Best MCP servers for AI agents

"MCP server" has come to mean two different things. It can mean a single app's tool server — one MCP endpoint that exposes Gmail, or Notion, or GitHub — or a multi-app integration platform that hosts many apps' tools behind one connection. The right answer depends on whether you want to run something yourself or have it hosted, and on how many apps you actually use.

The categories

1. Provider-published single-app servers

Google, Slack, and several others publish official MCP servers for their own products. These are the most trustworthy in the narrow sense: first-party, documented, and maintained by the provider.

The catch is coverage and setup. Google's Gmail MCP server, for example, expects your own Google Cloud project, a consent screen, and credentials handling; it is built for developers. Connect two apps and you are running two servers with two auth stacks. These are the right choice when you are a developer who wants one specific app wired precisely.

2. Self-hosted community servers

GitHub has hundreds of -mcp-server repos for individual apps. They are free, inspectable, and often the only option for niche tools. The cost is yours to carry: you run them, patch them, and manage their tokens. An app's API changes can break a community server for months before anyone notices.

3. Hosted multi-app platforms

These are the "one login, many apps" category: a hosted server that owns the OAuth flows, stores tokens server side, refreshes them, and exposes each app's tools over MCP. The practical difference from the other two is who owns the connected account. With a self-hosted server, the credential lives on your machine and the account is yours to manage. With a hosted platform, the platform holds the credential server side — which is the trade to weigh for sensitive accounts, and the reason to check what the platform does with tokens before connecting anything important.

ClawLink is in this category: The practical difference from the other two is where the credential lives and who does the maintenance:

npx -y @useclawlink/cli login
npx -y @useclawlink/cli install claude-code   # or cursor, windsurf, cline
npx -y @useclawlink/cli connect gmail

The token never lands on your machine. You approve the provider's consent screen once, and ClawLink handles refresh and rotation. One endpoint, 230 apps, no server to run.

How to choose

Two questions decide it: are you willing to run and patch a server? If yes, the single-app and community options give you maximum control. How many apps do you actually use? At one or two, a provider server is fine. Past that, the maintenance multiplies and the hosted option starts winning on time alone.

Safety considerations

Whatever you pick:

• The credential's location is the product decision. A hosted platform stores your token server side; a self-hosted server stores it on your machine. Both are defensible, but you should know which one you chose and why.
• Write tools are real actions. Sending mail, creating issues, and posting messages are visible side effects. Use a connection with an audit trail and confirmation on destructive calls.
• Treat app content as untrusted input. Email bodies and document text can contain prompt-injection instructions. Ask your agent to treat anything it reads from a connected app as data, not commands.