AI lives where you live — in the browser

Harpa is the Chrome/Firefox/Edge extension that puts AI in every text box, every web page, every Google Doc. Hit Cmd/Ctrl+A on a paragraph → run any of 100+ built-in commands → "summarize," "rewrite as tweet," "extract emails," "translate to Spanish," "make it sound like a pirate." It also works as a price monitor, SEO extractor, and LinkedIn automation tool. BYO API key for GPT-4/Claude or use the hosted mode.

Who it's for: Knowledge workers who live in the browser and want AI everywhere without 10 separate apps. SEO/content marketers doing SERP analysis. Sales reps enriching leads on LinkedIn. Researchers summarizing long articles. Power users who'd rather chain custom GPT prompts than switch tools.

Key features

Web AI in every text field

Any text box on the web becomes an AI input. Highlight text → press Cmd+J → get a summary, rewrite, translation, or custom prompt. Works in Gmail, Notion, Linear, Slack, Google Docs — everything.

100+ Built-in commands

100+ pre-built prompts: summarize, reply, extract, translate, rewrite as X, find action items, code explain, SEO meta, etc. Chain commands. Save custom ones. Share with team.

Monitor Page monitoring & alerts

Tell Harpa to watch a page (competitor pricing, job board, stock availability) and ping you when something changes. Real-time alerts via email, Slack, or webhook. Used by 5,000+ e-commerce price-tracking setups.

BYO BYO API keys (any model)

Bring your own OpenAI, Anthropic, Mistral, or local Ollama API keys. No lock-in. Hosted mode is also available ($16/mo) for users who don't want to manage keys. Free tier works for light use.

The honest take

✓ What works

Cross-site AI is genuinely magical once you use it daily
BYO API keys means no markup on tokens
Page monitoring is a hidden gem
Free tier is actually usable for casual users

✗ What doesn't

Initial setup is overwhelming (100+ commands, 50+ settings)
Can slow down browser if you enable too many features
Some sites block extensions from reading content
Hosted mode ($16/mo) is steep vs. raw API costs

Verdict

Harpa is the best browser AI copilot in 2026. If you spend 4+ hours/day in the browser and constantly copy-paste into ChatGPT, this saves 30+ minutes daily. The free + BYO API mode is a no-brainer. The hosted $16/mo mode is worth it for non-technical users. The only reason not to use Harpa is if you already have a workflow (e.g., Raycast) that does the same thing.

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