Desktop repository launches now defer isolated worktree creation until the
first user turn so the CLI owns worktree setup, cwd initialization, and
session metadata. The chat UI surfaces the pre-startup Git phase so users see
when a session is creating a worktree or switching a branch before model
output begins.
Constraint: Desktop must preserve the selected source checkout until a user actually sends a message
Constraint: CLI setup is the canonical owner for worktree creation and cwd initialization
Rejected: Create the worktree eagerly in the desktop session picker | it diverges from CLI session startup and creates worktrees before a conversation exists
Confidence: high
Scope-risk: moderate
Directive: Keep repository session startup routed through CLI worktree flags; do not reintroduce eager desktop worktree creation without testing transcript cwd and cleanup behavior
Tested: bun test src/server/__tests__/sessions.test.ts src/server/__tests__/conversation-service.test.ts
Tested: bun test src/server/__tests__/conversations.test.ts
Tested: bun test src/server/__tests__/conversations.test.ts --test-name-pattern "worktree startup status"
Tested: cd desktop && bun run test -- src/pages/EmptySession.test.tsx
Tested: cd desktop && bun run lint
Tested: cd desktop && bun run build
Tested: git diff --check
Tested: CLI init-only native worktree smoke from feature/rail
Tested: agent-browser UI flow with MiniMax-M2.7-highspeed in a /tmp repository
Desktop sessions now resolve repository launch intent before creation, so users can pick a branch, choose whether to isolate it in a worktree, and get stable error messages instead of silent branch-switch failures. The server owns the Git safety checks and session metadata so the UI and real agent runtime agree on the actual working directory.
Constraint: Direct branch switching must not overwrite or hide uncommitted user changes
Constraint: Desktop worktree branches must stay out of normal branch selection and recent-project labels
Rejected: Let the UI call git directly | server-side checks keep session metadata and runtime launch paths consistent
Rejected: Auto-switch dirty checkouts | users need an explicit isolated-worktree choice to protect local edits
Confidence: high
Scope-risk: moderate
Directive: Do not relax dirty-worktree or checked-out-branch guards without adding equivalent business-flow tests
Tested: ALLOW_CLI_CORE_CHANGE=1 bun run quality:pr
Tested: /tmp business-flow script with dirty checkout, checked-out branch, isolated worktree, missing branch, non-git, missing directory, and real LLM session
Tested: agent-browser desktop UI flow across dirty, checked-out, non-git, branch search, recent-project, and Run scenarios
