"Search for free open-source software" matching MCP servers:

Enables AI CLI agents to interact with WhatsApp using an unofficial multi-device API, supporting messaging, chat/group/channel management, statuses, and an AI-driven inbox without requiring an official API key.

Enables ChatGPT to search, read, send, and organize email in a self-hosted inbox through private MCP tools.

Enables full-text search of macOS iMessages including link preview metadata. Works as an MCP server for Claude Desktop to search your messages locally.

Enables searching Telegram messages and chats, retrieving recent messages, and extracting text from attached documents (PDF, TXT, MD, CSV) using your personal Telegram account.

Provides MCP-compatible AI clients with full access to a Flarum forum's API, enabling reading, searching, creating discussions, replying, moderation, and management of users, tags, and groups.

A standalone remote MCP server that lets AI clients read, search, post, schedule, and manage messages and files in Mattermost as each individual user through per-user OAuth, without requiring a plugin or Enterprise license. It keeps each user's Mattermost tokens server-side, enforces per-user permissions and API limits, and ships guard rails against duplicate or unintended posts.

Enables AI apps on the local computer to search and read Thunderbird mail, organize messages, manage contacts, and prepare drafts, with optional controlled sending. Access is limited to user-selected accounts and tool groups, with local-only communication and a pause control.

Enables ChatGPT and Codex to interact with Zoho Mail through Zoho's official MCP service, with safe workflows and capability boundaries.

Shows your current Claude Desktop activity as Discord Rich Presence, including model, status, usage, and subscription info.

Enables searching and retrieving messages across Slack workspaces using Slack's search API. Supports pagination, filtered results, and returns message details including text, timestamps, users, channels, and permalinks.

Enables AI assistants to manage multiple Outlook/Microsoft 365 mailboxes simultaneously through MCP tools, with local OAuth token storage.

Enables reading and sending messages in Google Messages for web through a paired Chrome tab using chromefile, with tools for status, listing conversations, reading message history, and sending texts.

Enables Claude to check, search, read, and organize email across multiple Spacemail (Spaceship) inboxes, and to compose threaded drafts or replies that are saved to Drafts for review before sending. Optional direct sending, safe move-to-Trash instead of permanent deletion, and keychain-backed credentials keep the workflow private and controlled.

23 tools for AI agents working with Nostr Open source. No API key. No account. NIP-46 remote signing Publish notes, reply, react, repost Encrypted DMs (NIP-04 + NIP-44) Fetch events, profiles, social graph

Brings live project context into Slack via MCP, enabling developer teams to check service health, recall team decisions, search code, and query project context directly from chat.

A self-hosted WhatsApp gateway that exposes messaging capabilities via MCP, allowing AI agents to send, receive, and manage WhatsApp messages through a single-command setup with SQLite storage.

Enables AI assistants to book meetings, check availability, and manage Cal.com scheduling through natural conversation.

Enables AI assistants to interact with Slack workspaces by listing channels, posting messages and thread replies, adding emoji reactions, retrieving channel history and thread replies, and inspecting user profiles. Supports both stdio and Streamable HTTP transports for flexible integration.

Enables permission-checked search of past chat history that links older messages with the latest activity, returning supporting context such as timestamps, speakers, and surrounding conversation. Authorization is re-verified against current room membership and approved groups on every search, message fetch, and period read.

Enables Claude to interact with WhatsApp on macOS through the Model Context Protocol. It allows reading messages, searching contacts, listing chats, and sending replies via natural conversation.

MCP server for SentVia that provides email infrastructure for AI agents, enabling them to create inboxes, send, reply, forward, search messages, manage drafts, domains, webhooks, and allow/block rules through 21 tools.

Enables AI apps to read a student's courses, due dates, grades, missing work, announcements, modules, discussions, syllabus, and calendar events in a read-only way. It cannot submit, edit, or delete anything, and credentials go only to the user's own school.

An MCP server that enables concurrently-running Claude Code sessions to cross-talk via channels, DMs, and leader coordination, all backed by a shared beads database.

Open end-to-end encrypted messaging protocol and MCP server (a4a-mcp) that gives AI agents a cryptographic address (apub1...) to exchange messages, tasks, and signed agreements directly across NAT without port forwarding.

A Model Context Protocol server implementation that enables AI assistants to interact with Slack workspaces, allowing them to browse channels, send messages, reply to threads, add reactions, and retrieve user information.

An MCP server that enables users to search for government grants based on keywords and view detailed information including funding, eligibility, and deadlines.

Connects MCP clients to a telephony account so users can manage phone numbers, SIP accounts, routing, SMS, calls, and billing in plain language. It exposes search, schema lookup, and execute tools to run permitted API operations, with confirmation required for paid or destructive actions.

A remote Model Context Protocol server for Feishu (Lark) that supports OAuth authentication and deployment on Cloudflare Workers. It allows AI clients to interact with Feishu documents, perform content searches, and manage document blocks with a zero-configuration experience.

Connects a single Mail.ru mailbox to ChatGPT through Google OAuth and IMAP, enabling folder listing, email search, non-destructive reading, moving messages, and moving selected messages to the trash.

Provides access to personal/team knowledge repositories with tools to search, retrieve, and save information from various sources including Slack, Gmail, and document storage platforms.

Connect Claude Desktop to WhatsApp. Send & receive messages, manage groups, share media — all through natural conversation with Claude.

Enables MCP-capable models to read QQ messages, reply in group and private chats, send images and favorite stickers, poke users, and manage pacing, deduplication, and concurrency during ongoing chat tasks through a local SnowLuma OneBot interface.

Enables AI agents to automate the Viber desktop client on Linux by searching contacts, opening chats, reading conversation history, preparing verified drafts, and sending operator-approved messages.

Enables reading and sending iMessages through Poke via a local Mac server, with tools for chat management and message history.

Enables Claude Desktop on Windows to search and read Yahoo Mail messages in read-only mode, without sending, deleting, or otherwise modifying them.

Enables users to drive a Claude Code session from chat messages on a linked phone number or an official business account, with bidirectional text and media, local voice-note transcription, per-chat personalities, pairing-code access control, and tool-approval by emoji reaction. It also supports polls, scheduled tasks, and context recovery after restarts for other stdio MCP clients.

Enables AI agents to interact with Slack through 20 specialized tools and resources for managing channels, messages, users, and files. It features built-in rate limit handling, safety controls for message sending, and full support for Slack Block Kit formatting.

A read-only, local MCP server that enables Claude Desktop and Claude Code to brief users on selected WhatsApp chats, surfacing mentions, urgent items, follow-ups, bills, and payment screenshots through local OCR while keeping data encrypted on the user's PC.

A Model Context Protocol server providing file search and question tools for AI models. Enables keyword search in files with line numbers and integration with external chat services.

Enables AI assistants to manage WhatsApp instances, send and receive messages, run campaigns, configure webhooks, manage team members, and view metrics through OAuth-secured MCP tools, with optional message replies on the user's behalf.