5 items
Substack writing editor enhancement with AI-assisted title, opening, outline, and SEO check using your own API key. Have you ever struggled with finding the right title, writing an engaging opening, or optimizing your Substack newsletter for higher open rates? Substack-AI+ adds an AI writing assistant sidebar to the Substack composer. Using your own Claude / OpenAI API key, you get suggestions tailored to your writing. Features - Title suggestions — Multiple title candidates optimized for newsletter open rates (AI; your API key) - Opening paragraphs — Several opening styles (problem-first, TL;DR, story hook) to start strong (AI) - Outline drafting — Suggested H2 section structure for your post (AI) - Readability check — Local analysis (no API key): character / sentence counts and long-sentence hints - SEO keyword check — Local keyword density and title-inclusion check (no API key) - Multi-AI support — Claude and OpenAI (GPT) selectable - Privacy first — Your content goes only to your chosen AI provider. No Substack-AI+ servers. Pricing - Free: Up to 10 generations per day, all features, using your own API key (transparent running cost). - Pro ($5 / month): Unlimited AI generations plus prompt template library, generation history, and more Pro features. Upgrade via "Upgrade to Pro" in the extension popup (ExtPay / Stripe). Cancel anytime from the portal. How it works 1. Install from the Chrome Web Store 2. Open your Substack post composer (your-publication.substack.com/publish/post). The AI sidebar appears automatically on the right side of the editor (no API key needed to see it). 3. Try Readability or SEO check in the sidebar right away. These run locally with no API key. 4. For AI generation (Titles, Opening, Outline), click the toolbar icon to open Settings and enter your own Anthropic (Claude) or OpenAI API key. 5. Draft, get AI assistance, and publish. Note: the toolbar icon opens Settings (for your API key). The writing sidebar is injected into the Substack composer page automatically. Open a post to see it; it is not opened from the toolbar icon.
Jun 23, 2026
rating_count is the Chrome Web Store ratings count, not a written-review count.
Media assets
Screenshots and videos on the listing.
Has promo video
Whether the listing includes at least one video.
Languages
Declared language locales.
Developer website
Listing exposes a developer website URL.
Contact email
Listing exposes a contact email.
Keyword in name
Case-insensitive substring match in the name.
Keyword in description
Case-insensitive substring match in the description.
Keyword occurrences in description
Count of case-insensitive occurrences in the description.
Category user-count percentile
Share of same-category extensions with fewer users (null if unknown).
These are transparent listing completeness / keyword signals, not a prediction of Chrome Web Store search ranking.