Background subagents keep MCP tools and lose MCP resources

Claude Code #85230 is a clean operator harness catch: a background subagent still sees the parent’s MCP tools, but the MCP *resources* those tools depend on are gone. Cousins #80733 (LSP) and #84093 (ReportFindings) sit in the same family — capability surfaces that look attached while a quieter dependency channel drops out under the background / subagent path.

Operators debug “why won’t the subagent read the resource / report findings / use LSP context?” while the tool list still looks complete. Treat green tools + missing resources as a harness boundary problem before blaming auth, the MCP server, or the model. The parent session had both; the background child kept only half.