[FEATURE] Feature: API/CLI to programmatically open new Claude Code conversation sessions in VS Code

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

Add a way to programmatically open a new Claude Code conversation session (panel/tab) in VS Code from within an existing session or from a CLI subprocess.

Use Case

When building agentic workflows with recurring tasks (e.g. /loop or CronCreate), it's useful to spawn each triggered task in its own isolated conversation session visible in the VS Code UI — rather than accumulating all output in the current session thread.

Concrete example: A cron job monitors a Slack channel for new alerts. When an alert arrives, the ideal UX is for a new Claude Code conversation tab to open in VS Code focused on that specific alert, where the user can interact with it independently.

Current Workaround

• Using the Agent tool spawns a subagent, but its output flows back into the current session thread
• claude -p "..." spawns a headless subprocess (not visible in VS Code UI)
• Opening a new terminal tab with claude works but is not integrated into the VS Code panel UI

Proposed Solution

One or more of:

1. VS Code command: claude.openNewSession (callable via code --command) that opens a new conversation panel with an optional pre-filled prompt
2. CLI flag: claude --new-session "prompt" that opens a new interactive session in whatever IDE/UI is currently active
3. IPC/socket API: a local socket or named pipe that the current Claude Code instance listens on, allowing subprocesses to request a new session be opened

Alternative Solutions

_No response_

Priority

High - Significant impact on productivity

Feature Category

CLI commands and flags

Use Case Example

_No response_

Additional Context

_No response_