Create Pipeline

Generate Harness v0 Pipeline YAML and optionally push to Harness via MCP.

Instructions

1. Analyze codebase (if source code is available) - Scan the project to auto-detect language, build tools, test frameworks, containerization, deployment manifests, and target infrastructure. Use the detection tables and decision tree in references/codebase-analysis.md to determine:
   • Language and runtime version (package.json → Node.js, go.mod → Go, pom.xml → Java, etc.)
   • Build commands and base images
   • Test framework and report format (Jest → JUnit, pytest → JUnit XML, etc.)
   • Linter and formatter (ESLint, Prettier, Ruff, etc.)
   • Dockerfile presence and registry type (Docker Hub, ECR, GCR, ACR)
   • Deployment manifests → Harness service/deployment type (k8s manifests → Kubernetes, Chart.yaml → NativeHelm, task-definition.json → ECS, serverless.yml → ServerlessAwsLambda)
   • Existing CI/CD configs for migration (GitHub Actions, Jenkins, GitLab CI, etc.)
2. Clarify requirements - Confirm detected settings with the user. Ask about anything that couldn't be auto-detected — do not guess or use placeholders. If the user's request is ambiguous, ask before generating YAML. Examples of what to ask when missing:
   • Deployment target / infrastructure: region (e.g. us-east-1), cluster name or ID, account ID (e.g. AWS account for ECR/ECS)
   • Registry: which registry (Docker Hub, ECR, GCR, ACR), registry identifier/URL, repo path
   • Cloud provider: which account, region, and resource identifiers for connectors/infrastructure
   • Approval gates, notification channels if relevant Critical rule: Never hardcode placeholder values (e.g. 123456789012, us-east-1, my-cluster) for deployment target, region, registry, or cluster when the user did not specify them — ask the user instead. If the user did not specify region, account ID, cluster, or registry (e.g. "deploys to ECS" with no region or cluster), ask the user for those values before generating YAML.
3. Select native steps - Always prefer Harness native steps over Run or ShellScript steps. Consult references/native-steps.md for the full mapping. Key rules:
   • Docker build/push → use BuildAndPushDockerRegistry / BuildAndPushECR / BuildAndPushGCR / BuildAndPushACR (never Run: docker build && docker push)
   • K8s deploy → use K8sRollingDeploy / K8sBlueGreenDeploy / K8sCanaryDeploy (never Run: kubectl apply)
   • Helm deploy → use HelmDeploy (never Run: helm upgrade --install)
   • ECS deploy → use EcsRollingDeploy (never Run: aws ecs update-service)
   • Terraform → use TerraformPlan / TerraformApply (never Run: terraform apply)
   • Security scanning → use native STO steps (AquaTrivy, Snyk, Sonarqube, Semgrep, etc.)
   • Uploads → use S3Upload / GCSUpload (never Run: aws s3 cp)
   • Approvals → use HarnessApproval / JiraApproval (never polling scripts)
   • Ticketing → use JiraCreate / ServiceNowCreate (never Run: curl)
   • Use Run steps only for custom build/test/lint commands with no native equivalent
   • Test steps: Any Run step that runs unit or integration tests must include a reports block (e.g. type: JUnit, spec.paths) so Harness can capture results; see references/codebase-analysis.md for framework → report path.
4. Generate valid YAML following the structure below, using the detected build/test/deploy commands. Validation rules: (a) Stage names must match ^[a-zA-Z_0-9-.][-0-9a-zA-Z_\\s.]{0,127}$ — use only letters, numbers, spaces, hyphens, underscores, or periods (no commas). (b) Every CI and CD stage must include a failureStrategies array (Approval stages do not require one). For CI use MarkAsFailure (never Ignore — it hides failures); for CD use StageRollback.
5. Optionally create via MCP — First verify the project exists (see "Creating via MCP" section below), then use harness_create with resource_type pipeline and body: { yamlPipeline: "<YAML string>" }

Pipeline Structure

pipeline:
  identifier: my_pipeline       # ^[a-zA-Z_][0-9a-zA-Z_]{0,127}$
  name: My Pipeline
  orgIdentifier: default
  projectIdentifier: my_project
  tags: {}
  properties:
    ci:
      codebase:                  # Required for CI stages
        connectorRef: github_connector
        repoName: my-repo
        build:
          type: branch
          spec:
            branch: <+trigger.branch>
  stages:
    - stage: ...

