MCP Context Manager

Instructions

Implementation Reference

• src/retriever.ts:175-208 (handler)

  The actual implementation logic for get_file_summary tool.

  async getFileSummary(filePath: string): Promise<string> {
    const fileIndex = this.indexer.getFileIndex(filePath);
  
    if (!fileIndex) {
      return `File "${filePath}" not found in index.\nMake sure the file exists and the repository is indexed.`;
    }
  
    let summary = `File: ${filePath}\n`;
    summary += `Language: ${fileIndex.language}\n`;
    summary += `Lines: ${fileIndex.lines}\n`;
    summary += `Size: ${this.formatBytes(fileIndex.size)}\n\n`;
  
    if (fileIndex.imports.length > 0) {
      summary += `Imports (${fileIndex.imports.length}):\n`;
      summary += fileIndex.imports.slice(0, 10).map((imp) => `  - ${imp}`).join('\n');
      if (fileIndex.imports.length > 10) {
        summary += `\n  ... and ${fileIndex.imports.length - 10} more`;
      }
      summary += '\n\n';
    }
  
    if (fileIndex.exports.length > 0) {
      summary += `Exports (${fileIndex.exports.length}):\n`;
      summary += fileIndex.exports.map((exp) => `  - ${exp}`).join('\n') + '\n\n';
    }
  
    if (fileIndex.symbols.length > 0) {
      const byType = this.groupByType(fileIndex.symbols);
  
      for (const [type, symbols] of Object.entries(byType)) {
        summary += `${type}s (${symbols.length}):\n`;
        summary += symbols
          .map((s) => `  - ${s.name} (line ${s.line})${s.signature ? `: ${s.signature}` : ''}`)
          .join('\n');

• src/index.ts:239-252 (schema)

  Tool registration and schema definition for get_file_summary.

  {
    name: 'get_file_summary',
    description: '⭐ PREFERRED FOR FILE OVERVIEW: Get file structure (exports, functions, classes, imports) without reading full content. Use this INSTEAD OF Read when you need to understand what\'s in a file without seeing implementation details. Saves 90% tokens.',
    inputSchema: {
      type: 'object',
      properties: {
        filePath: {
          type: 'string',
          description: 'Path to the file relative to repository root',
        },
      },
      required: ['filePath'],
    },
  },

• src/index.ts:485-502 (registration)

  The request handler switch-case that calls the retriever.getFileSummary function.

  case 'get_file_summary': {
    const a = args as any;
    const filePath: string = a.filePath || a.path || a.file;
    if (!filePath) {
      return {
        content: [{ type: 'text', text: 'Error: filePath is required.' }],
        isError: true,
      };
    }
    const result = await retriever.getFileSummary(filePath);
    return {
      content: [
        {
          type: 'text',
          text: result,
        },
      ],
    };