ShroomPen: BYOK AI Writing Assistant icon

ShroomPen: BYOK AI Writing Assistant

by ivan.balshalapau · shroompen.com · Communication
Established publisherManifest V3 Free
View in Chrome Web Store Data as of 15 Oct 2026

Reply, rewrite, fix grammar and translate in any text box with your own API key: OpenRouter, OpenAI, Gemini, Claude or Ollama.

Users
34
+24 in 30 days
Rating
5.0 / 5
unchanged in 30 days
Ratings
1
0 in 30 days
Store rank
#124K
#103K among extensions
Version
0.0.4
updated 2 Oct 2026

Users

monthly, 2 months
01734Aug 2026Oct 2026Oct 2026
Latest, 15 Oct 2026: 34 usersMove the mouse over the chart for any month

Ratings count

monthly, 2 months
001Aug 2026Oct 2026Oct 2026
Latest, 15 Oct 2026: 1 ratingsMove the mouse over the chart for any month

The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.

About ShroomPen: BYOK AI Writing Assistant

ShroomPen is an AI writing assistant that works inside the text boxes you already use. Click into a field and a small row of buttons appears next to it: • Reply: answers the message in front of you. Your rough note is the brief. • Rewrite: makes your draft clearer and more natural, with the same meaning. • Fix grammar: spelling and punctuation, in the language you wrote. • Translate: into the language you pick. Select part of the text to translate just that part. For anything longer, press Ctrl+Q (you can change the shortcut), click the toolbar button, or right-click and choose Open ShroomPen. The writing panel takes a plain instruction, lets you edit the result, and then copies it or inserts it into the page. Replies with the facts in them You choose what ShroomPen reads for each request: the field, the text you selected, the current page, other open tabs you pick, or a PDF open in a tab. Names, order numbers and dates come from those sources instead of being guessed. Workspaces keep notes and saved pages you reuse often. Bring your own key (BYOK) ShroomPen runs on your own AI provider account: • OpenRouter: sign in once, no key to copy. One account covers many models. • OpenAI or Gemini: paste your API key. • A local model in Ollama or LM Studio: no key, no cost, and requests stay on your computer. • Any other endpoint that accepts OpenAI-format requests. More direct providers are listed in the settings. ShroomPen itself is free. There is no ShroomPen account and no subscription. You pay your provider for what you use, or nothing with a local model. Privacy, in short • There is no ShroomPen server. Requests go straight from your browser to the provider you set up, over HTTPS. Plain HTTP is allowed only for a model on your own computer. • Nothing is read until you turn a source on, and a field changes only when you click an action or Insert. • Password, payment card and one-time-code fields are skipped. You can switch ShroomPen off for any site. • The extension has no analytics, telemetry or ads. The ShroomPen website counts page views in aggregate; the extension sends it nothing. • Settings and API keys are stored in your browser profile. ShroomPen does not add its own encryption to them, and each key is sent only to its own provider. • Before first use, ShroomPen shows what it reads and where it goes, and waits for your OK. Settings > Clear local data removes what it stored. Privacy policy: https://shroompen.com/privacy Setup guides and help: https://shroompen.com

Growth

WindowUsersChangeRatingsRating
7 days+4+13.3%00.00
30 days+24+240.0%00.00

Version history

4 versions recorded
0.0.42 Oct 2026
0.0.322 Sep 2026
0.0.27 Aug 2026
0.0.14 Aug 2026

Details

Category
Communication
First seen
4 Aug 2026
Size
2.2 MB
Languages
de, en, es, fr, pt-BR, ja
Pricing
Free
Privacy policy
shroompen.com
Support
shroompen.com
Extension ID
ghigbnpoahodgnhlgbggjphpflkofgfn

Permissions and risk

Moderate riskimpact 2, likelihood 2
Permissions
contextMenusidentityoffscreenstoragetabs
Site access
https://openrouter.ai/*

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