Stage Types

CI Stage (type: CI)

- stage:
    identifier: build
    name: Build
    type: CI
    spec:
      cloneCodebase: true
      platform:
        os: Linux
        arch: Amd64
      runtime:
        type: Cloud    # Cloud, Kubernetes, VM, Docker
        spec: {}
      execution:
        steps:
          - step: ...
    failureStrategies:
      - onFailure:
          errors: [AllErrors]
          action:
            type: MarkAsFailure

CD Stage (type: Deployment)

- stage:
    identifier: deploy
    name: Deploy
    type: Deployment
    spec:
      deploymentType: Kubernetes  # Kubernetes, NativeHelm, ECS, ServerlessAwsLambda, Ssh, WinRm, AzureWebApp
      service:
        serviceRef: my_service
      environment:
        environmentRef: dev
        infrastructureDefinitions:
          - identifier: k8s_dev
      execution:
        steps:
          - step: ...
        rollbackSteps:
          - step: ...
    failureStrategies:
      - onFailure:
          errors: [AllErrors]
          action:
            type: StageRollback

Approval Stage (type: Approval)

HarnessApproval requires approvers.disallowPipelineExecutor (required by the API). Set it to true so the pipeline executor cannot approve their own run; omit it and the API returns "disallowPipelineExecutor: is missing but it is required".

- stage:
    identifier: approval
    name: Approval
    type: Approval
    spec:
      execution:
        steps:
          - step:
              identifier: approve
              name: Approve
              type: HarnessApproval
              spec:
                approvalMessage: "Please review and approve"
                approvers:
                  userGroups: [prod_approvers]
                  minimumCount: 1
                  disallowPipelineExecutor: true
                includePipelineExecutionHistory: true
              timeout: 1d
    failureStrategies:
      - onFailure:
          errors: [AllErrors]
          action:
            type: Abort

Common Step Types

Run Step

- step:
    identifier: run_tests
    name: Run Tests
    type: Run
    spec:
      shell: Bash          # Sh, Bash, Powershell, Pwsh, Python
      command: |
        npm ci
        npm test
      envVariables:
        NODE_ENV: test
      reports:
        type: JUnit
        spec:
          paths: ["junit.xml"]

Build and Push Docker

- step:
    identifier: docker_push
    name: Build and Push
    type: BuildAndPushDockerRegistry
    spec:
      connectorRef: dockerhub
      repo: myorg/myimage
      tags: [latest, <+pipeline.sequenceId>]
      dockerfile: Dockerfile

K8s Rolling Deploy

- step:
    identifier: rollout
    name: Rollout
    type: K8sRollingDeploy
    spec:
      skipDryRun: false
    timeout: 10m

K8s Rolling Rollback

- step:
    identifier: rollback
    name: Rollback
    type: K8sRollingRollback
    spec: {}
    timeout: 10m

For the complete catalog of 300+ native step types (cloud deployments, security scanners, IaC, ticketing, approvals, GitOps, and more), consult references/native-steps.md. Always check this reference before using a Run step.

Variables and Expressions

pipeline:
  variables:
    - name: env
      type: String
      default: dev
    - name: api_key
      type: Secret
      value: <+secrets.getValue("api_key")>

Common expressions:

• <+pipeline.variables.env> - Pipeline variable
• <+stage.variables.VAR> - Stage variable
• <+steps.step_id.output.outputVariables.VAR> - Step output
• <+trigger.branch>, <+trigger.commitSha> - Trigger info
• <+secrets.getValue("name")> - Secret reference
• <+pipeline.sequenceId> - Build number

Parallel Execution

# Parallel steps
- parallel:
    - step: ...
    - step: ...

# Parallel stages
stages:
  - parallel:
      - stage: ...
      - stage: ...

Failure Strategies

failureStrategies:
  - onFailure:
      errors: [AllErrors]     # AllErrors, Timeout, Authentication, Connectivity
      action:
        type: StageRollback   # Ignore, Retry, MarkAsSuccess, Abort, StageRollback, PipelineRollback

Conditional Execution

- stage:
    when:
      pipelineStatus: Success
      condition: <+pipeline.variables.deploy> == "true"

Matrix Strategy

Placement: strategy must be at the stage level, as a sibling of spec, not inside spec. If you put strategy under spec, the matrix will not be applied and the UI will not show matrix iterations.

Reference matrix values in steps with <+stage.matrix.TAG> (e.g. <+stage.matrix.python_version>). Use hyphen-free dimension names (e.g. python_version not python-version).

