💡 New script: gmail-digest (customizable email digest with optional AI summaries)

[github-actions[bot]]

Summary

A standalone script that generates periodic email digests of important threads from configurable Gmail labels, with optional Gemini-powered summaries. Users configure which labels to scan, frequency, and recipients via the deploy page. The digest email contains thread subjects, senders, dates, and snippet previews — with an optional AI summary layer using the Gemini API via GAS's Vertex AI service.

Market Signal

Gmail AI Overviews launched in 2026 but require paid Google Workspace and only work in-app — they cannot be delivered as a shareable email or archived. AI email add-on installs grew 200% in the Workspace Marketplace (2023–2025). Existing open-source email digest scripts (e.g., gmail-email-summary-script) are primitive and lack browser-based deployment. The calendar-to-briefing-doc script in this project validates the "periodic email intelligence" pattern with 249 tests and 99% coverage. Superhuman (acquired by Grammarly, June 2025) and Shortwave both prove market demand for email intelligence — but at premium prices.

User Signal

Email overload is the #1 productivity complaint across user segments. This project already excels at email processing (gmail-to-drive-by-labels) and email delivery (calendar-to-briefing-doc). A digest script fills the gap between archiving emails and summarizing them. Users want customizable email intelligence they control, not vendor-locked AI features that require paid subscriptions.

Technical Opportunity

Mirrors calendar-to-briefing-doc's architecture almost exactly: timer trigger → scan data → format briefing → email recipients. Can reuse getCleanBody() from gas-utils.js for email text cleaning. Optional Gemini integration via GAS's Vertex AI advanced service or UrlFetchApp + API key. Config shape mirrors BRIEFING_CONFIGS: [{labels, frequency, recipients, enableAiSummary, summaryLength}]. The shouldRunNow() schedule pattern is directly reusable.

Assessment

Dimension	Score	Rationale
Feasibility	high	Mirrors calendar-to-briefing-doc architecture; reuses getCleanBody() and schedule patterns
Impact	high	Email overload is universal; free alternative to paid AI Overviews; deliverable + shareable
Urgency	high	AI email market is booming (200% Marketplace growth); competitive moat via free + customizable

Adversarial Review

Strongest objection: Gmail already has native AI Overviews that summarize threads. Why build a separate tool?

Rebuttal: (1) AI Overviews only work in the Gmail UI — they can't be delivered as a forwarding-friendly email. (2) They require paid Workspace; this is free. (3) This is customizable: specific labels, specific frequency, specific recipients, specific summary style. (4) The digest can feed into other workflows (archive to Docs, share with team). The key differentiator is ownership and customizability.

Suggested Next Step

Implement non-AI digest first (label scan + email formatting), then add Gemini summarization as an opt-in config flag. Reuse calendar-to-briefing-doc patterns for scheduling, formatting, and email delivery.