400 error: tool_call_ids not responded to after /add-dir command

Summary

After running /add-dir with a path argument, Claude Code returns a 400 error indicating that tool call IDs were not properly followed up with tool response messages.

Error message

I'm sorry, I encountered an error processing your message: 400 An assistant message with 'tool_calls' must be followed by tool messages responding to each 'tool_call_id'. The following tool_call_ids did not have response messages: call_YKZmfR3hZVGYeWhFkrpMwgJ4, call_rHQ1y3lvfHJkeod7ffHg5b3i, call_cOUOlwRM8RQh1eDR84kykaiB

Steps to reproduce

1. Open Claude Code in a project directory
2. Run /add-dir "C:\Users\19095\Documents\GitHub\f2i-websites"
3. The command fails with the path-not-found error, then immediately presents the 400 error above

Expected behavior

The /add-dir command should either successfully add the directory or return a clear error message without causing a broken tool_call chain.

Actual behavior

The command returns a 400 API error caused by tool calls being made without their corresponding tool response messages being included in the conversation.

Environment

• OS: Windows 11
• Shell: PowerShell 5.1 / Git Bash
• Command attempted: /add-dir "C:\Users\19095\Documents\GitHub\f2i-websites"

Notes

The error suggests the /add-dir skill or handler issued multiple tool calls (3 tool_call_ids) but the results were never fed back to the model, leaving the conversation in an invalid state.