"Services or tools available for free without requiring an API key" matching MCP servers:

An MCP server that connects AI assistants to YNAB budgets, enabling natural language queries about finances backed by full API coverage and built-in YNAB methodology knowledge.

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

Model Context Protocol (MCP) server providing real-time institutional Spot Bitcoin (BTC) and Ethereum (ETH) daily net flow metrics for AI agents.

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.

Real-time crypto, stock, and prediction-market data for agents — prices, indicators, funding rates, DeFi TVL, macro calendar, and an AI momentum score. Configure one Base wallet key and it just works. No signup, no dashboard, no subscription.

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

Bitcoin data for AI agents. Pay-per-query via x402 micropayments. No API keys. No subscriptions. No tokens.

Defeatbeta API is an open-source alternative to Yahoo Finance's market data APIs, designed to provide reliable and high-performance financial data.

55+ pay-per-call tools for AI agents over MCP: live telemetry, blockchain/on-chain checks, environmental, transit, finance, and network utilities. No API key or signup — agents pay per request with x402 USDC micropayments (Base and Solana).

An unofficial, read-only MCP server for Sarwa Odyssey that provides portfolio, holdings, transactions, watchlists, and agent snapshots via deterministic JSON documents.

Provides access to measured x402 ecosystem data, allowing users to query which merchants actually accept payment (verified by real on-chain settlements) and explore market concentration and health statistics.

Provides Korean-specific financial calculators (4 insurances, salary net, severance pay, capital gains tax, DSR/DTI, FX conversion, housing subscription score) as MCP tools for AI agents.

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.

MCP server for pay-per-call DeFi and crypto data via x402 micropayments on Base. 8 endpoints: token prices, TVL, funding rates, token security, gas tracker, whale monitoring, wallet profiling, and yield scanning.

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

MCP server for querying cryptocurrency portfolio data, transaction history, net worth, and historical snapshots across 20+ blockchains via the Octav API.

Enables access to current inflation data including monthly and annual inflation percentages using CPI (Consumer Price Index) or HICP (Harmonized Index of Consumer Prices) indicators through the API Ninjas Inflation API.

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

A local MCP server that automatically generates tools from Toss Securities' official OpenAPI spec, enabling real API calls with multi-layered order safety and OAuth 2.0 authentication.

A small MCP server that wraps MoneyMoney on macOS via AppleScript, exporting account lists and transactions (bookingDate, amount, name, purpose) as plists for invoice reconciliation, complementing a companion Apple Mail server.