patch_deployment · K8s MCP: Risk & Policy

WHAT IT DOES

What patch_deployment does on K8s MCP

AI agents use patch_deployment to create or update resources in K8s MCP — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your K8s MCP environment.

WHY IT NEEDS A POLICY

Why patch_deployment needs a policy

Patching a deployment modifies its configuration (e.g., replicas, image, environment variables) in a potentially reversible way. However, misuse could cause outages or introduce malicious configurations into running workloads, making the blast radius high. It does not inherently delete or irreversibly destroy data, so Write is the most appropriate category over Destructive, though the impact can be significant.

From the tool's definition 'Patch a deployment with custom data' — modifies an existing Kubernetes deployment

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

patch_deployment Rate-limited

patch_deployment stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "patch_deployment": {
      "limits": [
        {
          "counter": "patch_deployment_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches K8s MCP, so you can run agents against it safely.

FAQ

Questions about patch_deployment

What does the patch_deployment tool do? +

Patch a deployment with custom data. It is categorised as a Write tool in the K8s MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on patch_deployment? +

Register the K8s MCP server in PolicyLayer and add a rule for patch_deployment: 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 K8s MCP. Nothing to install.

What risk level is patch_deployment? +

patch_deployment is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit patch_deployment? +

Yes. Add a rate_limit block to the patch_deployment 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 patch_deployment completely? +

Set action: deny in the PolicyLayer policy for patch_deployment. 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 patch_deployment? +

patch_deployment is provided by the K8s MCP server (rahul007-bit/k8s-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.