- CLI: After reload, refreshes self.agent.tools and valid_tool_names
so the model sees updated tools on its next API call
- Both CLI and Gateway: Appends a [SYSTEM: ...] message at the END
of conversation history explaining what changed (added/removed/
reconnected servers, tool count). This preserves prompt-cache for
the system prompt and earlier messages — only the tail changes.
- Gateway already creates a new AIAgent per message so tools refresh
naturally; the injected message provides context for the model