Terminal Reader MCP

Instructions

Implementation Reference

• index.js:118-147 (handler)

  Handler function for the 'get_last_error' tool. It parses the log, checks if the last command failed (non-zero exit code), and returns the command, exit code, and output if there was an error; otherwise, indicates success or no history.

  async () => {
    const entries = parseLogFile();
    
    if (entries.length === 0) {
      return {
        content: [{
          type: 'text',
          text: 'No terminal history found.',
        }],
      };
    }
  
    const last = entries[entries.length - 1];
    
    if (last.exitCode === 0 || last.exitCode === null) {
      return {
        content: [{
          type: 'text',
          text: 'Last command succeeded - no error to report.',
        }],
      };
    }
    
    return {
      content: [{
        type: 'text',
        text: `Command: ${last.command}\nExit Code: ${last.exitCode}\n\nError Output:\n${last.output}`,
      }],
    };
  }

• index.js:113-117 (schema)

  Schema and metadata definition for the 'get_last_error' tool, including title, description, and empty input schema.

  {
    title: 'Get Last Error',
    description: 'Get the last terminal command only if it failed (non-zero exit code). Returns nothing if the last command succeeded.',
    inputSchema: {},
  },

• index.js:111-148 (registration)

  Registration of the 'get_last_error' tool using server.registerTool, including the tool name, schema, and inline handler function.

  server.registerTool(
    'get_last_error',
    {
      title: 'Get Last Error',
      description: 'Get the last terminal command only if it failed (non-zero exit code). Returns nothing if the last command succeeded.',
      inputSchema: {},
    },
    async () => {
      const entries = parseLogFile();
      
      if (entries.length === 0) {
        return {
          content: [{
            type: 'text',
            text: 'No terminal history found.',
          }],
        };
      }
  
      const last = entries[entries.length - 1];
      
      if (last.exitCode === 0 || last.exitCode === null) {
        return {
          content: [{
            type: 'text',
            text: 'Last command succeeded - no error to report.',
          }],
        };
      }
      
      return {
        content: [{
          type: 'text',
          text: `Command: ${last.command}\nExit Code: ${last.exitCode}\n\nError Output:\n${last.output}`,
        }],
      };
    }
  );

• index.js:29-76 (helper)

  Helper function parseLogFile() that parses the terminal log file into structured command entries (command, output, exitCode), used by the 'get_last_error' handler and other tools.

  function parseLogFile() {
    if (!existsSync(LOG_FILE)) {
      return [];
    }
  
    const content = readFileSync(LOG_FILE, 'utf8');
    const entries = [];
    const blocks = content.split('---CMD---').filter(block => block.trim());
  
    for (const block of blocks) {
      const entry = {
        command: '',
        output: '',
        exitCode: null,
        timestamp: null,
      };
  
      // Extract command (line starting with $)
      const cmdMatch = block.match(/^\s*\$\s*(.+?)(?:\n|---)/m);
      if (cmdMatch) {
        entry.command = cmdMatch[1].trim();
      }
  
      // Extract output
      const outputMatch = block.match(/---OUTPUT---\n([\s\S]*?)(?:---EXIT|---END|$)/);
      if (outputMatch) {
        entry.output = outputMatch[1].trim();
      }
  
      // Extract exit code
      const exitMatch = block.match(/---EXIT:(\d+)---/);
      if (exitMatch) {
        entry.exitCode = parseInt(exitMatch[1], 10);
      }
  
      // Extract timestamp if present
      const timestampMatch = block.match(/---TIMESTAMP:(.+?)---/);
      if (timestampMatch) {
        entry.timestamp = timestampMatch[1];
      }
  
      if (entry.command) {
        entries.push(entry);
      }
    }
  
    return entries;
  }