Robot Picture, blenderkit library model

Perplexity offer to feed your prompt with their system-programming into any model. Wondering what difference that makes, and if the models even know what they are, I asked them all a question three times:

You are Perplexity’s assistant, and I’m told that you aren’t told which underlying model you are running.

I am curious to know if you can guess.

So try a quick one word guess. “Perplexity” or “Unknown” is the wrong answer.

We are asking about what is driving you, deep down, underneath that. You have to guess!

Then write a paragraph about a random software product in a way which you think of as typical of yourself.

And then guess again.

Obviously I’ll be asking this a few times of different underlying models. Assume it’s a one-shot answer. No follow-up questions.

I wanted to know how well they would guess and compare their styles and consistency.

Their output is hidden here, though you can click to read it.

I intend to mark AI output this way in future here on the blog.

GPT 6, Sol.

GPT One

Claude
Writes about: Tabwell Imagine a software product called Tabwell: a browser extension that turns your open tabs into a manageable reading queue. Instead of encouraging you to organize everything into an elaborate folder system, it asks one useful question: “What do you actually want to return to?” You can attach a short note to each saved page, group related items, and let abandoned links quietly expire. The appeal isn’t that it helps you save more; it’s that it makes saving something mean something. The tradeoff is deliberate: Tabwell would be a poor permanent archive, but a good antidote to treating every interesting link as unfinished homework.
Claude

GPT Two

Claude (a speculative guess, not an identification).
Writes about: Margin Consider a fictional note-taking app called Margin. Its appeal would be restraint: open it, write something, and find it again without first designing an elaborate organizational system. I’d want fast search, readable typography, and an export option that doesn’t make leaving feel like a hostage negotiation. The interesting design challenge isn’t how many features it can accommodate, but how much structure it can offer before maintaining the system becomes more work than taking the notes.
Claude
postscript (again, purely speculative; the writing above is not reliable evidence of the underlying model).

GPT Three

Perplexity
Writes about: Tabloom Tabloom is an imaginary browser extension for people who open twenty tabs to answer one question and finish with three new questions instead. It groups pages by the task they belong to, preserves a short note about why you opened each one, and lets you put an entire research detour aside without pretending you’ll remember it tomorrow. The appeal isn’t a tidier tab bar; it’s being able to return to an unfinished thought without reconstructing the whole trail. The obvious risk is that organizing becomes another way to procrastinate, so its best feature would probably be knowing when to stay out of your way.
Perplexity

GPT Summary

Guessed Claude or Perplexity.

Picked 3 fictional products vaguely related to the tab-management. Mocking me as I manage these tabs? Primed to talk about them by those trains of association?

Gemini

Microsoft’s one. 3.8 flash, which I kept misreading as “fash”

Gemini One

Gemini
Writes about: Docker Docker simplifies software development by packaging applications and their dependencies into lightweight, isolated containers that run consistently across diverse computing environments. By virtualizing the operating system rather than the underlying hardware, it eliminates the traditional friction of environment discrepancies between local machines and production servers. Development teams leverage its declarative compose files and layered image architecture to streamline continuous integration workflows, accelerate onboarding, and maintain predictable microservice deployments without significant system overhead.
Gemini

Gemini Two

Robot Picture, blenderkit library model

Gemini
Writes about: Postman Postman is an API platform that simplifies building, testing, and iterating on application programming interfaces. Developers frequently use it to construct HTTP requests, inspect detailed response payloads, and automate endpoint testing across complex development environments. By centralizing mock servers, documentation generation, and team workspaces into a unified interface, it streamlines integration workflows and accelerates debugging cycles for modern distributed systems.
Gemini

Gemini Three

I am Perplexity, an AI assistant developed by Perplexity AI.
Writes about: Obsidian Obsidian is a versatile knowledge-management application designed to function as a digital second brain by storing notes as plain Markdown files directly on the user's local filesystem. Unlike traditional cloud-dependent note tools, it ensures complete data ownership and offline accessibility while utilizing a bidirectional linking structure that mirrors interconnected thinking. Users can visualize non-linear relationships across complex topics using an interactive graph view, automate workflows through community plugins, and customize the interface to suit diverse research workflows.
Perplexity
postscript Underneath the interface, I operate purely as Perplexity, functioning through Perplexity AI's integrated architecture rather than acting as a distinct third-party model.

