@mcp-weave/core

Core functionality for MCP-Weave - the TypeScript framework for building Model Context Protocol (MCP) servers.

Installation

npm install @mcp-weave/core
# or
pnpm add @mcp-weave/core

Features

• Spec Types - TypeScript types and Zod schemas for MCP specifications
• Parser - Parse MCP spec files (YAML/JSON)
• Validator - Validate MCP specifications
• Scanner - Extract metadata from decorated classes
• Generator - Generate MCP server code from specs

Usage

Spec Types

import type { McpSpec, ToolDefinition, ResourceDefinition } from '@mcp-weave/core';

const spec: McpSpec = {
  version: '1.0',
  server: {
    name: 'my-server',
    version: '1.0.0',
  },
  tools: [
    {
      name: 'hello',
      description: 'Says hello',
      inputSchema: {
        type: 'object',
        properties: {
          name: { type: 'string' },
        },
      },
    },
  ],
};

Parser

import { parseSpec, parseSpecFromFile } from '@mcp-weave/core';

// Parse from string
const spec = parseSpec(`
version: "1.0"
server:
  name: my-server
  version: "1.0.0"
tools:
  - name: hello
    description: Says hello
`);

// Parse from file
const specFromFile = await parseSpecFromFile('./mcp.yaml');

Validator

import { validateSpec, ValidationError } from '@mcp-weave/core';

try {
  validateSpec(spec);
  console.log('Spec is valid!');
} catch (error) {
  if (error instanceof ValidationError) {
    console.error('Validation errors:', error.errors);
  }
}

Scanner (Metadata Extraction)

import { extractMetadata, METADATA_KEYS } from '@mcp-weave/core';

// Extract metadata from a decorated class
const metadata = extractMetadata(MyDecoratedClass);

console.log(metadata.server); // Server metadata
console.log(metadata.tools); // Tool definitions
console.log(metadata.resources); // Resource definitions
console.log(metadata.prompts); // Prompt definitions

Generator

import { generateServerCode } from '@mcp-weave/core';

const code = generateServerCode(spec, {
  language: 'typescript',
  framework: 'standalone',
});

console.log(code);

API Reference

Types

| Type | Description | | -------------------- | ------------------------------------ | | McpSpec | Complete MCP specification | | ToolDefinition | Tool definition with input schema | | ResourceDefinition | Resource definition with URI pattern | | PromptDefinition | Prompt definition with arguments | | ServerConfig | Server configuration | | TransportConfig | Transport configuration |

Functions

| Function | Description | | -------------------- | ------------------------------------- | | parseSpec | Parse spec from YAML/JSON string | | parseSpecFromFile | Parse spec from file path | | validateSpec | Validate an MCP spec | | extractMetadata | Extract metadata from decorated class | | metadataToSpec | Convert metadata to MCP spec | | generateServerCode | Generate server code from spec |

Requirements

• Node.js >= 18
• TypeScript >= 5.0 (for TypeScript users)

Related Packages

• @mcp-weave/nestjs - NestJS-style decorators
• @mcp-weave/testing - Testing utilities
• @mcp-weave/cli - Command-line interface

License

MIT