mcp-git

import TurndownService from 'turndown'; import type {McpServer, ToolCallback} from '@modelcontextprotocol/sdk/server/mcp.js'; import type {CallToolResult} from '@modelcontextprotocol/sdk/types.js'; import {z} from 'zod'; import type {ToolConfig} from '../types.js'; import {HTTP_FETCH_INPUT_SCHEMA, inputToRequestOptions, trimString, isHtmlContentType} from './common.js'; const MARKDOWN_ACCEPT_HEADER = 'text/markdown,text/x-markdown,application/markdown,text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8'; const BROWSER_USER_AGENT = 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.0.0 Safari/537.36'; const tds = new TurndownService({ headingStyle: 'atx', hr: '---', bulletListMarker: '-', codeBlockStyle: 'fenced', fence: '```', emDelimiter: '_', strongDelimiter: '**', linkStyle: 'inlined', linkReferenceStyle: 'full', }); // Add custom rules for better markdown conversion tds.addRule('strikethrough', { filter: ['del', 's'], replacement: (content) => `~~${content}~~`, }); tds.addRule('table', { filter: 'table', replacement: (content) => `\n${content}\n`, }); tds.remove(['head', 'script', 'style']); const MARKDOWN_FETCH_INPUT_SCHEMA = { ...HTTP_FETCH_INPUT_SCHEMA, start: z .number() .int() .min(0) .optional() .default(0) .describe('Start character position to return from the content, defaults to 0.'), end: z .number() .int() .positive() .optional() .describe('End character position to return from the content, defaults to content length.'), }; export class FetchMarkdownTool { get name() { return 'fetch-markdown'; } readonly config: ToolConfig<typeof MARKDOWN_FETCH_INPUT_SCHEMA, never> = { description: 'Fetch a URI over HTTP and convert HTML to markdown or return raw content with response metadata.', inputSchema: MARKDOWN_FETCH_INPUT_SCHEMA, annotations: { title: 'Fetch Markdown', readOnlyHint: false, openWorldHint: true, }, }; register(srv: McpServer) { srv.registerTool(this.name, this.config, this.#handle); } readonly #handle: ToolCallback<typeof MARKDOWN_FETCH_INPUT_SCHEMA> = async (input) => { const options = inputToRequestOptions(input); options.headers = new Headers(options.headers); if (!options.headers.has('Accept')) { options.headers.set('Accept', MARKDOWN_ACCEPT_HEADER); } if (!options.headers.has('User-Agent')) { options.headers.set('User-Agent', BROWSER_USER_AGENT); } const response = await fetch(input.uri, options); const originalContent = await response.text(); let outputContent = originalContent; const metadata: Record<string, unknown> = { status: response.status, statusText: response.statusText, headers: Object.fromEntries(response.headers.entries()), url: response.url, type: response.type, redirected: response.redirected, convertedToMarkdown: false, }; const result: CallToolResult = { content: [], }; // Get content type from response const contentType = response.headers.get('content-type'); const isHtmlContent = isHtmlContentType(contentType); if (isHtmlContent) { try { outputContent = tds.turndown(originalContent); metadata.convertedToMarkdown = true; } catch (error) { outputContent = originalContent; result.content.push({ type: 'text', text: `Markdown conversion failed, responding with original content.\nError: ${String(error)}`, }); } } else { // Add a note that conversion was skipped due to non-HTML content type result.content.push({ type: 'text', text: `Markdown conversion skipped: Content type '${contentType}' is not HTML.`, }); } if (input.start !== undefined || input.end !== undefined) { metadata.contentLength = originalContent.length; if (metadata.convertedToMarkdown) { metadata.markdownLength = outputContent.length; } outputContent = trimString(outputContent, input.start, input.end); } result.content.push( { type: 'text', text: JSON.stringify(metadata), }, { type: 'text', text: outputContent, }, ); return result; }; }