0.2.0-rc.2 withdrew every catalog/subagent seam this fork was written against, and all three calls degraded to silent no-ops: openSubagent(address) -> gone setSubagentCatalogOpen(id, open) -> gone refreshSubagents(id) -> gone The host's own subagent UI (dsh-client-ui-subagent) rebuilds a parent's child catalog with `sessions.refreshProjections(parentSessionId)`, so that is the only kick that still exists. Wire it into `observe()` and the catalog retry button, keeping the legacy names as fallbacks for older hosts. Without it the root catalog never hydrated: the page sat on "loading" or degraded to synthesized summary rows. Also document what the investigation settled: - docs/subagent-state-enumeration.md: the full state model (catalog child / diagnostic / session / job / sidechat) and proof that this fork already renders it 1:1 with upstream. - docs/plugin-conventions.md: the hard rules another sidebar plugin must follow (host schemastery, volatile prefs, ns = profile entry id, no colons in tab ids, never read a volatile field directly) plus the withdrawn-API replacement table and a pre-release checklist. - docs/feedback-0.2.0-rc2-contract-gaps.md: gaps 2/3 reframed. The ask is documenting the official paths (open(childSessionId) / refreshProjections(id)), not adding new APIs. Gates: typecheck 0, lint 0, build 0, test 131 files / 1385 passed.