Top communication MCP servers

Ranked by the composite AgentRank score — a weighted blend of stars (15%), freshness (25%), issue health (25%), contributors (10%), and inbound dependents (25%). Average score across all 892 communication tools is 34.2. The tools below are the category leaders.

Choosing by platform

Slack

korotovsky/slack-mcp-server leads the category at 64.9 with 1,448 stars. The key differentiator: it requires no elevated OAuth permissions. Most Slack MCP servers require Workspace Admin approval for channels:history or similar scopes. This one routes around the permission wall by using the Slack Apps API directly. Covers DMs, group DMs, GovSlack workspaces, and implements smart history fetch logic that avoids hitting rate limits. Written in Go — fast and low on dependencies.

Email sending (transactional)

resend/mcp-send-email scores 61.3 with 470 stars. If your use case is sending email from an agent workflow — notifications, confirmations, summaries — Resend's MCP is the cleanest path. It abstracts away SMTP configuration entirely and routes through Resend's sending infrastructure, which handles deliverability, DKIM, and bounce management. The tradeoff is Resend account dependency, but for most teams already using Resend that's a non-issue.

Email reading and sending (IMAP/SMTP)

ai-zerolab/mcp-email-server at 52.0 is the top protocol-native email server. Works with any IMAP/SMTP provider — Gmail, Outlook, Fastmail, self-hosted Postfix. Read threads, search inbox, draft and send messages. Active development (last commit March 2026) and 191 stars signal a healthy maintenance cadence. Use this when you need email access without routing through a SaaS vendor.

Email (modern JMAP protocol)

wyattjoh/jmap-mcp at 48.3 is worth attention if you're on a JMAP-capable provider (Fastmail, Cyrus IMAP). JMAP (JSON Meta Application Protocol, RFC 8620) is the successor to IMAP — it uses batch HTTP requests instead of binary commands, supports push notifications, and handles email and calendar in the same protocol. Lower stars (166) reflect niche deployment, not quality.

Microsoft Teams

InditexTech/mcp-teams-server scores 45.8 with 358 stars from a large enterprise contributor (Inditex, the company behind Zara). The server handles sending messages, listing channels, accessing meeting transcripts, and querying team membership. If your organization runs Teams, this is the most battle-tested MCP option available. Python implementation uses the Microsoft Graph API under the hood.

Multi-platform messaging gateway

forgeai-dev/ForgeAI at 45.4 takes a different approach: one self-hosted server that routes to WhatsApp, Telegram, Discord, Slack, and more. Early project (9 stars) but the architecture is compelling for teams that need cross-platform agent messaging without managing separate MCP servers for each platform. Self-hosted means credentials never leave your infrastructure.

Discord

Microck/discord.py-self-mcp scores 42.3. The Discord MCP ecosystem is fragmented — there's no dominant server with significant star momentum. This one uses discord.py-self to access DMs, guilds, and channels comprehensively. Note that self-bots operate in a gray area of Discord's ToS; use with a dedicated bot account rather than a personal account.

What to watch for

Why scores are lower in this category

Communication tools top out at 64.9 in the AgentRank index versus 85+ for developer tools and 80+ for database/infrastructure. The reason: most communication MCP servers are community projects, not official vendor releases. Official servers from Slack, Discord, or Microsoft would likely score in the 80s. Track this category — as vendors build official integrations (as Slack has begun with slackapi/slack-mcp-plugin), scores will rise and options will improve.

OAuth and data sensitivity

Communication tools handle the most sensitive data in your agent stack — email threads, Slack messages, internal discussions. Every server in this list uses OAuth or API keys for auth. Before deploying, review what scopes you're granting and whether the server stores tokens at rest. The korotovsky Slack server's no-elevated-permissions design is genuinely meaningful security-wise: you're not handing an agent read access to every channel in your workspace.

Rate limits and API quotas

Slack's API enforces per-minute and per-day request limits. Gmail/IMAP providers enforce concurrent connection limits. Agents that loop on messaging APIs in tight cycles will hit these limits quickly. Design workflows with explicit delays between message reads, or use webhook-based triggers (when supported) rather than polling.