MCP Server

What is MCP Server?

MCP Server is a Dart plugin for implementing Model Context Protocol (MCP) servers. It allows Flutter applications to expose data, functionality, and interaction patterns to Large Language Model (LLM) applications in a standardized way.

How to use MCP Server?

Install the package and create a Server instance with a name, version, and capabilities. Add handlers for tools, resources, and prompts, then connect to a transport (stdio, SSE, or Streamable HTTP). Use the simplified McpServer.createAndStart API or the classic connect method. Configuration of transports is done via TransportConfig objects.

Key features of MCP Server

• Multi-revision MCP support with per-version capability gating
• Core primitives: Resources, Tools, Prompts, and Completions
• Server-initiated requests (sampling, roots, elicitation)
• OAuth 2.1 Resource Server (RFC 9728) with Bearer token validation
• Structured tool output and resource links (2025-06-18+)
• Icons on tools, resources, and prompts (2025-11-25)
• List-changed notifications and progress/cancellation support
• Multiple transports: stdio, SSE, Streamable HTTP
• Cross-platform: Android, iOS, web, Linux, Windows, macOS

Use cases of MCP Server

• Expose application data to LLMs via static or templated resources
• Give LLMs the ability to perform actions with tools (e.g., calculators, file access)
• Provide reusable prompt templates that guide LLM interactions
• Build custom MCP servers that integrate with existing Dart/Flutter apps