An agent that can only talk is of little use. It gets interesting the moment it works inside your real software. The connecting piece for that is called MCP.
MCP stands for Model Context Protocol, an open standard released by Anthropic in November 2024. It defines a single, uniform way for an AI agent to talk to external programs, data sources and services. Think of it as a USB-C port for AI: one standard connector that any compatible tool can plug into, instead of building a separate custom solution for every application.
In practice this means: with MCP, an agent can actually act inside your tools, for example look up an invoice in Stripe, create a ticket in Linear, or read and write a document in Notion. The provider supplies an MCP server for this, and your agent connects to it as a client.
Connections today run mostly over OAuth, the same secure sign-in you know from „Sign in with Google“. Your credentials never end up in a config file, and you grant access to exactly what the agent may reach. The clear trend is toward remote servers that connect via a URL in minutes, with no local installation at all.
Check before connecting. MCP servers are a real attack surface. Only connect services you trust, and read their privacy and terms first. Third-party servers are explicitly not reviewed or endorsed by Anthropic.
Providers with an official, hosted remote server. Click a name to open its official connection guide.
For everyday use, plus a few reference servers as building blocks. Click a name to open the guide.
Each link points to the provider's official connection guide. Fetch and Filesystem are reference servers maintained by Anthropic and the MCP steering group as examples, explicitly not intended as production-ready solutions. The Financial market data entry stands for a whole category of several providers and therefore links to a directory.
The total number of available servers is far larger, with one major directory listing over 17,000 entries. Most of those are community-built and unvetted. This list deliberately sticks to official, hosted providers.
Data as of Summer 2026. Sources include: Anthropic (Model Context Protocol), Claude Platform Docs, mcpservers.org, and the providers' official documentation.