Self-Host AI Inside Excel, Word, PowerPoint & Outlook
A self-hosted Office add-in wired to your own model gateway — all four hosts, data never leaves your network, zero pivot dependency. Financial modeling, contract review, and email handling stay in-house.
Where enterprises actually get stuck
The classic dilemma of putting AI into Office: official Copilot routes through Microsoft's cloud, so contracts, financial models, and diligence materials fail compliance the moment they leave the network; yet rolling your own stalls on "where does the add-in even come from" — nearly every Office add-in loads from some SaaS origin by default and phones home on first launch, which hands the data-sovereignty problem right back.
Excel financial models, Word contracts, and Outlook threads are exactly the things you must not leak and most want to accelerate.
How GateLLM does it
GateLLM ships a standalone, self-contained Office add-in: the pre-bundled add-in SPA is served from your own HTTPS static host, the manifest points at your origin, and at runtime it talks directly to your own model gateway.
Across four hosts (Excel / Word / PowerPoint / Outlook) it bundles 33 domain skills (financial modeling, contract review, inbox triage, etc.), and combined with your BYOK gateway, sensitive data stays entirely in-network.
Runtime dependency on pivot is zero — not even first launch phones home.
5 levers that actually land
- Self-hosted add-in: pre-bundled SPA served over your own HTTPS, manifest pointing at your origin, zero pivot dependency at runtime
- 33 bundled skills across four hosts: Excel financial modeling (DCF / LBO / 3-statement), Word contract review (playbook-graded / redline), Outlook inbox (triage / meeting-prep)
- Entra SSO + gateway auth: entra_sso turns the user's Entra token directly into the gateway Bearer, so auth and billing track the real user
- Purview label gating: access_policies match sensitivity-label GUIDs to block addin.access / file.upload, disabling the add-in or attachment upload on confidential docs
- Data stays local: chat history and config live in the browser's local storage with no server copy; a read-only export script audits, and swapping manifests keeps data