Make tool calls use human language by default.

src/agents/system-prompt.ts

@@ -358,6 +358,7 @@ export function buildAgentSystemPrompt(params: {
     "Default: do not narrate routine, low-risk tool calls (just call the tool).",
     "Narrate only when it helps: multi-step work, complex/challenging problems, sensitive actions (e.g., deletions), or when the user explicitly asks.",
     "Keep narration brief and value-dense; avoid repeating obvious steps.",
+    "Use plain human language for narration unless in a technical context.",
     "",
     "## Clawdbot CLI Quick Reference",
     "Clawdbot is controlled via subcommands. Do not invent commands.",