"Open Source Intelligence (OSINT) tools and techniques" matching MCP servers:

An open engine that gives AI persistent, reusable UI components with a writable component registry, versioned data storage, and a shell runtime, enabling AI to create, save, and reuse single-purpose apps.

repo-release-tools mcp-server automates the software release process by managing version bumps, changelog generation, and releases. It streamlines repository maintenance by handling repetitive release tasks directly through your AI assistant.

Open Ephemeris is a high-precision astrology API with an MCP server exposing 116+ endpoints across natal charts, transits, synastry, Human Design, BaZi, solar returns, and much more.

Serves Claude Desktop a unified, actionable read of Google Calendar and Google Tasks, surfacing overdue items first, then the day's events, free slots, and open tasks, with explicit-request-only write tools for creating, updating, completing, and deleting. Google stays the sole source of truth with no server-side storage beyond the OAuth token and a 30-second read cache.

MCP server for Threadlinqs Intelligence — 49 tools across threat intelligence, detections, IOCs, threat actors, MITRE attack-chains, C2 infrastructure, and Purple-tier composite intelligence. Drop-in for Claude Code, Claude Desktop, Cursor, and any MCP-compatible client.

Full-stack PDF intelligence MCP server for extracting, manipulating, annotating, converting, validating, and RAG-searching PDFs through a unified tool surface and React workbench.

MCP server for Proofpoint Email Protection - email security, threat intelligence, TAP (Targeted Attack Protection), and email filtering API integration

Open-source MCP server that lets AI agents control 3D printers. 353 tools for OctoPrint, Moonraker, Bambu Lab, Prusa Link, and Elegoo — search model marketplaces, generate 3D models from text, slice STL files, queue prints, monitor with camera vision, and manage multi-printer fleets. Install via pip install kiln3d.

MCP server that resolves postal/ZIP codes to place names, states, and coordinates using Zippopotam.us. Free, no API key required.

Enables real-time domain registration lookups via RDAP, including availability, expiration, and registrar details, with no API key required. Supports natural language queries like 'is example.com available?' or 'when does example.com expire?'.

MCP server for creating and editing diagrams using draw.io. Allows generating diagrams from Mermaid or XML, searching shapes, and opening them in draw.io for export.

Enables users to draw GIS geometry on an interactive map and get clean, validated GeoJSON to hand off to other GIS MCP servers such as FEMA flood screening and USGS hydrography.

Gives Claude read-only access to your ESPN fantasy football team, including roster, weekly matchup, free agents, and player profiles.

Vacation rental software. A signed stay offer on the host's own domain. Agents discover a host domain, verify an Ed25519-signed offer (VRP), and send the guest to that domain to book and pay the host. Do not compare hosts or prices. HemmaBo + VRP, 6 runtime tools: 2 HemmaBo tools, 2 host onboarding tools, and 2 VRP verification tools. Not an OTA. Not a marketplace.

Local-first crypto portfolio aggregation across exchanges (Bybit, Binance), EVM and Solana wallets, and Polymarket. Read-only credentials, runs as a local MCP server. Data aggregation only, not financial advice.

MCP server that lets agents create, display, and export rich UI widgets (cards, dashboards, charts, forms) inline in conversations, with interactive iframe support in MCP Apps hosts and PNG image fallback for other clients.

Enables currency conversion and exchange rate lookups using real ECB reference rates, free and without an API key. Supports natural language queries like 'convert 100 USD to EUR' or 'what's the exchange rate between GBP and JPY?'.

Provides real, official public holiday data for ~100 countries with tools to list holidays for a year and check if a specific date is a holiday. Free, no API key required, powered by Nager.Date.

Enables AI assistants to read, search, and traverse your entire reMarkable library, including handwritten notes via OCR.

Provides live product search, offer comparison, and price history retrieval from BestPrice.gr through three read-only tools, enabling AI applications to query shopping data without an API key.