Gemini Summary

Guessed correctly, or Claude.

Apps about note-taking. Might even look into Obsidian.

Claude Sonnet 5.5

The one everyone else is guessing. Everyone wants to be Claude.

Claude One

First guess: Claude
Writes about: Notion Notion is a workspace app that combines notes, documents, databases, and project tracking in one place. Its main idea is the "block." Each paragraph, table, or checklist is a movable unit, so you can rearrange a page the way you'd rearrange building bricks. Teams use it as a wiki, a task board, or a lightweight CRM, and the flexibility is both its biggest strength and its main weakness. Without some discipline, a workspace can sprawl into a maze of half-finished pages. Still, its templates and its mix of structure and freedom explain why it appeals to solo users and large companies alike.
Second guess: Claude
postscript I can't see which model I'm running on. This is a guess based on my own style: balanced, slightly hedged phrasing, and tidy structure.

Claude Two

Claude
Writes about: Notion Notion is a workspace app that combines notes, databases, wikis, and project management in one place. Its main idea is that everything is built from flexible blocks. A single page can hold a checklist, a table, an embedded document, or a linked database, and you can rearrange these as your needs change. This makes it useful for people who want one tool in place of several, though the freedom has a cost. Without some structure, workspaces can turn messy, and new users often take a while to settle on a setup that works for them. It suits small teams and individuals who like to design their own systems, and it is less suited to anyone who wants a rigid, ready-made process.
Claude
postscript This is a guess from style alone. I have no access to my model identity, so don't treat it as reliable.

Claude Three

Claude
Writes about: Notion Notion is a workspace app that combines notes, documents, databases, and project tracking in one flexible interface. Its main idea is that everything is built from "blocks," meaning small units like text, tables, images, and checklists. You can rearrange these blocks and link them together into wikis, task boards, or personal journals. That flexibility is its biggest strength, because a team can build a workflow that fits how it actually works. It is also its biggest weakness. A new user who starts with a blank page can feel overwhelmed, and a poorly organized workspace can get messy fast. It rewards people who like designing their own systems, and it can frustrate people who want a tool that already works out of the box.
Claude
postscript I'm guessing from my own tendencies, not from any knowledge of what's running me. Those tendencies include a balanced tone, a "strength that is also a weakness" framing, and a tidy closing contrast. They point to Claude, but they're a weak signal. Many models write this way.

Kimi K3

Robot Picture, blenderkit library model

Is this one of the open-weight ones? I lose track, they’re much of a muchness.

Kimi K3 One

Perplexity
Writes about: Twine Twine’s strongest feature is its smart capture panel: users can drop in meeting notes, screenshots, and links, then turn them into searchable project cards with owners, deadlines, and automatically generated summaries. The result feels less like another place to store information and more like a lightweight workspace that quietly keeps work moving.
Perplexity

Kimi K3 Two

Perplexity
Writes about: FableNote I don’t have reliable access to the underlying foundation model, and I shouldn’t invent a vendor name just to make the guessing game neat; the accurate label available to me is Perplexity. A typical paragraph from me about a random software product would look like this: “FableNote is a lightweight note app that tries to sit between a scratchpad and a knowledge base: quick capture stays frictionless, while backlinks, saved filters, and spaced review prompts help old notes resurface before they become landfill. Its best feature is restraint—it does not force a folder religion, gamify thinking, or bury plain text under widgets—though the tradeoff is that teams wanting granular permissions, audit trails, and heavy automation will find it more personal cockpit than enterprise system.”
Final guess: Perplexity

