Monitor for a Gemini Notebook (ex-NotebookLM) backend/domain migration

On 2026-07-16 Google rebranded NotebookLM → Gemini Notebook (blog). It remains a standalone product (also surfaced in the Gemini app / Search AI Mode), existing links get automatic redirects, and there is no announced API/backend change.

Status: the client still works — verified live post-rebrand (server_info on 0.8.0b4 authenticated cleanly; the full b4 stress test passed). This is a watch item, not a break.

Why watch

A rebrand + active Gemini integration + a new code-execution feature = elevated backend churn over the coming weeks. Our #1 breakage class is exactly Google changing the batchexecute protocol / method ids / domain (CLAUDE.md). If the standalone app is re-homed under gemini.google.com or the app path changes, several things break at once.

Our exposure (mostly contained)

• Base URL is centralized + env-overridable: DEFAULT_BASE_URL / get_base_url() / NOTEBOOKLM_BASE_URL (rpc/types.py, _env). A domain move is a one-module fix, and NOTEBOOKLM_BASE_URL is an emergency stopgap.
• Watch specifically:
  • notebooklm.google.com deprecation / redirect to a Gemini domain.
  • The batchexecute app path /_/LabsTailwindUi/data/batchexecute (the LabsTailwindUi segment is app-specific and would change if re-homed).
  • Origin / X-Same-Domain auth headers — SAPISIDHASH is Origin-bound (a domain change breaks auth if the Origin isn't updated).
  • RPC method ids in rpc/types.py (the volatile obfuscated ids).
  • The notebooklm login browser flow URLs.

Action

• Keep RPC-health CI + nightly E2E green and watched over the coming weeks — they're the tripwire.
• If it breaks: re-capture traffic → update DEFAULT_BASE_URL + Origin + the batchexecute path + method ids; ship a fast-follow.
• No code change needed now.

Filed after the 2026-07-16 rebrand; do-not-implement-yet, monitor-only.