- stage:
    identifier: test_matrix
    name: Test Matrix
    type: CI
    spec:
      cloneCodebase: true
      platform:
        os: Linux
        arch: Amd64
      runtime:
        type: Cloud
        spec: {}
      execution:
        steps:
          - step:
              type: Run
              spec:
                image: node:<+stage.matrix.node_version>
                command: npm test
    strategy:
      matrix:
        node_version: ["16", "18", "20"]
        os: [linux, macos]
      maxConcurrency: 3
    failureStrategies:
      - onFailure:
          errors: [AllErrors]
          action:
            type: Abort

Creating via MCP

After generating the YAML, create it in Harness:

1. Verify the project exists — List projects with harness_list (resource_type: project, org_id) to confirm. If the project does not exist, create it first with harness_create (resource_type: project, body: { identifier, name }) or ask the user.
2. Create the pipeline — Use harness_create with the pipeline YAML serialized as a yamlPipeline string in the body. Do not pass a nested JSON pipeline object; it causes serialization errors.

Call MCP tool: harness_create
Parameters:
  resource_type: "pipeline"
  org_id: "<organization>"
  project_id: "<project>"
  body: { yamlPipeline: "<full pipeline YAML string, including 'pipeline:' root key>" }

Example body (abbreviated):

{
  "yamlPipeline": "pipeline:\n  identifier: nodejs_ci\n  name: Node.js CI\n  projectIdentifier: my_project\n  orgIdentifier: default\n  stages:\n    - stage:\n        identifier: build\n        ..."
}

To update an existing pipeline, use the same yamlPipeline format:

Call MCP tool: harness_update
Parameters:
  resource_type: "pipeline"
  resource_id: "<pipeline_identifier>"
  org_id: "<organization>"
  project_id: "<project>"
  body: { yamlPipeline: "<full updated pipeline YAML string>" }

To verify it was created:

Call MCP tool: harness_get
Parameters:
  resource_type: "pipeline"
  resource_id: "<pipeline_identifier>"
  org_id: "<organization>"
  project_id: "<project>"

Complete CI Example

pipeline:
  identifier: nodejs_ci
  name: Node.js CI
  projectIdentifier: my_project
  orgIdentifier: default
  properties:
    ci:
      codebase:
        connectorRef: github_connector
        repoName: my-app
        build:
          type: branch
          spec:
            branch: <+trigger.branch>
  stages:
    - stage:
        identifier: build_and_test
        name: Build and Test
        type: CI
        spec:
          cloneCodebase: true
          platform:
            os: Linux
            arch: Amd64
          runtime:
            type: Cloud
            spec: {}
          execution:
            steps:
              - step:
                  identifier: install
                  name: Install
                  type: Run
                  spec:
                    shell: Bash
                    command: npm ci
              - parallel:
                  - step:
                      identifier: lint
                      name: Lint
                      type: Run
                      spec:
                        shell: Bash
                        command: npm run lint
                  - step:
                      identifier: test
                      name: Test
                      type: Run
                      spec:
                        shell: Bash
                        command: npm test
                        reports:
                          type: JUnit
                          spec:
                            paths: ["junit.xml"]
              - step:
                  identifier: docker_push
                  name: Build and Push
                  type: BuildAndPushDockerRegistry
                  spec:
                    connectorRef: dockerhub
                    repo: myorg/my-app
                    tags: [<+pipeline.sequenceId>, latest]
        failureStrategies:
          - onFailure:
              errors: [AllErrors]
              action:
                type: MarkAsFailure

