rancher-mcp-server

Model Context Protocol (MCP) server for the Rancher ecosystem: multi-cluster Kubernetes, Harvester HCI (VMs, storage, networks), and Fleet GitOps.

Demo

A walkthrough of how this MCP server works (example in Cursor).

https://github.com/user-attachments/assets/7d8fb814-e504-47b4-956d-28f43aeea3b8

Features

• Harvester toolset: List/get VMs, images, volumes, networks, hosts; VM actions; addon list/switch (enable/disable)
• Rancher toolset: Clusters and projects via Steve (management proxy); Norman management API (/v3) for schemas, users, tokens, auth configs, global role bindings, cluster registration tokens, node drivers, cloud credentials, catalogs, cluster repos, feature flags, settings, audit (when exposed); support bundle and generic actions when writes are enabled
• Kubernetes toolset: List/get/create/patch/delete resources by apiVersion/kind; describe (resource + events), events, capacity
• Helm toolset: List/get/history of releases; install, upgrade, rollback, uninstall; repo list
• Fleet toolset: GitRepo list/get/create; Bundle list; Fleet cluster list; drift detection
• Rancher APIs: Same Bearer token for Steve (/k8s/clusters/...) and Norman (/v3/...); no CLI wrappers
• Security: Read-only default, disable-destructive, sensitive data masking (Norman token/credential fields redacted unless --show-sensitive-data)
• Config: Flags, env (RANCHER_MCP_*), or file (YAML/TOML)

Quick start

Install

npm install -g rancher-mcp-server

Cursor

Add to .cursor/mcp.json (project-level) or ~/.cursor/mcp.json (global):

{
  "mcpServers": {
    "rancher": {
      "command": "npx",
      "args": [
        "-y", "rancher-mcp-server",
        "--rancher-server-url", "https://rancher.example.com",
        "--rancher-token", "token-xxxxx:yyyy",
        "--toolsets", "harvester,rancher,kubernetes,fleet"
      ]
    }
  }
}

Restart Cursor after saving. Check Settings → Tools & MCP that rancher is listed and enabled.

Claude Desktop

Add to your Claude Desktop config (claude_desktop_config.json):

{
  "mcpServers": {
    "rancher": {
      "command": "npx",
      "args": [
        "-y", "rancher-mcp-server",
        "--rancher-server-url", "https://rancher.example.com",
        "--rancher-token", "token-xxxxx:yyyy",
        "--toolsets", "harvester,rancher,kubernetes,fleet"
      ]
    }
  }
}

With env vars instead of args

If you prefer to keep the token out of the JSON config:

{
  "mcpServers": {
    "rancher": {
      "command": "npx",
      "args": ["-y", "rancher-mcp-server"],
      "env": {
        "RANCHER_MCP_RANCHER_SERVER_URL": "https://rancher.example.com",
        "RANCHER_MCP_RANCHER_TOKEN": "token-xxxxx:yyyy",
        "RANCHER_MCP_TOOLSETS": "harvester,rancher,kubernetes"
      }
    }
  }
}

Enable write operations

For VM create, snapshots, backups, image/volume create, addon switch, host maintenance mode, VPC create/update/delete, Kubernetes create/patch/delete, Helm install/upgrade/rollback, Fleet gitrepo create/delete, and Norman writes (tokens, users, auth configs, role bindings, cluster registration tokens, cloud credentials, catalog refresh, feature flags, settings, rancher_norman_action, support bundle), add --read-only=false. Delete operations (Norman tokens/bindings/registration tokens/cloud credentials, plus existing toolset deletes) also require --disable-destructive=false (default).

{
  "mcpServers": {
    "rancher": {
      "command": "npx",
      "args": [
        "-y", "rancher-mcp-server",
        "--rancher-server-url", "https://rancher.example.com",
        "--rancher-token", "token-xxxxx:yyyy",
        "--toolsets", "harvester,rancher,kubernetes,helm,fleet",
        "--read-only=false"
      ]
    }
  }
}

Streamable HTTP transport

For web clients or remote access (e.g. Claude Code claude mcp add -t http), add --transport and --port:

{
  "mcpServers": {
    "rancher": {
      "command": "npx",
      "args": [
        "-y", "rancher-mcp-server",
        "--rancher-server-url", "https://rancher.example.com",
        "--rancher-token", "token-xxxxx:yyyy",
        "--transport", "http",
        "--port", "8080"
      ]
    }
  }
}

The server uses the MCP Streamable HTTP transport. The default MCP path is /mcp; connect to http://localhost:8080/mcp (or your server base URL + /mcp). Best supported with Claude Code; Cursor support may vary.

Build from source

If you prefer to build the Go binary yourself:

go build -o rancher-mcp-server ./cmd/rancher-mcp-server

Then reference the binary directly in your MCP config:

{
  "mcpServers": {
    "rancher": {
      "command": "/absolute/path/to/rancher-mcp-server",
      "args": [
        "--rancher-server-url", "https://rancher.example.com",
        "--rancher-token", "token-xxxxx:yyyy",
        "--toolsets", "harvester,rancher,kubernetes,fleet"
      ]
    }
  }
}

Configuration

Harvester tools

List tools accept cluster (required), namespace, format (json|table), limit (default 100), continue (pagination token for next page). Write tools require read_only: false.

