The special agent for kubernetes consists of two files.
First file is inside “~/share/check_mk/agents/special/” - agent_kubernetes
This one only loads the real agent file from “~/lib/python/cmk/special_agents/agent_kubernetes”
Copy the file from “~/lib/python/cmk/special_agents” to “~/local/share/check_mk/agents/special/”, make it executable.
Now you can play around with this agent and your configured kubernetes hosts should use your modified version.