Idle notification gives no signal that a teammate's finished output still needs to be explicitly requested

**Environment:**
- Claude Code CLI version 2.1.234 (commit `7215ba60b06d`), macOS (darwin-arm64)
- Model: Claude Sonnet 5
- `CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS=1`, explicitly set in `settings.json` (not a default/ambient setting)

**Not filing this as a broken-behavior bug** — I confirmed the current behavior matches the docs at `code.claude.com/docs/en/agent-teams`, which state plainly: *"The notification doesn't carry the teammate's output; a teammate shares results by messaging the lead or updating the shared task list."* So this is working as designed. Flagging it anyway because it's a real, repeated point of friction in practice.

**What happened:** Across a single session, I dispatched many background teammates for research tasks. Every single one, without exception, ran to completion, went idle, and sent nothing — just a bare `idle_notification` with no output attached. To get the actual result, I had to separately message the teammate and explicitly ask it to send its report. This wasn't a one-off; it happened for every teammate, every time, with no variation.

**Why this is a real UX problem in practice, even though it's documented:**
- Nothing in the idle notification itself hints that a follow-up ask is needed — it reads exactly like a normal "task finished" signal, so the natural first reaction is to assume the result should already be there.
- The user watching the session has no way to tell, from the notification alone, whether the teammate produced nothing, produced something that's stuck, or simply hasn't sent it yet — all three look identical.
- Because it happens 100% of the time with no exceptions, it reads less like an edge case to plan around and more like a missing step in the normal completion flow.

This is a documentation/design note being surfaced as lived friction, not a request to change intended behavior — but if there's an appetite for a smaller ergonomic improvement (e.g., the idle notification itself hinting "ask this teammate to send its result"), this is the use case motivating it.

Start with code.claude.com/docs/en/agent-teams and the documented idle_notification behavior, then reproduce the flow using the stated Claude Code CLI version and agent-team setting. Done requires an agreed scope for either clarifying the follow-up step or changing the notification, since the issue does not identify a source file or test.

Rédigé par le modèle d'indexation à partir du texte de l'issue.