# pass a Jenkinsfile that does not contain an "agent" section ssh -p 8675 localhost declarative-linter < ./Jenkinsfile Errors encountered validating Jenkinsfile: WorkflowScript: 2: Not a valid section definition: "agent". Some extra configuration is required. @ line 2, column 3. agent ^ WorkflowScript: 1: Missing required section "agent" @ line 1, column 1. pipeline &#125; ^ pipeline {  agent any  stages { stage ('Initialize') { steps { echo 'Placeholder.' } }  } } ssh -p 8675 localhost declarative-linter < ./Jenkinsfile Jenkinsfile successfully validated. 77 In this second example, the  Jenkinsfile  has been updated to include the missing  any  on  agent . The linter now reports that the Pipeline is valid. Linter output for invalid Jenkinsfile Jenkinsfile Linter output for valid Jenkinsfile