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AGENTS.md

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+# AGENTS.md - watcher-operator
+
+## Project overview
+
+watcher-operator is a Kubernetes operator that manages
+[OpenStack Watcher](https://docs.openstack.org/watcher/latest/)
+on OpenShift/Kubernetes. It is part of the
+[openstack-k8s-operators](https://github.com/openstack-k8s-operators) project.
+
+## Tech stack
+
+| Layer | Technology |
+|-------|------------|
+| Language | Go (modules, multi-module workspace via `go.work`) |
+| Scaffolding | [Kubebuilder v4](https://book.kubebuilder.io/) + [Operator SDK](https://sdk.operatorframework.io/) |
+| CRD generation | controller-gen (DeepCopy, CRDs, RBAC, webhooks) |
+| Config management | Kustomize |
+| Packaging | OLM bundle |
+| Testing | Ginkgo/Gomega + envtest (functional), KUTTL (integration) |
+| Linting | golangci-lint (`.golangci.yaml`) |
+| CI | Zuul (`zuul.d/`), Prow (`.ci-operator.yaml`), GitHub Actions |
+
+## Directory structure
+
+**Maintenance rule:** when directories are added, removed, or renamed, or when their purpose changes, update this table to match.
+
+| Directory | Contents |
+|-----------|----------|
+| `api/v1beta1/` | CRD types (`watcher.openstack.org/v1beta1`), conditions, webhook markers |
+| `internal/controller/` | Reconcilers for Watcher, WatcherAPI, WatcherApplier, WatcherDecisionEngine |
+| `internal/watcher/` | Watcher resource-building helpers |
+| `internal/watcherapi/` | WatcherAPI resource-building helpers |
+| `internal/watcherapplier/` | WatcherApplier resource-building helpers |
+| `internal/watcherdecisionengine/` | WatcherDecisionEngine resource-building helpers |
+| `internal/webhook/` | Webhook implementations |
+| `templates/` | Config templates per service, mounted via `OPERATOR_TEMPLATES` |
+| `test/functional/` | envtest-based Ginkgo/Gomega tests |
+| `test/kuttl/` | KUTTL integration tests |
+
+## Build commands
+
+After modifying Go code, always run: `make generate manifests fmt vet`.
+
+## Code style guidelines
+
+- Follow standard openstack-k8s-operators conventions and lib-common patterns.
+- Use `lib-common` modules for conditions, endpoints, TLS, storage, and other
+  cross-cutting concerns rather than re-implementing them.
+- CRD types live in `api/v1beta1/`.
+- Controller logic goes in `internal/controller/`.
+  Resource-building helpers go in `internal/<service>/` packages.
+- Config templates are split per service under `templates/` and mounted at
+  runtime via the `OPERATOR_TEMPLATES` environment variable.
+- Webhook logic is split between the kubebuilder markers in `api/` and
+  the implementation in `internal/webhook/`.
+
+## Testing
+
+- Functional tests use the envtest framework with Ginkgo/Gomega and live in
+  `test/functional/`.
+- KUTTL integration tests live in `test/kuttl/`.
+- Run all functional tests: `make test`.
+- When adding a new field or feature, add corresponding test cases in
+  `test/functional/` and update fixture data accordingly.
+
+## Key dependencies
+
+- [lib-common](https://github.com/openstack-k8s-operators/lib-common): shared modules for conditions, endpoints, database, TLS, secrets, etc.
+- [infra-operator](https://github.com/openstack-k8s-operators/infra-operator): RabbitMQ and topology APIs.
+- [mariadb-operator](https://github.com/openstack-k8s-operators/mariadb-operator): database provisioning.
+- [keystone-operator](https://github.com/openstack-k8s-operators/keystone-operator): identity service registration.
+- [dev-docs](https://github.com/openstack-k8s-operators/dev-docs): shared development guide covering operator conventions, debugging, testing, and best practices.
+- [Documentation](docs/main.adoc): install guide and user workflows.