docker_logs

Instructions

Implementation Reference

• src/tools/docker.ts:216-226 (handler)

  Main handler function that constructs and executes the 'docker logs' command using flags from input args and the executeDockerCommand helper.

  export async function dockerLogs(args: z.infer<typeof dockerLogsSchema>): Promise<ToolResponse> {
    const tailFlag = args.tail ? `--tail ${args.tail}` : '';
    const followFlag = args.follow ? '-f' : '';
    const sinceFlag = args.since ? `--since ${args.since}` : '';
    const timestampsFlag = args.timestamps ? '-t' : '';
  
    return executeDockerCommand(
      `docker logs ${tailFlag} ${followFlag} ${sinceFlag} ${timestampsFlag} ${args.container}`.trim(),
      args.cwd
    );
  }

• src/tools/docker.ts:96-103 (schema)

  Zod schema defining the input parameters and validation for the docker_logs tool.

  export const dockerLogsSchema = z.object({
    container: z.string().describe('Container name or ID'),
    tail: z.number().optional().describe('Number of lines to show from the end of logs'),
    follow: z.boolean().optional().default(false).describe('Follow log output (not recommended for MCP)'),
    since: z.string().optional().describe('Show logs since timestamp (e.g., "2023-01-01T00:00:00")'),
    timestamps: z.boolean().optional().default(false).describe('Show timestamps'),
    cwd: z.string().optional().describe('Working directory')
  });

• src/tools/docker.ts:378-393 (registration)

  Tool registration object in the dockerTools array, which is exported and included in the server's tool list response.

  {
    name: 'docker_logs',
    description: 'Fetch logs from a container',
    inputSchema: {
      type: 'object',
      properties: {
        container: { type: 'string', description: 'Container name or ID' },
        tail: { type: 'number', description: 'Number of lines to show from the end of logs' },
        follow: { type: 'boolean', default: false, description: 'Follow log output (not recommended for MCP)' },
        since: { type: 'string', description: 'Show logs since timestamp (e.g., "2023-01-01T00:00:00")' },
        timestamps: { type: 'boolean', default: false, description: 'Show timestamps' },
        cwd: { type: 'string', description: 'Working directory' }
      },
      required: ['container']
    }
  },

• src/index.ts:447-449 (registration)

  Dispatch logic in the main MCP server request handler that routes 'docker_logs' calls to the handler function after schema validation.

  if (name === 'docker_logs') {
    const validated = dockerLogsSchema.parse(args);
    return await dockerLogs(validated);

• src/tools/docker.ts:21-62 (helper)

  Helper function that executes Docker shell commands via child_process.exec and formats the ToolResponse.

  async function executeDockerCommand(command: string, cwd?: string): Promise<ToolResponse> {
    try {
      const { stdout, stderr } = await execAsync(command, {
        cwd: cwd || process.cwd(),
        shell: '/bin/bash',
        maxBuffer: 10 * 1024 * 1024, // 10MB buffer for logs
        timeout: 60000 // 60 second timeout for builds
      });
  
      return {
        content: [
          {
            type: "text" as const,
            text: JSON.stringify({
              success: true,
              command: command,
              stdout: stdout.trim(),
              stderr: stderr.trim(),
              cwd: cwd || process.cwd()
            }, null, 2)
          }
        ]
      };
    } catch (error: any) {
      return {
        content: [
          {
            type: "text" as const,
            text: JSON.stringify({
              success: false,
              command: command,
              stdout: error.stdout?.trim() || '',
              stderr: error.stderr?.trim() || error.message,
              exitCode: error.code || 1,
              cwd: cwd || process.cwd()
            }, null, 2)
          }
        ],
        isError: true
      };
    }
  }