Kubernetes Ecosystem Schema Catalog

A hosted catalog of JSON Schemas and LLM-optimized indexes for Kubernetes and the CNCF Ecosystem,
generated with flux-schema and refreshed daily from
upstream stable releases.

Using the catalog for validation

The catalog is served from Cloudflare's global network at
schemas.fluxoperator.dev, where you can
also search and browse every project and their schemas.

flux schema validate ./manifests -s ecosystem

The ecosystem schema location expands to
https://schemas.fluxoperator.dev/catalog.

The catalog also keeps versioned snapshots for the six most recent minor
releases of Kubernetes, OpenShift and Flux, so validation can be pinned to
the minors your clusters run; see
Kubernetes versioning.

See the CLI guide for installation,
CI usage and configuration.

Explaining fields without a cluster

The explain command is like kubectl explain without a cluster at
hand (AI agents get the same capability through the MCP server below):

flux schema explain -s ecosystem hr.spec.dependsOn

GROUP:      helm.toolkit.fluxcd.io
KIND:       HelmRelease
VERSION:    v2

FIELD: dependsOn <[]Object>

DESCRIPTION:
    DependsOn may contain a DependencyReference slice with references to
    HelmRelease resources that must be ready before this HelmRelease can be
    reconciled.
...

Add --recursive to print nested fields, and --api-version to pick a
specific group/version when a kind is served by more than one.

MCP Server for AI agents

The catalog is exposed as a remote MCP server (streamable HTTP, no
authentication) at https://schemas.fluxoperator.dev/mcp. It gives AI agents
an offline replacement for kubectl explain, backed by the .fields.txt
field indexes
that ship alongside every schema.

To use it, add the MCP config to your project's .mcp.json:

{
  "mcpServers": {
    "flux-schema-catalog": {
      "type": "http",
      "url": "https://schemas.fluxoperator.dev/mcp"
    }
  }
}

See the AI agents guide for the
available tools and per-client setup instructions.

Catalog

Each project's ID names its provenance manifest, which pins the upstream
commit and the digests of the generated files. The manifests are signed with
GitHub Artifact Attestations
and can be verified with the GitHub CLI:

curl -sO https://schemas.fluxoperator.dev/history/<ID>.json
gh attestation verify <ID>.json -R controlplaneio-fluxcd/schema-catalog

Platform

Provisioning

Runtime

Orchestration & Management

App Definition & Development

Observability & Analysis

Documentation

• Flux Schema CLI: the validator this catalog serves.
• Manifest validation guide: flags, schema resolution, CEL rules and config files.
• Custom catalog guide: extract and host your own schemas.