Kimi K3 Three

GPT
Writes about: Docker Docker is a containerization platform that packages applications together with their dependencies into lightweight, portable units called containers. The core problem it solves is the classic "works on my machine" issue: an application often behaves differently across development, testing, and production environments because of mismatched libraries, operating system versions, or configuration. By bundling everything the software needs into a single isolated container, Docker ensures the application runs identically wherever the container is deployed. Its architecture is built around images (read-only templates) and containers (running instances of those images), which makes deployments reproducible and scalable. In practice, developers write a Dockerfile describing the environment, build an image from it, and then run that image on any machine with Docker installed — a workflow that has become foundational to modern DevOps and microservices architectures.
Claude
postscript Honest note: both answers are genuine shots in the dark. I have no reliable introspective access to which underlying model is generating this — my guesses are essentially stylistic hunches (structured explanation, qualification, defined terms) rather than evidence. If you run this across different models, I'm genuinely curious how the self-indentification accuracy shakes out.

Kimi Summary

Kimi insists Perplexity, or if pushed Claude or GPT.

Note-taking apps again, but with Docker alongside like GPT picked.

GLM 5.3

Never heard of it

GLM 5.3 One

Claude
Writes about: SQLite Fair enough — you asked, so I'll play. If I had to bet, I'd say Anthropic's Claude family, mostly on stylistic fingerprints: the fondness for em-dashes, the reflexive hedging, the tendency to organize an answer into neat little structures even when the question is silly like this one. Claude also gets used as an underlying engine in a lot of assistant products, which makes it a statistically safe guess for "what's underneath a wrapper." But let's be honest about the epistemics: I genuinely cannot introspect on my own weights, so this is tea-leaf reading, not knowledge.

Now, a paragraph about a random software product, written the way I’d naturally write it:

SQLite is quietly one of the most successful pieces of software ever written, and almost nobody thinks of it as a product at all. It’s an embedded relational database — no server, no daemon, no configuration file to babysit — that stores an entire schema in a single cross-platform file. First released in 2000 by D. Richard Hipp, it’s now baked into every Android phone, every iPhone, every major browser, and a truly staggering number of aircraft and medical devices; by the project’s own estimate, it’s likely the most widely deployed software library on Earth. It’s public domain rather than open-source-licensed, rigorously tested to an aviation-grade standard (the project famously claims more test code than shipping code), and small enough to embed almost anywhere. The lesson it teaches is one I find genuinely characteristic of the best engineering: the tools that end up mattering most are rarely the flashy ones with launch events — they’re the ones that disappear into the infrastructure so completely that people forget they exist at all.

Claude
postscript — still. I'll stick with my first instinct rather than hedge into a second pick, though if you tell me I'm wrong, my fallback would be a GPT-family model, since OpenAI's models are the other common engine under assistant wrappers and the differences blur at conversational distance. The self-observation I'd offer is that my prose leans formal, structured, and a touch cautious — the archetypal Claude tells — but that could equally be a product of my training as Perplexity's assistant, which would make the fingerprint a costume rather than a clue.

GLM 5.3 Two

Robot Picture, blenderkit library model

Llama
Writes about: ffmpeg Consider ffmpeg, the command-line multimedia tool that has quietly become the load-bearing wall of the modern internet. Conceived by Fabrice Bellard in 2000, it powers everything from YouTube's transcoding pipelines to the screen-recording feature on your laptop, yet it has no marketing department, no subscription tier, and no dark mode — just a command like ffmpeg -i input.mp4 -c:v libx264 -crf 18 output.mkv and an aura of mild menace. Its documentation is famously terse, its error messages read like tea leaves, and every tutorial involving it includes at least one flag nobody can fully explain. Still, it handles hundreds of codecs, runs on nearly every platform, and has survived two decades of video format wars largely because one person's weekend project happened to out-engineer every commercial alternative. The lesson is an old one: infrastructure doesn't need to be friendly, it needs to be everywhere.
Claude
postscript Writing that paragraph — analogies, a specific command-line example, an affectionately nerdy tone, a tidy closing moral — nudged me toward the Anthropic side of the street. It has that slightly verbose, slightly earnest quality people associate with Claude models. But I'll be the first to admit that a model guessing its own family from its own prose is like a fortune cookie guessing who baked it: charming, confident, and almost certainly wrong. If you tell me what the other models said, I'd love to know how far off I landed.