Creating a VM on KubeOVN VPC with external internet

Use harvester_vm_create with:

1. network: Name of the overlay network (NAD) linked to a KubeOVN subnet. Create via harvester_network_create (type=kubeovn) then harvester_subnet_create with provider={network}.{namespace}.ovn, vpc=<vpc-name>, and nat_outgoing=true.
2. interface_type: managedtap (recommended for KubeOVN) or bridge. Uses Multus as primary network.
3. subnet: Optional KubeOVN subnet name for ovn.kubernetes.io/logical_switch annotation.

Example: VM on network vswitch1 in namespace default, managedTap interface, subnet vswitch1-subnet:

harvester_vm_create cluster=<cluster-id> namespace=default name=testvm image=<image> network=vswitch1 interface_type=managedtap subnet=vswitch1-subnet

Rancher tools

Rancher tools use the management cluster (local). There is no cluster parameter on these tools.

Steve API (management resources)

Norman API (https://<rancher>/v3/...)

Norman tools call Rancher’s JSON management API. Discover types and collection URLs for your server with rancher_norman_schema_list / rancher_norman_schema_get (schema ids such as user, token, cluster).

Read-only (always registered with the rancher toolset)

When --read-only=false

When --read-only=false and --disable-destructive=false

Norman responses: catalog, cluster repos, audit

• rancher_cluster_repo_list / rancher_cluster_repo_get: Tries Norman /v3/clusterrepos first. If that returns 404 (common), falls back to catalog.cattle.io/v1 ClusterRepo on the local cluster via Steve/Kubernetes, trying namespaces cattle-global-data, fleet-default, fleet-local, cattle-fleet-system. Success JSON includes "_source":"kubernetes_api_fallback". If nothing works, the tool still returns 200-style JSON with "_source":"unavailable" and per-attempt errors—not a hard MCP error—so automation can continue.
• rancher_catalog_list / rancher_catalog_get: If Norman /v3/catalogs is not registered (404), returns JSON with "_source":"unavailable" instead of failing.
• rancher_audit_log_list: If the server returns 404 or 405 (GET not supported), returns JSON with "_source":"unavailable" and _http_status; audit may be disabled or exposed outside Norman.

For catalog data when ClusterRepo is unavailable everywhere, use kubernetes_list on cluster local with api_version catalog.cattle.io/v1 and kind ClusterRepo, or Helm / Fleet tools as appropriate.

Helm tools

All tools take cluster (Rancher cluster ID). Install/upgrade require chart, release; optional repo_url, version, values (JSON).

Fleet tools

All tools use the Rancher management cluster (local). Optional namespace (default: fleet-default). List tools support format, limit, continue (pagination). fleet_gitrepo_create requires name, repo; optional branch, paths. fleet_gitrepo_action supports: pause, unpause, disablePolling, enablePolling, forceUpdate. fleet_gitrepo_clone copies spec from an existing GitRepo to a new name.

Kubernetes tools

All tools take cluster (Rancher cluster ID). List/get support namespace, format (json|table), limit, continue (pagination). Create/patch/delete are gated by read_only and disable_destructive. kubernetes_logs does not support follow (streaming); use tail_lines and since_seconds to limit output. In some Rancher/proxy setups pod logs can return 503 or stream errors; see Troubleshooting.

Setup: Rancher token & Harvester cluster ID

Get a Rancher API token

1. Log in to your Rancher UI.
2. Click your profile/avatar (top right) → Account & API Keys (or API & Keys).
3. Click Create API Key, name it (e.g. mcp-server), then Create.
4. Copy the token once (format like token-abc12:xyz...). Use it as --rancher-token or RANCHER_MCP_RANCHER_TOKEN.

Find your Harvester cluster ID

Harvester tools require the cluster ID (e.g. c-tx8rn) on each call.

• From Rancher UI: Go to Cluster Management → open your Harvester cluster. The URL contains the cluster ID: .../c/<cluster-id>/....
• From API (Steve): curl -s -H "Authorization: Bearer YOUR_TOKEN" "https://YOUR_RANCHER_URL/k8s/clusters/local/v1/management.cattle.io.clusters" | jq '.data[] | {name: .metadata.name}'
• Norman schemas: curl -s -H "Authorization: Bearer YOUR_TOKEN" "https://YOUR_RANCHER_URL/v3/schemas" | jq '.data[0:5].id'

Docker (Streamable HTTP)

For HTTP server mode, use the container image from GitHub Container Registry (ghcr.io). For Cursor/Claude with stdio, use npm (see Quick start).

Run the server and expose the port:

docker run -d -p 8080:8080 \
  -e RANCHER_MCP_RANCHER_SERVER_URL=https://rancher.example.com \
  -e RANCHER_MCP_RANCHER_TOKEN="token-xxxxx:yyyy" \
  -e RANCHER_MCP_TRANSPORT=http \
  -e RANCHER_MCP_PORT=8080 \
  ghcr.io/mrostamii/rancher-mcp-server:latest

Connect clients to the MCP endpoint: http://localhost:8080/mcp (Streamable HTTP; default path is /mcp). Example: claude mcp add -t http rancher http://localhost:8080/mcp

Supported platforms

• macOS (Apple Silicon & Intel)
• Linux (x64 & ARM64)
• Windows (x64)

Troubleshooting

License

Apache-2.0