For the complete documentation index, see llms.txt. Markdown versions of all docs pages are available by appending .md to any docs URL.

Configure a Harness, the resource that defines which runtime executes an agent and what infrastructure it runs on.

Review configuration guidelines and reference for the Harness resource: every field it takes, the four runtimes it can select, and what each runtime supports. To understand a Harness and why it is separate from an AgentTemplate, see the core concepts.

Configure a Harness

The following configuration is for a complete Harness resource. Only workload, substrate, and one runtime block are required.

kubectl apply -f - <<EOF
apiVersion: kagent.dev/v1alpha3
kind: Harness
metadata:
  name: my-harness
  namespace: kagent
spec:
  # Exactly one runtime block: kagent, codex, claude, or byo.
  kagent: {}
  workload:
    image: ghcr.io/kagent-dev/kagent/golang-adk@sha256:c8ab012e9774d50e20ffa8cd035ddebff69486a2843b3af281f5f6ebc67ab512
  env:
    - name: LOG_LEVEL
      value: info
    - name: MY_API_KEY
      credentialRef:
        name: my-secret
        key: api-key
  substrate:
    workerPoolRef:
      name: kagent-default
    snapshotPolicy:
      location: gs://<your-bucket>/kagent/
  allowedAgentTemplates:
    selector:
      matchLabels:
        kagent.dev/harness: my-harness
EOF

Review the following table to understand this configuration. For more information, see the API reference.

Choose a runtime

A Harness names exactly one of the following four runtimes, and that choice decides what executes an agent and how much of kagent’s feature set the agent can use.

The kagent and byo runtimes compile through the same path, so they accept the same model providers and the same AgentTemplate features. The codex and claude runtimes are purpose-built adapters, and each accepts a narrower slice.

Runtime-specific settings

spec.kagent is the only runtime block that takes settings of its own. The rest are empty.

spec:
  kagent:
    memory:
      modelConfigRef:
        name: embedding-model-config
      ttlDays: 30

Setting memory gives every agent on this Harness memory that persists across conversations. For how agents store and retrieve it, see Agent memory.

Model provider support

The runtime that a Harness selects decides which ModelConfig its AgentTemplates can use.

Some supported combinations still carry restrictions.

Tool and skill support

The coding-agent runtimes also constrain what an AgentTemplate can ask for.

The kagent and byo runtimes take the full set. For more information about what an AgentTemplate can bind, see About tools.

Telemetry content settings

Tracing and audit logging both carry the prompts and replies that an agent exchanges with a model. Two settings in the kagent Helm chart decide whether that content leaves the runtime, and each one reaches a different set of runtimes. Both default to false, and both take effect only where tracing or audit logging is already enabled.

otel:
  captureSensitiveContent: false
  logging:
    captureRawApiBodies: false

The kagent runtime honors neither setting. To include message content for an agent on that runtime, set OTEL_INSTRUMENTATION_GENAI_CAPTURE_MESSAGE_CONTENT in the Harness spec.env field. That variable defaults differently for each signal, so check the audit prompt onfiguration before you set it.

The controller sends the byo runtime no telemetry configuration, so neither setting reaches it. A byo image that implements OpenTelemetry itself reads whatever the Harness spec.env field holds. For more information, see Tracing.

Check that a Harness is ready

The READY column reports whether a Harness’s dependencies resolved.

kubectl get harness -n kagent

A Harness that is not Ready most often names a WorkerPool that does not exist yet. For the specific reason, read its conditions with kubectl describe harness <harness-name> -n kagent.

Ready covers the Harness’s own dependencies, not whether a given agent runs on it. Whether an AgentTemplate compiles against this Harness is reported on the AgentTemplate, under status.harnesses. For that check and the conditions it reports, see Your first agent.

Next steps