Migrate To Openchoreo

Migrate to OpenChoreo

Take an application spec (Helm chart, Kustomize overlay, Docker Compose file, or raw Kubernetes YAML) and produce a step-by-step migration plan. The plan is the deliverable; the agent iterates with the user as decisions and feedback land.

Step 0 — Tooling

node --version (≥ 18) is always required (the preview server is Node). For each source format, a renderer that turns the input into something analyzable:

• Helm → helm (≥ 3.12) to helm template the chart
• Kustomize → kustomize (or kubectl kustomize) to build the overlay
• Docker Compose → nothing extra (the compose file is YAML, read it directly)
• Raw YAML → nothing extra

A missing renderer isn't a hard stop — install if possible (rendering is the clean path; values + conditionals + ranges decide what a chart actually emits, so only the rendered output is faithful). If install isn't feasible, do a best-effort enumeration from the raw templates and flag that the analysis is degraded, not exhaustive — the plan still ships, just with the limitation called out. Compose and raw YAML need nothing extra.

Step 1 — Load the model primer (MANDATORY read)

Read ./references/concepts.md. The OpenChoreo workload model is intentionally narrow — what fits and what doesn't is the central question of this skill. Load once per session.

Step 2 — Get the manifests

Identify the source shape and render it to flat K8s YAML — that's what the rest of the analysis works against. If a piece of the input can't be rendered cleanly (a compose feature with no K8s equivalent, an operator-installed chart that needs a live cluster), render what you can and call the rest out as gaps.

Helm. Render with helm template <release> <chart> --namespace <ns> [--values <file>] --output-dir <run>/source-rendered (run helm dependency update <chart> first if Chart.yaml has unresolved deps); the render is values-conditional, so render each values file the user actually uses (dev / staging / prod). Then read the raw templates under <chart>/templates/ and <chart>/charts/*/templates/ to catch the conditional blocks ({{ if .Values.x }}, {{ range }}) that the current values didn't exercise — those are values-dependent shapes the plan should call out, not silently drop. Also grep for lookup (runtime cluster reads — output may be stale on a fresh cluster) and helm.sh/hook (no OpenChoreo analogue); flag affected files as gaps.

Kustomize: kustomize build <root> > <run>/source-rendered/all.yaml (or kubectl kustomize <root> > …). Most overlay patterns map to a concrete OpenChoreo construct — a Trait that patches, a per-env override on the binding, a Workload field — figure out which carries the intent and recommend that, instead of flagging. Only call it a gap when the overlay produces a shape the platform can't model at all.

Docker Compose: the compose file is already YAML — read it directly and map each service to a candidate workload (image/build, ports, environment, volumes, depends_on). Most compose features map to a concrete OpenChoreo construct — a CT field, a Trait that patches, a per-env override, a Workload field — figure out which carries the intent and recommend that, instead of flagging. Only call it a gap when the compose feature has no K8s analogue at all (host-level concerns, node-bound storage).

Raw YAML: copy <input>/ into <run>/source-rendered/. The file IS the manifest.

Each file may contain multiple YAML documents separated by --- — split by docs, not files. From here on, the analysis works on the rendered docs.

Step 3 — Inventory, then assess fit

Inventory first — read-only, classify every rendered doc by kind: workloads (Deployment / StatefulSet / CronJob / Job), discovery (Service / Ingress / HTTPRoute), config (ConfigMap / Secret), augmentations (HPA / PDB / ServiceMonitor / …), RBAC (ServiceAccount / Role / …), cluster-scoped & infra (CRD / webhook / operator / DaemonSet), foreign CRs. Every document lands in a bucket — an unclassified doc is a hole, and under-reading a big chart is the most common cause of a wrong plan. This one pass feeds both the fit verdict here and (for good-fit / partial-fit) the dependency ledger you'll build per ./references/build-the-plan.md.