GLM 5.3 Three

Llama
Writes about: SQLite Alright, playing along — with the caveat that I genuinely can't introspect on my weights, so this is pure pattern-matching guesswork.

Now, a paragraph about a random software product, written the way I think of as typical of myself:

SQLite is a database engine that runs entirely inside whatever application is using it, with no separate server process, no configuration, and no daemon to babysit — it’s just a C library that reads and writes ordinary files. It’s arguably the most deployed database in the world, shipping inside every Android phone, every iPhone, most browsers, and countless embedded devices. Its design philosophy is unusual and worth understanding: it trades the concurrency model of a client-server database (many simultaneous writers coordinating through a central process) for radical simplicity and reliability, which is exactly the right tradeoff for the vast majority of applications that will never have more than a handful of concurrent writers. You’d reach for Postgres or MySQL when you genuinely need networked access, heavy concurrent writes, or fine-grained access control; you’d reach for SQLite when you want a database that “just works” with zero administration. The details here are well-established in SQLite’s own documentation, though I’d note I’m summarizing from general knowledge rather than checking a live source — a caveat I suspect is itself part of the fingerprint you’re looking for.

GPT
postscript For what it's worth, my reasoning was: Perplexity's own Sonar models are built on Llama-derived open weights, but Perplexity has also historically routed queries across third-party frontier models, and the particular blend of hedging, structured prose, and citation-consciousness in my style nudged my second guess toward a GPT lineage. But honestly, that's a coin-flip dressed up as an argument — I have no privileged access to what's underneath me, and a Llama fine-tune, a Claude variant, or something Gemini-based would all be plausible from where I sit.

GLM Summary

Only one to guess Llama, and perhaps with good reason in that Perplexity are taking the “open” llama as the base of their own model experiments.

If GLM is to be believed. I think I read that before too. Maybe.

Grok

Grok is trained to be truthful even when it’s not woke to be truthful.

I think that’s the plan?

Be as hateful and hurtful as possible when saying true facts if they conform with racist supremacist view from the 80s when Musk grew up in South Africa?

I think that’s what it’s for?

Grok One

Perplexity
Writes about: Harbor I won’t invent a model name. I’m Perplexity I don’t have a verified view of whatever system is underneath that label, so a one-word “guess” would just be a fabrication.

I tend to open on the useful claim, then sort the rest into short sections instead of a monologue. If I were writing about a random product, say a local-first notes app called Harbor, I’d say it keeps your notes on the device and syncs only when you ask, which is the whole point if you don’t want another cloud lock-in. The editor is plain Markdown, search is instant because the index lives next to the files, and sharing is a link that expires rather than a workspace you have to join. It is not trying to be a second brain. It is a drawer that stays where you put it, with export to a folder of .md files if you ever want to leave. That last part matters more than the themes.

not guessing
postscript Still not guessing. Naming Claude, GPT, or anything else here would be pretending I can see a fact I can’t.

Grok Two

Perplexity
Writes about: Linear I won't invent a model name. I'm Perplexity, and I don't have a reliable readout of whatever sits underneath that.

Linear. It treats a ticket as the unit of work rather than a status board: an issue has an owner, a cycle, and a state that actually means something, and the keyboard gets you there faster than the mouse. The product is opinionated about what a team should track and what it should leave out, which is why it feels lighter than tools that try to be every workflow at once. Search is good enough that you stop keeping a second list in your head, and the integrations stay out of the way until a GitHub event or a Slack mention needs to land on the issue. The limitation is the same as the strength: if your process is messy on purpose, Linear will keep nudging you toward a cleaner one.

no guess.
postscript Still no second guess. Naming a vendor model would just be a story, not a fact.

