Per-agent MCP scoping

[nineluj]

Hi, within my workflow I'm trying to set up a dedicated Kubernetes subagent that has access to an MCP server that provides it tools to query information about my Kubernetes clusters. But I want to enable the MCP globally since it's not useful for the other agents (code, plan, explorer, etc).

Currently the mcpServers config is global only, so I can't scope the MCP to just that one agent. The workarounds I found don't seem to ideal:

1. Set disabledTools per agent: this works, but there's no wildcard or regex support so I'm having to write a long list of disabled tools for each of the agents. Also, if the MCP adds a new tool then I would need to go back and re-update all the agent configs.
2. Using a preCallHook to deny execution based on the agent. This is not ideal since the agents still get their contexts bloated with the MCP tool info.
3. Use the MCP disabled: true setting: this toggles it off globally, and I haven't found a way to re-enable it for a single agent.

Is there a pattern that I'm missing, otherwise I could put in a feature request for this. Thanks in advance for your time and attention!

[ericdallo]

@nineluj you could have something like:

{
  "agent": {
    "code":       {"toolCall": {"approval": {"deny": {"k8s-mcp": {}}}}},
    "plan":       {"toolCall": {"approval": {"deny": {"k8s-mcp": {}}}}},
    "kubernetes": {"mode": "subagent", ...}  // sees k8s-mcp normally
  }
}

That would still offer the tool but when used it would be denied, but I get is not the ideal c/c @zikajk

[ericdallo]

Done, next release will support MCP server names and regexes in disabledTools, and disabledTools in agent markdown frontmatter:

{
  "agent": {
    "code": {"disabledTools": ["k8s-mcp"]},
    "plan": {"disabledTools": ["k8s-mcp"]}
  }
}

You still set it per agent, but a server name entry covers all its tools, current and future.

[nineluj]

Awesome, this would be perfect. Thank you @ericdallo !