Then assess fit — three buckets:

• good-fit — every resource in the source maps to an OpenChoreo primitive (Component, Workload, Resource, Trait, SecretReference). Predominantly workload-shaped (Deployments / StatefulSets / CronJobs / Jobs), no CRDs, no admission webhooks, no node-level DaemonSets, no cluster-scoped RBAC. Bundled stateful services that extract to a Resource still count as good-fit — extracting to a Resource is just a different primitive, not a loss. Proceed.
• partial-fit — workloads map cleanly, but some resource in the source genuinely cannot be brought into OpenChoreo and requires action outside the import: cluster-scoped RBAC, foreign CRs that depend on an external controller, an admission webhook the workloads need. Proceed and surface the out-of-scope pieces. (Needing a new ComponentType / ResourceType / Trait is not a partial-fit trigger — authoring is routine and surfaced as a create-this recommendation in the plan.)
• not-a-fit — dominantly infrastructure: operator install (CRDs + controller), CNI / network plugin, admission controller, APIService aggregator, DaemonSet-only. Stop. Don't pretend to model. Show the verdict + the signals; what the user does next with the source is out of scope.

Classification signals: CustomResourceDefinition → operator install (not-a-fit); MutatingWebhookConfiguration / ValidatingWebhookConfiguration → admission (not-a-fit); APIService → aggregator (not-a-fit); only DaemonSets → node agent / CNI (not-a-fit); ClusterRole / ClusterRoleBinding → partial-fit or not-a-fit; pure workloads → good-fit.

Before emitting the verdict, answer in chat: total rendered docs read, total classified, any unclassified (name them). An unclassified doc means the inventory isn't done — not a verdict you can ship.

Deliver the verdict + findings in chat — a short headline (good-fit / partial-fit / not-a-fit) and the signals behind it. No browser, no server for this step. For not-a-fit, that's the whole journey — stop there.

For good-fit / partial-fit, read ./references/build-the-plan.md before continuing — it carries the post-verdict playbook. Don't barrel from verdict straight into a finished plan on your own guesses.

What this skill does NOT do

• Touch the cluster. No kubectl, no MCP, no apply.
• Rebuild from source. BYOI by default — the image is whatever the user supplies at apply time; the skill doesn't evaluate registry access, image-pull credentials, or source licensing.
• Write the actual ComponentType / ResourceType / Trait YAML. The plan recommends what to author; the template is the user's to write.
• Pick deployment mode (auto-deploy vs GitOps vs manual apply), rollout strategy, or per-environment values — apply-time concerns the user owns.

Hard nos

These apply every turn, every step — not "during planning." Treat them as session-wide rules.

• Don't sample. Read every workload, config, parameterization file, and grouping. Render before classifying — static parsing misses values-conditional shapes.
• Delegate sweeps to sub-agents at scale. >5 groupings, >10 files this turn, or verdicting a large source → fan out one sub-agent per shard, each returns a summary, collapse back. Concurrent main-context Bash/Read still consumes your context — not sharding. (Claude Code: Agent tool; ToolSearch select:Agent if not loaded.)
• Never cd. Absolute paths in every Bash. cd mutates $PWD; the next preview.sh new "$PWD" then scaffolds .migrate-to-openchoreo/ wherever you last cd-ed (including inside the skill install).
• Don't author per-Component. A CT / RT / Trait captures a pattern; many Components instantiate one. Visibility, replicas, sizes, env values are parameters, not different types.
• Don't ask type internals. What a CT / RT / Trait renders is PE-side authoring. The plan recommends the pattern.
• Don't ask intent. Lift-and-shift vs re-model, applying vs exploring — none of it changes the plan. Forks ask about source ambiguity, never user goals.
• Don't thin the diagram. Every dependency renders. Split into more Projects to drill down, never drop edges for readability.
• Don't take silence as acceptance. If a fork wasn't answered, re-ask.
• Don't build the page before forks are answered. Forks are chat-only.
• Always recommend authoring CT / RT / Trait — never reference shipped. The skill can't know what ships (no install introspection). Bundled samples in references/sample-types/ are shape reference, not a menu. A foreign CR (apiVersion outside standard K8s + openchoreo.dev/* + gateway.networking.k8s.io/*) implies an external controller.
• Don't flag runtime concerns as blockers. Image-pull / registry access / licensing → apply-time. Calls into in-flight legacy peers → external with swap-when-onboarded; not a fit failure.
• Loud about gaps; conclusions, not disclaimers. Quietly unmapped resources mislead. Don't preface the plan with hedges — genuine forks go in the verdict-beat ask.
• Run the end-of-turn checklist before closing. See build-the-plan.md → End-of-turn checklist; a failed item = re-do. On the approval turn (the one that writes migration-plan.html), run it out loud — each item with pass / fail in chat, before the four-file write.