A plugin that finished loading after an adapter connected never got its platform
handlers (slash commands, button callbacks, inbound transforms) registered until a
gateway restart, silently. Three pieces, one seam shared by every surface:
1. Discovery listener: PluginManager.on_plugin_loaded(cb) fires from INSIDE
discover_and_load for the plugins a sweep newly loaded (diff of the loaded set),
with a per-plugin activation summary (hermes_cli/plugins_activation.py):
activated_now {gateway_commands, gateway_transforms, hooks, callbacks} vs
deferred {tools, prompt, mcp_servers}. Every mid-run load path now performs a real
discover_plugins(force=True): CLI install/enable (via the gateway), Desktop/TUI
plugins.manage install/toggle/update, dashboard REST install, tool-triggered
force re-discovery, the new `reload-plugins` control-socket verb. A non-forced
discover_plugins() short-circuits on _discovered, which is why reload.mcp after
a mid-run install used to reload the OLD server set.
2. Idempotent re-wire: BasePlatformAdapter.rewire_plugin_handlers() runs only
factories not yet wired on the live native client (keyed (plugin, qualname);
a force reload hands back new function objects). Telegram hoists late handlers
ahead of core's catch-all filters.COMMAND / CallbackQueryHandler (PTB dispatches
the first match per group) and re-wires on the transient-init rebuild; Slack
dedupes register_slack_action_handler per AsyncApp. The gateway runner
subscribes per served profile and re-wires on the loop.
3. Scope limit + honest messaging: handlers only. Tools/prompt stay deferred to
the next session (prompt-cache invariant), MCP servers to mcp.reload; the CLI
hint and plugins.manage results (activation, gateway_reloaded,
restart_required only when no gateway answered) say exactly that.