directly from Claude Code and MCP clients.

MCP server for Azerbaijan's official legal-acts database (e-qanun.az), enabling search, metadata retrieval, and full-text access to legislative and judicial documents.

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.

Enables keyless, read-only access to a wide range of public APIs (including weather, elevation, Japanese addresses, environment, science, and civic data) through MCP clients, with usage limits and abuse protection built in.

An MCP server that enables interaction with Google's Fact Check Tools API, allowing users to query and manage fact-check claims and publishers through natural language commands.

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 trademark clearance and research across EU and Benelux registers, plus company, group-structure, and EU VAT lookups, all through free public sources without API keys.

A Model Context Protocol server that connects AI assistants to Brazilian public data services, providing access to postal codes, company registrations, bank information, area codes, IBGE data, currency exchange rates, and domain registration status.