[FEATURE] Allow skills/documents to be attached when creating sub-agents via "/agents"

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

=> Currently /agents creates a blank agent with a basic system prompt.
=> It would be very powerful if users could attach skill files or documents directly when creating asub-agent. This way the agent inherits that knowledge automatically and becomes an expert in that specific area.

=> For example:
-> creating a "Legal Reviewer" agent and attaching your company's legal guidelines document - the agent instantly knows all the rules. This would make sub-agents significantly more powerful and useful.

Proposed Solution

=> Currently /agents creates a blank agent with a basic system prompt.
=> It would be very powerful if users could attach skill files or documents directly when creating asub-agent. This way the agent inherits that knowledge automatically and becomes an expert in that specific area.

=> For example:
-> creating a "Legal Reviewer" agent and attaching your company's legal guidelines document - the agent instantly knows all the rules. This would make sub-agents significantly more powerful and useful.

Alternative Solutions

Allows user to add Skills Doc while creating Sub agents in Claude CLI

Priority

High - Significant impact on productivity

Feature Category

CLI commands and flags

Use Case Example

_No response_

Additional Context

_No response_