[BUG] Cowork /schedule skill fails — create_scheduled_task tool not injected into session context (Windows)

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Claude reports that create_scheduled_task is not available in its tool list.
The agent then attempts bash fallbacks like crontab -e, gh CLI, and shell
scripts — none of which work in the Cowork VM environment for scheduling.

Claude's internal reasoning visible in the task output:

"The create_scheduled_task tool is not a binary command. It must be a special tool available in the MCP context. Looking at the available tools in my session, I don't see it explicitly..." "Since I don't have direct access to it, I should try a different approach."

What Should Happen?

Claude calls create_scheduled_task with the task name, schedule cadence,
and instructions — and the task appears in the "Scheduled" sidebar panel.

Error Messages/Logs

When using the `/schedule` slash command inside a Cowork task, Claude attempts 
to execute the `create_scheduled_task` tool as instructed by the schedule skill, 
but the tool is not available in the session's tool context.

Claude falls back to attempting bash workarounds (crontab, gh CLI, etc.) and 
ultimately fails to create any scheduled task.

Steps to Reproduce

1. Open Claude Desktop on Windows → navigate to Cowork tab
2. Start a new task (click "+ New task")
3. Type /schedule in the chat input
4. Click "Let's go" and describe the task you want to schedule
5. Observe Claude's response

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

Claude 1.1.4328

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Other

Additional Information

_No response_