Agent teams (CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS) ignore modelOverrides when spawning subagents

Summary

When agent teams spawn subagent processes via tmux, the --model CLI flag passed to each subprocess uses a hardcoded us.anthropic.* model ID. The modelOverrides mapping defined in settings.json is not applied to this flag, causing 400 errors on Bedrock setups that require a different regional prefix (e.g. eu.).

Environment

• Claude Code version: 2.1.87
• Feature flag: CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS=1
• Provider: AWS Bedrock, eu-central-1 via a reverse proxy (ANTHROPIC_BEDROCK_BASE_URL)

Reproduction

settings.json contains:

{
  "env": {
    "CLAUDE_CODE_USE_BEDROCK": "1",
    "ANTHROPIC_MODEL": "eu.anthropic.claude-sonnet-4-6"
  },
  "model": "eu.anthropic.claude-sonnet-4-6",
  "modelOverrides": {
    "us.anthropic.claude-opus-4-6-v1": "eu.anthropic.claude-opus-4-6-v1",
    "claude-opus-4-6": "eu.anthropic.claude-opus-4-6-v1"
  }
}

Trigger an agent team (e.g. "create an agent team for X"). Claude Code spawns subagents via tmux with commands like:

env CLAUDECODE=1 CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS=1 \
  /Users/fedele1/.local/share/claude/versions/2.1.87 \
  --agent-id ... --agent-name ... --team-name ... \
  --agent-type general-purpose \
  --dangerously-skip-permissions \
  --model us.anthropic.claude-opus-4-6-v1

Expected behavior

The spawner should look up us.anthropic.claude-opus-4-6-v1 in modelOverrides before building the subprocess --model argument and pass eu.anthropic.claude-opus-4-6-v1 instead.

Actual behavior

Each subagent starts with --model us.anthropic.claude-opus-4-6-v1 verbatim. The child process does not apply modelOverrides to the CLI-provided model ID, so the API call reaches the gateway with the wrong model string:

API Error (us.anthropic.claude-opus-4-6-v1): 400 The provided model identifier is invalid.
Try /model to switch to us.anthropic.claude-1-20250805-v1:0.

All three spawned agents fail immediately and the team is unusable.

Notes

• The parent session correctly uses eu.anthropic.claude-sonnet-4-6 (set via "model" in settings.json).
• modelOverrides works as expected for interactive model selection in the parent session.
• The subagent spawn command uses the absolute binary path, so a shell PATH wrapper cannot intercept it.
• The issue is specific to the agent teams spawner not consulting modelOverrides when constructing the --model flag for child processes.