create-policy

name	create-policy
description	Create OPA governance policies for Harness via MCP. Define policies that enforce compliance rules on pipelines, services, environments, feature flags, artifacts, code repositories, templates, SBOM, security tests, Terraform, GitOps, connectors, secrets, and more. Use when asked to create, write, fix, or explain an OPA policy, Rego rule, deny rule, governance policy, compliance rule, or policy-as-code for any Harness entity. Trigger phrases: create policy, OPA policy, governance policy, compliance rule, rego policy, deny rule, enforce policy, security policy, supply chain governance.
metadata	{"author":"Harness","version":"1.0.0","mcp-server":"harness-mcp-v2"}
license	Apache-2.0
compatibility	Requires Harness MCP v2 server (harness-mcp-v2)

Create Policy

Create OPA governance policies for Harness Software Supply Chain Assurance (SCS) via MCP.

Instructions

Step 1: Identify Policy Requirements

Determine what the policy should enforce:

• What entity type is the policy targeting? (pipeline, service, environment, feature flag, etc.)
• What is the enforcement action (warn, deny)?
• What scope should the policy apply to?
• What action triggers the policy? (onrun, onsave, onstep, etc.)

For writing Rego policies, consult references/rego-writing-guide.md for the complete Rego writing rules, entity types, package names, and common patterns. For entity-specific schemas and examples, see the entity reference files listed in that guide.

Step 2: Create the Policy

Call MCP tool: harness_create
Parameters:
  resource_type: "scs_opa_policy"
  org_id: "<organization>"
  project_id: "<project>"
  body: <policy definition>

Step 3: Verify Compliance Results

After a policy is created, check compliance status on artifacts or repositories:

Call MCP tool: harness_list
Parameters:
  resource_type: "scs_compliance_result"
  org_id: "<organization>"
  project_id: "<project>"

Common Policy Patterns

Require SBOM Generation

Enforce that all artifacts have an SBOM before deployment:

package harness.artifact

deny[msg] {
  not input.artifact.sbom
  msg := "Artifact must have an SBOM before deployment"
}

Block Critical Vulnerabilities

Deny deployment of artifacts with critical CVEs:

package harness.artifact

deny[msg] {
  vuln := input.artifact.vulnerabilities[_]
  vuln.severity == "CRITICAL"
  msg := sprintf("Critical vulnerability %s found in artifact", [vuln.cve_id])
}

Enforce Approved Base Images

Restrict container images to approved base images:

package harness.artifact

approved_bases := {"alpine", "distroless", "ubuntu"}

deny[msg] {
  not approved_bases[input.artifact.base_image]
  msg := sprintf("Base image '%s' is not in the approved list", [input.artifact.base_image])
}

Require Signed Artifacts

Enforce artifact signing before deployment:

package harness.artifact

deny[msg] {
  not input.artifact.signed
  msg := "Artifact must be signed before deployment"
}

Related Resource Types

Resource Type	Operations	Description
scs_opa_policy	create	Create governance policies
scs_compliance_result	list	Check policy compliance status
artifact_security	list, get	View artifact security posture
code_repo_security	list, get	View repository security posture
scs_chain_of_custody	get	Verify artifact provenance

Rego Policy Reference Files

For writing Rego policies for any Harness entity, consult these reference files:

• Rego writing guide and rules — Entity types, package names, Rego patterns, quality checklist
• Pipeline policies and schema — Pipeline input schema, step/stage nesting, walk patterns
• Feature Flag / FME policies — Feature flag, definition, FME environment, segment schemas
• Service, Environment, Infrastructure — Service, env, infra schemas and examples
• Security Tests policies — Security test output schema, severity/coverage checks
• SBOM policies — SBOM deny/allow list patterns with semver comparison
• Terraform and Workspace — Terraform plan, cost, state, workspace schemas
• GitOps Application — GitOps app schema, namespace/label/revision policies
• Code Repository — Code repo naming, visibility, branch policies
• Variable policies — Variable schema, role-based restrictions
• Override policies — Override schema, config file and variable protection
• Connector policies — Connector schema, type/auth/naming restrictions
• Secret policies — Secret schema, naming/type/provider restrictions
• Template policies — Template schema, approval/versioning/environment checks
• Database DevOps policies — SQL statement governance, DDL restrictions, transaction limits
• Upstream Firewall — Firewall package schema, CVE/license policies
• Advanced patterns — Exception handling, walk, scoped references, exemptions

Examples

• "Create a policy to block critical CVEs" -- Create OPA deny rule for critical severity
• "Enforce SBOM generation for all artifacts" -- Create policy requiring SBOM presence
• "Only allow approved base images" -- Create policy with allowed base image list
• "Require artifact signing before production" -- Create policy checking signature status
• "Require approval before production deployments" -- Pipeline policy with Approval stage check
• "Enforce disallowPipelineExecutor on approval steps" -- Pipeline walk-based step check
• "Block Terraform plans exceeding $100/month" -- Terraform plan cost policy
• "Require feature flag descriptions" -- FME feature flag onsave policy
• "Prevent GitOps deployments to kube-system" -- GitOps namespace restriction
• "Check which artifacts violate our policies" -- List scs_compliance_result

Performance Notes

• Validate Rego syntax before submitting. Common issues: missing package declaration, deny rules without msg return.
• Ensure the policy package name follows package harness.<domain> convention.
• Test policy logic mentally against expected inputs before creating.

Troubleshooting

Policy Not Enforcing

• Policies are create-only via MCP -- verify the policy was created successfully
• Check that the policy scope matches the target artifacts/repositories
• Use scs_compliance_result to verify the policy is being evaluated

Policy Syntax Errors

• OPA policies use Rego language -- validate syntax before submitting
• Package names should follow package harness.<domain> convention
• Deny rules must return a msg string explaining the violation

Limitations

• MCP supports create-only for OPA policies (no list, update, or delete via MCP)
• For managing existing policies, use the Harness UI under Supply Chain Assurance settings
• Policies apply within the project scope where they are created