Top 7 MCP Servers for Communication & Collaboration in 2026

Why communication MCP servers matter — and why the grade matters more

Messaging, email and project tools are where an AI agent stops being a chatbot and starts doing real work: triaging a Slack thread, sending a transactional email, filing a ClickUp task, or drafting an SMS blast through Twilio. The Model Context Protocol (MCP) is what makes that possible — a single standard that lets an assistant read and write across all of these platforms. It is also the fastest-growing corner of the AI tooling ecosystem, which means new servers appear weekly and the quality bar is wildly uneven.

That is the problem this list solves. Every server below has been scanned by MCP Trust Checker, our deterministic security engine, so you see a real MCP Trust Score — an A–F grade from 0 to 100 — next to each one, not just a GitHub star count. Grades are easy to read: A means the published package is clean and the capabilities it requests are well-scoped; lower grades or high-severity findings mean there is something you should look at before you hand the server your credentials. A high star count tells you a project is popular. The grade tells you whether it is safe to plug into an agent that can read your inbox.

We ranked these seven by real-world adoption first and grade second — this is a "top servers" list, not a leaderboard of perfect scores. Where our scan flags something, we say so plainly and link you to the finding.

1. Slack MCP Server (korotovsky)

This is the de facto standard Slack integration for AI agents and the top-ranked Slack entry on the major MCP directories. It connects an assistant to your workspace to read channels, threads and DMs, search history and post messages, with smart history fetching and both stdio and SSE transports. Its standout feature: it works without creating a bot or getting admin-approved workspace permissions, which is why it has roughly 1.7k GitHub stars and dominates the category.

It earns a top score, but our scan does flag one high-severity finding tied to its broad workspace access — worth a two-minute review on the registry page before you connect it, since this server can read everything you can read in Slack.

MCP Trust Score: A (100/100) · GitHub · npm

2. Gmail MCP Server (GongRzhe)

One of the most-installed email servers in the whole ecosystem, at roughly 24k weekly npm downloads. It gives an assistant natural-language control over Gmail — sending, reading, searching and organizing mail — with attachment handling, label management and batch operations. The reason it is so widely adopted is the automatic OAuth setup: it opens a browser, walks you through Google's auth flow, and caches the credentials locally, so there is almost no configuration friction.

Our scan gives it a clean bill of health with no high-severity findings and a minimal, well-scoped capability profile — an easy recommendation for outbound and inbox automation.

MCP Trust Score: A (100/100) · GitHub · npm

3. Notion MCP Server (official)

Notion's own official server is ubiquitous on awesome-lists for good reason: it lets an agent search, read, create and update pages and databases across a workspace, and it works with content as Markdown instead of raw block JSON, which keeps token usage down. It supports both stdio and Streamable HTTP transports with per-connection token passthrough, making it a solid backbone for knowledge-base and documentation workflows.

Be honest with yourself about the grade here: this is the lowest-scoring server on the list. Our scan gives it a B (85/100) and flags two high-severity findings, consistent with its broad, high capability level. That does not mean don't use it — it is the official vendor build — but review those two findings on its registry page before you grant it write access to a workspace that holds sensitive docs.

MCP Trust Score: B (85/100) · GitHub · npm

4. Discord MCP Server (barryyip0625)

The most actively developed Discord integration and the one with the highest directory traffic. It lets AI clients send and read messages, manage channels, handle webhooks, and — unusually for a Discord server — create and manage forum posts. That forum support makes it a genuine fit for community management and moderation automation rather than just posting notifications. It ships with both stdio and HTTP transports.

The scan is clean: an A grade, no high-severity findings, and a minimal capability footprint.

MCP Trust Score: A (100/100) · GitHub · npm

5. Twilio MCP Server (twilio-labs)

Twilio's official monorepo exposes the company's full API surface as MCP tools — SMS and MMS messaging, voice, and Conversations — so an agent can send programmable messages and drive real telephony workflows using your Twilio account credentials. If you want an AI system that can actually text a customer or place a call, this is the reference implementation from the platform that defines the category.

It scores an A with no high-severity findings and a minimal capability level. Note the package is still on an alpha track (@twilio-alpha/mcp), so pin your version and watch releases.

MCP Trust Score: A (98/100) · GitHub · npm

6. Resend MCP Server (official)

Resend's official server is a clean, focused way to give an agent outbound email — both transactional and marketing. It can compose and send emails with attachments and manage contacts, broadcasts and domains directly from any MCP client. Where the Gmail server is about working inside a personal inbox, Resend is the better choice when you want an application-grade sending pipeline behind your agent.

It earns a perfect score in our scan: no high-severity findings, minimal capabilities.

MCP Trust Score: A (100/100) · GitHub · npm

7. ClickUp MCP Server (taazkareem)

The most popular ClickUp bridge on npm, this server connects an assistant to ClickUp for team task and project collaboration — creating, retrieving and updating tasks, lists, folders and workspaces through natural language. It is the go-to option for teams that want to drive their project-management workspace from an agent instead of clicking through the UI.

Our scan returns an A with no high-severity findings and a minimal capability profile.

MCP Trust Score: A (100/100) · GitHub · npm

How we graded these

Every score above comes from the MCP Trust Checker engine, which is deterministic and open-source. It downloads the actual published npm or PyPI package — the same code your machine would install — and statically analyzes its capabilities, permissions and toxic-flow patterns against a fixed set of rules. There is no LLM in the loop and no subjective judgment: the same input always produces the same score, so the grade you see is reproducible and auditable. That is the difference between a security scan and a vibe. You can read the methodology and browse every scanned server on the Trust Registry.

Want the rest of the category, including servers that didn't make this shortlist? Browse the full Communication & Collaboration category in the registry, and if you're evaluating a package that isn't listed yet, scan any npm or PyPI MCP server for free through the MCP Trust Checker API before you connect it to your agent.

npx mcptrustchecker