Vancouver

What is Vancouver?

Vancouver is an Elixir library that integrates the Model Context Protocol (MCP) into Phoenix/Bandit servers. It handles initialization, request validation, and provides helper functions to simplify creating MCP tools and prompts. It is for developers building MCP endpoints in their Phoenix applications.

How to use Vancouver?

Add {:vancouver, "~> 0.3"} to your mix.exs, implement tool and prompt modules using Vancouver.Tool and Vancouver.Prompt, configure the server name and version in config.ex, then forward the /mcp route in your router with your modules. Optionally, configure MCP clients like Claude Desktop via mcp-remote.

Key features of Vancouver

• Integrates MCP into Phoenix/Bandit servers.
• Handles initialization and request validation.
• Provides helpers for tools and prompts.
• Supports tools and prompts (sync responses only).
• Simple and extensible for custom needs.
• Published on Hex.pm for easy dependency management.

Use cases of Vancouver

• Expose custom MCP tools from your Phoenix application.
• Add MCP prompts for LLM interactions like code review.
• Integrate MCP server with Claude Desktop using mcp-remote.
• Build simple, synchronous MCP servers with Elixir.

FAQ from Vancouver

Does Vancouver support all parts of the Model Context Protocol specification?

Not yet. Vancouver currently supports tools, prompts, and sync responses (no streaming). The library is simple enough to modify for your needs.

Is Vancouver stable / ready for production?

No. This library is in early development and expects breaking changes.

Why is this library called Vancouver?

Vancouver is the natural home of MCP (Mountain, Coffee, Protocol).