Agent Teams: Idle teammate spawn burns ~4 turns of tokens before any productive work

[deepakpatnaik1]

Description

When spawning a teammate in Agent Teams (experimental), the system generates multiple unnecessary round-trips before any actual work can begin. This burns tokens with zero productive output.

Steps to Reproduce

1. Create a team with TeamCreate
2. Spawn a teammate using the Task tool with run_in_background: true and team_name set
3. Do not assign any task yet — just spawn

What Happens

The following sequence fires automatically:

1. Teammate spawns and sends a "reporting in, ready for tasks" message to the lead
2. Lead's turn fires to acknowledge the teammate's check-in message (token cost)
3. Teammate goes idle, system sends an idle_notification to the lead
4. Lead's turn fires again to acknowledge the idle notification (token cost)

That's ~4 turns of token burn (2 teammate, 2 lead) with zero productive output — the teammate hasn't done anything yet.

Expected Behavior

Spawning a teammate should be silent until work is assigned. Possible fixes:

• Suppress the initial check-in message — the lead already knows the spawn succeeded from the Task tool result
• Don't deliver idle notifications to the lead until the teammate has completed at least one task — going idle immediately after spawn is the default state, not news
• Don't force the lead to "respond" to teammate system messages — idle notifications and check-ins shouldn't consume a lead turn

The ideal flow: spawn teammate → assign task → teammate works → teammate reports back. No intermediate chatter.

Environment

• Claude Code with Agent Teams experimental feature enabled (CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS: "1")
• macOS (Darwin 25.2.0)
• Model: Claude Opus 4.6

Impact

Every agent team session starts with wasted tokens. For teams with multiple teammates, this multiplies — N teammates = ~2N wasted lead turns just from spawn overhead. This makes the "spawn now, assign later" pattern (which is natural for a team lead) unnecessarily expensive.