extension/packages/outlook

Hanzo AI for Microsoft Outlook

A mail add-in that puts Hanzo AI inside Outlook — desktop (Windows/Mac), new Outlook, and Outlook on the web. Open a message, click the Hanzo button on the ribbon, and:

• Summarize thread — parties, dates, defined terms, obligations, open questions.
• Draft reply — a professional reply in the sender's tone; open it in a reply window or insert it into the compose body.
• Extract deadlines & action items — every due date and task, with owner and date.
• Explain plainly — plain-language read-out plus the risks/obligations/deadlines.

This is the highest-value surface for a law office after Word: the inbox is where deadlines and commitments actually arrive.

It reuses the same backend as everything else Hanzo: model calls go through api.hanzo.ai/v1 (OpenAI-compatible, streamed), sign-in is Hanzo IAM (hanzo.id, authorization-code + PKCE, HIP-0111) — the mail add-in shares the hanzo-office IAM client. No new API surface.

What it reads / writes

• Read mode (a received message is open): reads the body (item.body.getAsync as plain text), subject, and from — the input to summarize / extract / draft. The write path is Draft reply, which opens a reply form (item.displayReplyForm) pre-filled with the AI text.
• Compose mode (a reply / new message is open): Insert into message writes the draft into the compose body — prepended above the quoted thread (item.body.prependAsync) or replacing the body (item.body.setSelectedDataAsync).

Architecture (DRY with the Office task pane)

The pure, host-agnostic core is identical to @hanzo/office-addin and unit-tested here:

• config.ts — the api.hanzo.ai/v1 gateway endpoints + roaming-settings keys.
• chat.ts — ask / askStream (SSE) / listModels and the request/response shaping.
• auth.ts — the @hanzo/auth OAuth2+PKCE core wired to Office roamingSettings, plus the pasted sk- API-key path.

The only Outlook-specific module is outlook-host.ts: the mailbox glue (Office.context.mailbox.item) and its pure shaping helpers — stripHtml, collapseWhitespace, shapeMessage, formatFrom, mailMode — which are what the tests cover. The Office.js calls themselves are thin.

Build

pnpm --filter @hanzo/outlook-addin build      # production (base https://outlook.hanzo.ai)
pnpm --filter @hanzo/outlook-addin test        # vitest
pnpm --filter @hanzo/outlook-addin typecheck   # tsc --noEmit

The build stamps the hosting base URL into dist/manifest.xml. Outlook loads the task pane from an HTTPS origin declared in the manifest; the same origin serves auth-callback.html (the IAM redirect, registered on the hanzo-office IAM client). Override the base for local dev:

HANZO_OUTLOOK_BASE=https://localhost:3000 pnpm --filter @hanzo/outlook-addin build

Then serve dist/ over HTTPS at that base:

npx office-addin-dev-certs install   # trust a localhost cert (once)
cd packages/outlook/dist && node serve.mjs   # https://localhost:3000

Sideload (no store needed)

A mail add-in installs differently from a Word/Excel task pane — you add it through the mailbox, not "Insert → Add-ins".

• Outlook on the web / new Outlook: Settings ⚙ → Mail → Customize actions is not the path — use Get Add-ins (the "…" / Apps menu on an open message) → My add-ins → Custom Addins → Add a custom add-in → Add from file, pick dist/manifest.xml. (dist/ must be served at the base URL over HTTPS.)
• Outlook desktop (Windows/Mac, classic): Home → Get Add-ins → My add-ins → Custom add-ins → Add a custom add-in → Add from file → dist/manifest.xml. Requires a Microsoft 365 / Exchange Online mailbox (sideloading a custom mail add-in from file needs the mailbox to allow it).
• Open any message: the Hanzo AI button appears on the message ribbon (read view); open a reply/compose and it appears there too.

Whole firm (recommended for a law office)

An M365 admin deploys the add-in org-wide — every user gets the Hanzo button with no per-person sideload:

Microsoft 365 admin center → Settings → Integrated apps → Upload custom apps → Provide link to manifest file (host manifest.xml at the base URL) or upload the manifest, choose the users/groups, and deploy. Centralized Deployment covers Outlook desktop, web, and Mac.

Publish (AppSource — public listing)

dist/manifest.xml is a valid, submittable Mail add-in manifest (validate with npx office-addin-manifest validate dist/manifest.xml). To list publicly:

1. dist/ is already hosted: CI publishes it on every push to main (the repo's hanzo.yml sites: entry outlook, prefix s3://hanzo-sites/hanzo/outlook), and universe static-sites.yaml routes outlook.hanzo.ai to it.
2. The hanzo-office IAM client (universe iam-provision.yaml) allows the redirect https://outlook.hanzo.ai/auth-callback.html.
3. Submit https://outlook.hanzo.ai/manifest.xml through Microsoft Partner Center → Marketplace offers → Office add-in (needs a Partner Center account
   • Microsoft's validation pass).

Requirements

• Mailbox requirement set 1.5+ (declared in the manifest) — covers current Outlook desktop, Mac, and Outlook on the web / new Outlook.
• Permissions: ReadWriteItem — reads the open item and writes the reply draft; it never touches other items or makes EWS calls (so not ReadWriteMailbox).