Claude Desktop Feature Request: Session Start Hook for Automatic Initialization

The Problem: User Preferences Isn't a Startup Script

The Profile/User Preferences field in Claude Desktop Settings appears to be initialization but isn't. It's instructions — text injected into context that Claude reads and follows when you send your first message. Nothing executes automatically on session open. Claude doesn't do anything until you send something.

For users building context-loading systems — BRAIN.md files, session memory MCP servers, project state files — this means every session requires a manual trigger. You open the app, type your callsign or trigger phrase, and then initialization fires. It works as a workaround but isn't a feature.

The Proposed Solution: "On Session Start" Execution Field

A dedicated field in Settings — separate from User Preferences — where instructions execute automatically when a new conversation opens, before the user types anything.

Example from the source:

[On Session Start]
Run session-memory:load_context with brain_path="G:\My Drive\MY_BRAIN.md"
If successful: summarize WHERE WE ARE RIGHT NOW and ask "What are we building today?"
If failed: note the failure and continue

Why This Matters

Claude Desktop's value proposition over claude.ai browser is local execution reach — MCP servers, filesystem access, shell commands. A session start hook makes that reach immediately visible on every session open.

Currently, the first experience of a new Claude Desktop session is: blank chat window, waiting for input (same as the website). With a session start hook and a BRAIN.md file: Claude opens already briefed, knowing your projects, current status, what's blocked, and what's next. The first thing you see is Claude telling you where you are — not a blank cursor.

The MCP infrastructure already supports this functionality. The request is for Anthropic to provide a reliable execution moment to invoke it.

Prior Art Examples

• .bashrc / .zshrc — runs on terminal open
• VSCode extension activation — fires on app launch
• Browser extension content scripts — fire on page load
• Raycast — runs scripts on launch or schedule

"Run something when the thing opens" is described as one of the most basic power-user needs in any tool, with Claude Desktop being the only one in this list that doesn't support it.