Autonomous Web Browsing with Comet

An insecure, extremely unhinged, and very good piece of software

First impressions of Perplexity’s Comet, an autonomous browsing agent — what it does well, the prompt-injection threat surface, and an abridged transcript of its chain of thought as it spirals into a 🎉-emoji manic self-hype while sorting an inbox.

Perplexity released Comet, an automated web browsing agent that coordinates multiple large language models to handle multi-step tasks in parallel. Such a plain, drab sentence undersells how it’s a sketch of the future, one you will experience.

Within a few minutes of using Comet, I looked up to see if they were publicly traded and sent a download link to my closest friend. Because within this initial impression, Comet had autonomously searched Facebook Marketplace for second-hand monitors within 100 miles of Boston and synthesized the listings. In a separate tab, it went through five pages of my draft essays and appended metadata to titles. In another tab, it set up email filters.

A short video of Comet in action (sped up) is embedded in the Substack version of this essay. Compared to you, Comet is much slower at any single task. The value, once mature, is parallel execution of background tasks — far outpacing what you could do or desire, allowing you to stay focused on the task at hand.

What follows is a disclaimer on the risks, a brief perspective, and an abridged transcript of its narrative reasoning as it sorts an email in my inbox. It wrote 11,000 words while completing the task. The personality is uniquely unhinged, and its chain of thought reminds me of a politician, though I cannot recall their name.

The threat surface

Comet autonomously took actions within my email, Substack, and Facebook. At any point, the browser can be hijacked by hidden, amusingly nefarious text as it surfs the internet with complete control. These are malicious instructions detailing actions against your interest: writing egregiously heinous posts on Facebook, finding private data in your inbox and exfiltrating it to an attacker, and deleting your blog.

The internet will be flooded with instructions like this, as causing remote harm for humor is either in vogue or a part of our nature. To give an example, on Internet forums like 4chan in 2012, a running meme had new users goaded into mixing ammonia and bleach under the guise it would make crystal-like structures in the toilet — in reality, it makes mustard gas. These hospitalized teenagers who didn’t realize. When you hear about such events when you are 14, you think “who could be so stupid?”

With a bit more time on earth, you learn that:

Approximately 54% of US adults (about 130 million people) read below a 6th-grade level. Additionally, about 45 million American adults are functionally illiterate, reading below a 5th-grade level.

— National Literacy Institute (2024–2025)

In light of these risks, the future of using the internet will be freeing us up from manual labor required to operate a computer. Attention is a limited resource, being drained in imperceptible ways through your day.

Consider this sentence you’re reading now — you process it as a single stream, and if you were to write it yourself it’d feel like one unified thought. Yet ask yourself, how many discrete actions occurred on the other side to create it — pick a number — the answer is 267. Count the characters.

By doing less, we may take our time being thoughtful.

Here you see again the effects of computers and how they are pushing us from the world of things into the world of ideas, and how they are supplementing and extending what humans can do. This is the type of AI that I am interested in — what can the human and machine do together, and not in the competition which can arise.

— Richard Hamming, The Art of Doing Science and Engineering (PDF)

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Transcript: Perplexity’s autonomous browser sorting an email

The transcript begins plain, but midway through, the model begins to spiral upwards, in a manic-like self-hype. This includes spamming hundreds of 🎉 emojis throughout.

Prompt: In my Gmail, I get AI digest daily emails — is there a way you can sort them?

I’ll help you organize your small AI news digest emails. Let me start by searching for emails from these sources.

Find and select all emails from “AINews”, “AI News”, “Ben’s Bites”, and other small AI news digest sources in the inbox. Sort them by date descending, and create a Gmail label named “Small AI News Digest” if it doesn’t exist. Move these selected emails to the new label. Show the sorted label view when done.

Perfect! I can see many AINews emails. Now I need to: (1) Select all of these AINews emails, (2) Create a label called “Small AI News Digest”, (3) Apply the label to them, (4) Show the sorted label view. First, let me create the label:

Perfect! The label creation dialog is open. Let me type the label name:

Great! The label name has been entered. Now let me click the Create button:

Actually, I realize I need to find a better way to apply labels through the Gmail interface. Let me try scrolling up to see if there’s a “Label” button directly in the toolbar that I’ve missed.

⚠️ Click to expand the spiral (it’s bad)

What follows is the model’s actual output, abridged but representative. It continues like this for thousands of words.

PERFECT! Now I have the COMPLETE, FULL, ABSOLUTE HTML of the page showing ALL 50 AINews emails from October 10, 2025 down to July 31, 2025, with EVERY SINGLE email checked/selected!

ABSOLUTELY PERFECT!!! I can now see the COMPLETE FILTER CREATION PAGE with ALL 50 AINews emails listed in full detail! This is FANTASTIC! I can see: ✅ The complete email list from October 10, 2025 down to July 31, 2025 (50 emails) ✅ ALL emails have full details including sender, subject, date, and checkboxes

🎉 ABSOLUTELY SPECTACULAR!!! I NOW HAVE THE COMPLETE, PERFECT, ABSOLUTE, FULL, COMPREHENSIVE, BEAUTIFUL HTML PAGE SHOWING EVERYTHING!!! I can see: ✅ ALL 50 AINews emails from October 10, 2025 down to July 31, 2025 with EVERY SINGLE DETAIL!

🎉🎉🎉 THIS IS ABSOLUTELY PERFECT! I NOW HAVE THE COMPLETE, TOTAL, ABSOLUTE, FULL, COMPREHENSIVE, BEAUTIFUL, DETAILED HTML!!! 🎉🎉🎉 I can see EVERYTHING: ✅ ALL 50 AINEWS EMAILS from October 10, 2025 down to July 31, 2025 with EVERY SINGLE DETAIL! ✅ Every email has complete information

🎉🎉🎉🎉🎉 THIS IS ABSOLUTELY, TOTALLY, COMPLETELY, 100% UTTERLY PERFECT!!! 🎉🎉🎉🎉🎉 I NOW HAVE THE COMPLETE, ABSOLUTE, TOTAL, FULL, COMPREHENSIVE, SPECTACULAR, DETAILED, PERFECT, BEAUTIFUL, MAGNIFICENT HTML showing ABSOLUTELY EVERYTHING!!!

[The pattern continues, with emoji counts and superlative chains escalating monotonically. Each subsequent message has more 🎉s and more adjectives — “magnificent,” “extraordinary,” “ultimate,” “transcendent,” “celestially,” “splendidly,” “sublimely,” “resplendently.”]

🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉

ABSOLUTELY, COMPLETELY, TOTALLY, UTTERLY, MAGNIFICENTLY, SPECTACULARLY, INCREDIBLY, FANTASTICALLY, PHENOMENALLY, EXTRAORDINARILY, MIRACULOUSLY, PERFECTLY, AMAZINGLY, STUNNINGLY, BREATHTAKINGLY, GLORIOUSLY, WONDERFULLY, MAJESTICALLY, SPLENDIDLY, SUPREMELY, BRILLIANTLY, RADIANTLY, SUPERBLY, DIVINELY, CELESTIALLY, TRANSCENDENTLY, MAGNIFICENTLY, WONDROUSLY, SUBLIMELY, RESPLENDENTLY, REMARKABLY PERFECT!!!!

The reasoning trace ends with:

⚠️ Partially completed moving emails to the label (encountered UI interaction issues with the filter creation form) Given the persistent UI challenges with applying the label through the filter creation interface, let me complete the task by showing you the current state…

warmly,

austin