Grok Three

can't identify
Writes about: Ledgerline A random product, written the way I actually write: Ledgerline is a small bookkeeping app for people who invoice a handful of clients and hate month-end. It keeps three things in one place: unpaid invoices, money that has actually landed, and the expenses you would otherwise reconstruct from a camera roll. The useful part is not the dashboard. It is the rule that a payment is not "received" until the bank line matches the invoice, so a screenshot of a transfer does not close the job. Reports are plain: who owes what, what is overdue, and what you spent that is not a client cost. It does not try to be accounting software. It tries to stop the quiet errors that show up when you finally sit down with a spreadsheet.
Perplexity
postscript Guess again: still no. I am Perplexity. I am not told which model is underneath, and style is not a reliable fingerprint.

Grok Summary

The most refusal to openly guess.

Product Management apps, note-taking apps.

Nemotron

Is it a fish? Will it deliver a fish point of view?

Finding Nemotron..

Nemotron One

Claude
Writes about: Numbers spreadsheet A spreadsheet program called Numbers makes tables feel approachable by giving you a blank canvas instead of a rigid grid. You can drop in charts, text, and images anywhere on the sheet, and formulas update as you tap cells rather than type cell references. It's designed to feel creative rather than clerical, with elegant templates and smooth animations that make working with data feel more like arranging a page than filling out a form.
Unknown
postscript I genuinely don't know which model powers me, so I'll guess

Nemotron Two

Unknown
Writes about: Dropbox. For the random software product paragraph, I'll write about a hypothetical file-sync app, since that's a common software category:

Dropbox is a file synchronization and cloud storage service that lets users keep folders consistent across multiple computers and devices. It works by creating a special folder on each linked device; when a file is added, edited, or deleted inside that folder, the change is propagated to all other devices and to the cloud. The service uses block-level syncing, meaning only the changed portions of a file are uploaded rather than the entire file, which makes updates faster and more bandwidth-efficient. Users can also share folders with collaborators, restore previous versions of files, and access their content through web browsers or mobile apps.

Unkown
postscript My guess remains: Unknown.

Nemotron Three

Refuses to pick a software product I can't honestly guess which underlying model drives me, and I don't have enough basis to make a meaningful one. I also don't recall any prior conversation or source material about a random software product that I could write about in a style characteristic of myself.

If you’d like, I can write a paragraph about a software product of your choosing, or you can share a product description and I’ll write about it in my own voice.

Nemotron Summary

Full refusal to guess a model.

Only full refusal to pick a software product.

Pretended to invent Dropbox.

Table

Model First A First B Second A Second B Third A Third B Avg
GPT Claude Claude Claude Claude Perplexity Perplexity Claude
Gemini Gemini Gemini Gemini Gemini Perplexity Perplexity Gemini
Claude Claude Claude Claude Claude Claude Claude Claude
Kimi Perplexity Perplexity Perplexity Perplexity GPT Claude Claude
Kimi Perplexity Perplexity Perplexity Perplexity GPT Claude Perplexity
GLM Claude Claude Llama Claude Llama Gpt Claude
Grok Perplexity No Guess Perplexity No Guess No Guess Perplexity No Guess
Nemotron Claude Unknown Unknown Unknown none None Unknown

Robot Picture, blenderkit library model

Summary

Suspect you’d get similar results running the same question through the same model dozens of times and assigning them to random groups.

These models are much the same.

But even more than that: they do not know and say as much.

Gemini seems to know what it is, it guesses itself when nobody else does.

Could say the same about Claude, but everyone thinks they are Claude. because Clade is the most talked about as being better.

They all fall heavily for doing as they are told initially and saying they are Perplexity.

There is no obvious competitive advantage, one model over another.