Hey, thanks for the detailed feature request and the syntax example. That’s really helpful.
Confirming the current behavior: custom subagents inherit all MCP tools from the parent, and the only way to restrict it is the readonly flag, which blocks MCP entirely with no per-tool control. Per-server or per-tool whitelisting via frontmatter isn’t supported right now.
We’re aware of the gap, and we’re discussing the spec internally, but I can’t share a concrete timeline or the final config format yet. I’ll pass along your example with an mcp_servers block and a tool-level array as a clear signal. The use case is easy to see and helps with prioritization, especially for token efficiency and read-only safety.
A couple related threads if you want to follow along:
- Subagent control via rules and settings
- Workspace- or profile-scoped Cursor config (rules, skills, subagents, MCP)
If there’s an update on the design, I’ll post it here.