Rust MCP Core

cargo new my-mcp-server
cd my-mcp-server

# Add to Cargo.toml:
# [dependencies]
# rust-mcp-core = "0.1"

# Or from GitHub:
# rust-mcp-core = { git = "https://github.com/nullablevariant/rust-mcp-core" }

use rust_mcp_core::{load_mcp_config_from_path, runtime, PluginRegistry};

#[tokio::main]
async fn main() -> Result<(), rust_mcp_core::McpError> {
    let config = load_mcp_config_from_path("config/mcp_config.yml".into())?;
    runtime::run_from_config(config, PluginRegistry::new()).await
}

version: 1
server:
  host: 0.0.0.0
  port: 3000
  endpoint_path: /mcp
  transport:
    mode: streamable_http
  auth:
    enabled: false
  logging:
    level: info

upstreams:
  api:
    base_url: ${env:API_BASE_URL}

tools:
  items:
    - name: api.list_items
      description: List items from the upstream API
      input_schema:
        type: object
        properties:
          query:
            type: string
      execute:
        type: http
        upstream: api
        method: GET
        path: /items
        query:
          q: "${query}"

# Default build (streamable HTTP included)
cargo build --release

# Minimal build: stdio transport only
cargo build --release --no-default-features

# Selective features
cargo build --release --no-default-features --features http_tools,auth,prompts

{
  "mcpServers": {
    "my-rust-server": {
      "command": "/path/to/my-mcp-server/target/release/my-mcp-server",
      "args": [],
      "env": {
        "API_BASE_URL": "https://api.example.com"
      }
    }
  }
}