#!/usr/bin/env node
import { Server } from '@modelcontextprotocol/sdk/server/index.js';
import { StdioServerTransport } from '@modelcontextprotocol/sdk/server/stdio.js';
import {
CallToolRequestSchema,
ErrorCode,
ListToolsRequestSchema,
McpError,
} from '@modelcontextprotocol/sdk/types.js';
import { GitHubClient } from './github-client.js';
import { ListIssuesParams, ListPullRequestsParams } from './types.js';
const GITHUB_TOKEN = process.env.GITHUB_TOKEN;
if (!GITHUB_TOKEN) {
console.error('Error: GITHUB_TOKEN environment variable is required');
process.exit(1);
}
/**
* Validate parameters for listing issues
*/
const isValidListIssuesParams = (args: any): args is ListIssuesParams =>
typeof args === 'object' &&
args !== null &&
typeof args.owner === 'string' &&
typeof args.repo === 'string' &&
typeof args.since === 'string';
/**
* Validate parameters for listing pull requests
*/
const isValidListPullRequestsParams = (args: any): args is ListPullRequestsParams =>
typeof args === 'object' &&
args !== null &&
typeof args.owner === 'string' &&
typeof args.repo === 'string' &&
typeof args.since === 'string';
class GitHubLightweightServer {
private server: Server;
private githubClient: GitHubClient;
constructor() {
this.server = new Server(
{
name: 'github-mcp-lightweight',
version: '1.0.0',
},
{
capabilities: {
tools: {},
},
}
);
this.githubClient = new GitHubClient(GITHUB_TOKEN!);
this.setupToolHandlers();
// Error handling
this.server.onerror = (error) => console.error('[MCP Error]', error);
process.on('SIGINT', async () => {
await this.server.close();
process.exit(0);
});
}
private setupToolHandlers() {
// List available tools
this.server.setRequestHandler(ListToolsRequestSchema, async () => ({
tools: [
{
name: 'list_repository_issues',
description: 'List issues from a GitHub repository with minimal response size for efficient analysis',
inputSchema: {
type: 'object',
properties: {
owner: {
type: 'string',
description: 'Repository owner (username or organization)',
},
repo: {
type: 'string',
description: 'Repository name',
},
since: {
type: 'string',
description: 'Only show issues updated at or after this time (ISO 8601 format)',
},
},
required: ['owner', 'repo', 'since'],
},
},
{
name: 'list_repository_pull_requests',
description: 'List pull requests from a GitHub repository with minimal response size for efficient analysis',
inputSchema: {
type: 'object',
properties: {
owner: {
type: 'string',
description: 'Repository owner (username or organization)',
},
repo: {
type: 'string',
description: 'Repository name',
},
since: {
type: 'string',
description: 'Only show pull requests updated at or after this time (ISO 8601 format)',
},
},
required: ['owner', 'repo', 'since'],
},
},
],
}));
// Handle tool calls
this.server.setRequestHandler(CallToolRequestSchema, async (request) => {
const { name, arguments: args } = request.params;
try {
switch (name) {
case 'list_repository_issues':
if (!isValidListIssuesParams(args)) {
throw new McpError(
ErrorCode.InvalidParams,
'Invalid parameters for list_repository_issues. Required: owner (string), repo (string), since (string)'
);
}
const issues = await this.githubClient.getIssues(args.owner, args.repo, args.since);
return {
content: [
{
type: 'text',
text: JSON.stringify({
repository: `${args.owner}/${args.repo}`,
since: args.since,
total_issues: issues.length,
issues: issues
}, null, 2),
},
],
};
case 'list_repository_pull_requests':
if (!isValidListPullRequestsParams(args)) {
throw new McpError(
ErrorCode.InvalidParams,
'Invalid parameters for list_repository_pull_requests. Required: owner (string), repo (string), since (string)'
);
}
const pullRequests = await this.githubClient.getPullRequests(args.owner, args.repo, args.since);
return {
content: [
{
type: 'text',
text: JSON.stringify({
repository: `${args.owner}/${args.repo}`,
since: args.since,
total_pull_requests: pullRequests.length,
pull_requests: pullRequests
}, null, 2),
},
],
};
default:
throw new McpError(
ErrorCode.MethodNotFound,
`Unknown tool: ${name}`
);
}
} catch (error) {
if (error instanceof McpError) {
throw error;
}
// Handle other errors
const errorMessage = error instanceof Error ? error.message : 'Unknown error occurred';
return {
content: [
{
type: 'text',
text: `Error: ${errorMessage}`,
},
],
isError: true,
};
}
});
}
async run() {
// Test GitHub connection on startup
const isConnected = await this.githubClient.testConnection();
if (!isConnected) {
console.error('Failed to connect to GitHub API. Please check your GITHUB_TOKEN.');
process.exit(1);
}
const transport = new StdioServerTransport();
await this.server.connect(transport);
console.error('GitHub Lightweight MCP server running on stdio');
}
}
const server = new GitHubLightweightServer();
server.run().catch((error) => {
console.error('Failed to start server:', error);
process.exit(1);
});