Complete CD Example

pipeline:
  identifier: k8s_deploy
  name: K8s Deploy
  projectIdentifier: my_project
  orgIdentifier: default
  stages:
    - stage:
        identifier: deploy_staging
        name: Deploy Staging
        type: Deployment
        spec:
          deploymentType: Kubernetes
          service:
            serviceRef: my_service
          environment:
            environmentRef: staging
            infrastructureDefinitions:
              - identifier: k8s_staging
          execution:
            steps:
              - step:
                  identifier: rollout
                  name: Rollout
                  type: K8sRollingDeploy
                  spec:
                    skipDryRun: false
                  timeout: 10m
            rollbackSteps:
              - step:
                  identifier: rollback
                  name: Rollback
                  type: K8sRollingRollback
                  spec: {}
                  timeout: 10m
        failureStrategies:
          - onFailure:
              errors: [AllErrors]
              action:
                type: StageRollback
    - stage:
        identifier: approval
        name: Production Approval
        type: Approval
        spec:
          execution:
            steps:
              - step:
                  identifier: approve
                  name: Approve Prod
                  type: HarnessApproval
                  spec:
                    approvalMessage: "Approve production deployment?"
                    approvers:
                      userGroups: [prod_approvers]
                      minimumCount: 1
                      disallowPipelineExecutor: true
                    includePipelineExecutionHistory: true
                  timeout: 1d
        failureStrategies:
          - onFailure:
              errors: [AllErrors]
              action:
                type: Abort
    - stage:
        identifier: deploy_prod
        name: Deploy Production
        type: Deployment
        spec:
          deploymentType: Kubernetes
          service:
            serviceRef: my_service
          environment:
            environmentRef: prod
            infrastructureDefinitions:
              - identifier: k8s_prod
          execution:
            steps:
              - step:
                  identifier: rollout
                  name: Rollout
                  type: K8sRollingDeploy
                  spec:
                    skipDryRun: false
                  timeout: 10m
            rollbackSteps:
              - step:
                  identifier: rollback
                  name: Rollback
                  type: K8sRollingRollback
                  spec: {}
                  timeout: 10m
        failureStrategies:
          - onFailure:
              errors: [AllErrors]
              action:
                type: StageRollback

Examples

Create a CI pipeline

/create-pipeline
Create a CI pipeline for a Node.js app that builds, runs tests, and pushes to Docker Hub

Create a CD pipeline with approvals

/create-pipeline
Create a Kubernetes deployment pipeline with staging, manual approval, and production stages

Create a combined CI/CD pipeline

/create-pipeline
Build a pipeline that runs tests, pushes a Docker image, and deploys to ECS with rollback

Create a matrix build pipeline

/create-pipeline
Create a CI pipeline that tests across Node 16, 18, and 20 on both Linux and macOS

Create a pipeline with parallel stages

/create-pipeline
Create a pipeline with parallel test stages for unit tests, integration tests, and linting

Performance Notes

• Always check references/native-steps.md before using a Run step. Native steps provide better error handling and UI integration.
• Verify the target project exists (harness_list, resource_type: project) before creating the pipeline.
• Validate that all referenced connectors, services, and environments exist before creating the pipeline.
• For CD pipelines, confirm the deployment type matches the service definition type.
• Quality of generated YAML is more important than speed. Verify structure before submitting.

Troubleshooting

YAML Validation Errors

• Pipeline/step identifier: must match ^[a-zA-Z_][0-9a-zA-Z_]{0,127}$ (letters, numbers, underscores only).
• Stage name: must match ^[a-zA-Z_0-9-.][-0-9a-zA-Z_\\s.]{0,127}$ — no commas; use letters, numbers, spaces, hyphens, underscores, or periods (e.g. use "Build Test and Push" not "Build, Test and Push").
• Every CI and CD stage must include a failureStrategies array (Approval stages do not require one); omit it and the API returns "failureStrategies: is missing but it is required". For CI use type: MarkAsFailure; for CD use type: StageRollback.
• Stage type is case-sensitive: CI, Deployment, Approval, Custom
• Every stage must have a spec field
• Matrix not applied / not visible in UI: strategy must be a sibling of spec on the stage, not inside spec. Use strategy.matrix at the stage level and reference values as <+stage.matrix.TAG>.
• HarnessApproval: "disallowPipelineExecutor: is missing but it is required" — add approvers.disallowPipelineExecutor: true to the step spec.

MCP Creation Errors

• Project not found — Verify the project exists with harness_list (resource_type: project, org_id). Create it first with harness_create (resource_type: project, body: { identifier, name }) or confirm org_id/project_id are correct.
• Missing required fields for pipeline: pipeline — Pass the body as { yamlPipeline: "<full pipeline YAML string>" } instead of a nested JSON pipeline object. Nested JSON causes serialization errors.
• DUPLICATE_IDENTIFIER — Pipeline already exists; use harness_update instead
• CONNECTOR_NOT_FOUND — Create the connector first or fix connectorRef
• ACCESS_DENIED — Check API key permissions

Ambiguous or Incomplete Requests

• "Deploys to ECS" / "K8s deploy" / "push to registry" with no specifics — Ask the user for region, account ID, cluster name/ID, and which registry (ECR, Docker Hub, etc.) before generating YAML. Do not insert placeholder values (e.g. us-east-1, 123456789012).

Execution Failures

• Missing <+input> values - provide via input sets or runtime inputs
• Connector auth expired - test with harness_execute (resource_type: "connector", action: "test_connection")
• Delegate offline - check with harness_status