kustomize_dryrun · Kube Lint MCP: Risk & Policy

WHAT IT DOES

What kustomize_dryrun does on Kube Lint

AI agents invoke kustomize_dryrun to trigger actions in Kube Lint. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why kustomize_dryrun needs a policy

This tool executes kubectl commands (even in dry-run mode) against potentially arbitrary Kustomize overlays. While dry-run itself doesn't modify cluster state, the execution of kubectl with complex manifest inputs could trigger unexpected behavior, resource validation errors, or information disclosure about the cluster.

From the tool's definition Tool performs 'building and running kubectl dry-run' operations. The execution of kubectl commands with dry-run flag, while read-only in intent, constitutes code/command execution that could have side effects depending on the cluster state and manifests being…

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

kustomize_dryrun Rate-limited

kustomize_dryrun stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "kustomize_dryrun": {
      "limits": [
        {
          "counter": "kustomize_dryrun_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Kube Lint, so you can run agents against it safely.

FAQ

Questions about kustomize_dryrun

What does the kustomize_dryrun tool do? +

Validate Kustomize overlay by building and running kubectl dry-run\n. It is categorised as a Execute tool in the Kube Lint MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on kustomize_dryrun? +

Register the Kube Lint MCP server in PolicyLayer and add a rule for kustomize_dryrun: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Kube Lint. Nothing to install.

What risk level is kustomize_dryrun? +

kustomize_dryrun is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit kustomize_dryrun? +

Yes. Add a rate_limit block to the kustomize_dryrun rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block kustomize_dryrun completely? +

Set action: deny in the PolicyLayer policy for kustomize_dryrun. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides kustomize_dryrun? +

kustomize_dryrun is provided by the Kube Lint MCP server (sophotechlabs/kube-lint-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.