Answer
Point the source at a Helm repo (chart + targetRevision) or a Git path containing the chart, then supply overrides via helm.values (inline), helm.valueFiles, or helm.parameters. ArgoCD renders the chart with `helm template` (it doesn't use Tiller) and applies the resulting manifests, tracking them like any other resource.
source:
repoURL: https://github.com/org/charts
path: web
helm:
valueFiles: [values-prod.yaml]
parameters:
- name: image.tag
value: v1.4.2Real-world example Production overrides the image tag and replica count via a values-prod.yaml, while staging uses values-staging.yaml.