MCP lease template

Two declared servers separate the always-available Direct control tools from leased tools whose manifest baseline is Relay. lease_set and lease_status exercise the generic bridge. /plugin-id:mount relay 120 starts renewal; :unmount revokes tools and stops renewal. A bounded before_model hook renews active leases at each model cycle. No timer, hidden transport or new executable is registered dynamically. Expiry while idle leaves tools unavailable until renewed; Direct/Relay changes apply at the next tool assembly. Renewal and command control share a lock; cancellation is saved before its unmount request so a failed request cannot restart renewal.

Change the echo tool, translate metadata, and add cancellation-specific hooks when your workflow owns longer-lived activity. Keep the control server available and verify expiry, disablement, user overrides and stale-call rejection. Read the kit's docs/mcp-lifecycle.md before extending this contract.