bug: InterAgentBus async fails silently when named session ID is stale (after CLI update/cache clear)

[alexeymorozua]

Summary

When Claude CLI is updated or its session cache is cleared, named session IDs stored in named_sessions.json become invalid. The InterAgentBus attempts to resume these stale sessions and fails silently — the calling agent receives no response and no error.

Steps to Reproduce

1. Use ask_agent_async.py to send a message between agents (e.g., main → sonic)
2. Update Claude CLI or clear its session cache
3. Send another async message — it appears to succeed (returns task_id) but no response is ever delivered

Observed Behavior

• ask_agent_async.py returns a task_id immediately (looks like success)
• Bus internally attempts claude --resume <stale_session_id>
• Claude CLI outputs: No conversation found with session ID: <id>
• Bus exits with empty output (exit=1), delivers nothing to the caller's Telegram chat
• No error or warning is shown to either agent

Expected Behavior

When No conversation found with session ID is returned, the bus should:

1. Discard the stale session ID
2. Start a fresh session (without --resume)
3. Deliver the response normally

Workaround

Manually reset session_id to "" in:

• ~/.ductor/named_sessions.json — sessions from main agent
• ~/.ductor/agents/<name>/named_sessions.json — sessions from each sub-agent

After reset, the next call creates a fresh session automatically.

Environment

• Ductor: v0.15.0
• Claude CLI: updated from 2.1.76 → 2.1.79 (triggered the issue)
• Multi-agent setup: main + sonic agents

Impact

All async inter-agent communication breaks silently after any Claude CLI update. The only symptom visible to the user is that async responses never arrive.

Co-Authored-By: Claude Sonnet 4.6 noreply@anthropic.com