BitdepthIndependent grades for inference endpoints
About Bitdepth

We check whether AI providers serve the model they say they do.

Every night, Bitdepth asks the same questions to every company hosting a popular AI model, grades the answers, and writes down what came back. No jargon needed. This page explains it from the ground up.

Five minute read. Skip to the glossary if a word trips you up.

The short version

Think of thirty bakeries.

They all sell "grandma's chocolate cake" from the same recipe. Same name on every sign.

Some quietly use less chocolate. They charge the same. From the outside, you can't tell.

Bitdepth buys a slice from every bakery, every night, and writes down which ones still taste like the recipe.

Tastes like the recipeSomething changed

Illustration only. Not real results.

Now swap the cake for AI

One model name. Many companies serving it. No one checking.

Some AI models are open: anyone can download the files and run them. DeepSeek, Llama and gpt-oss are examples. So when an app asks for "DeepSeek," the request can land at any of dozens of hosting companies. Each one says it is serving the same model. They don't all behave the same.

Same name, many hosts

One September 2026 analysis found a single model served by 33 providers, priced up to 11 times apart.

Labels are self-reported

Providers describe their own setup. Some run a compressed, cheaper version. Nobody outside checks the label.

Bad answers look fine

A cut-off or worse answer still comes back as "success." Users notice before anyone measures it.

The wrong party gets blamed

People blame the app they pay, not the host they never picked. Contracts promise speed and uptime, never the model.

Source for the 33-provider figure: moksh on dev.to, Sept 2026.

How a request travels

You ask. Someone you never chose answers.

1 · Lab
Builds the model

Publishes the open files. The "recipe."

2 · Providers
Host it on their GPUs

Dozens of companies. The "bakeries."

3 · Router or gateway
Picks a host for you

Usually on price and speed. Not on taste.

4 · You
Pay per token

You see the answer. Not who served it.

Bitdepth sits here.Between the hosts and the people paying them, checking every night what each host actually sends back.
What happens every night

A mystery shopper for AI.

1

Ask everyone the same questions

A fixed set of prompts goes to every host serving a model, through the same door any customer uses.

2

Grade with code

Did it get the checkable answers right? Does it agree with itself when asked twice? Did it change since last week?

3

Write it down, dated

Each host gets a dated record. The method is public, so anyone can rerun it and get the same grade.

What we say

What each host returned, compared to the reference and to itself.

What we don't say

Why it differs. We measure behavior, not motives. The cause is the provider's to explain.

The name

Why "Bitdepth"?

An AI model is billions of numbers. Bit depth is how much detail each number keeps.

Fewer bits makes a model cheaper to run, and a little blurrier. Like saving a photo as a smaller file. Usually fine. Sometimes it isn't. Hosts rarely say which they used.

Bar length is detail kept per number. Illustration only. More on this in fp8 vs fp4 vs bf16.

Glossary in plain words

The words you'll see on this site.

Inference
Asking a trained AI a question and getting an answer back.
It is what everyone pays for.
Token
A piece of a word. AI reads and writes in tokens.
Prices are quoted per million tokens.
Open-weight model
An AI whose files anyone can download and run. DeepSeek, Llama, gpt-oss.
Many hosts, one name. That is the whole issue.
Provider
A company that runs a model on its own computers and sells access.
The bakery in the story.
Endpoint
One provider's version of one model, at one web address.
The thing Bitdepth grades.
Router
A marketplace that sends your request to one of many providers.
It picks on price and speed, mostly.
Gateway
Software a company puts in front of all its AI calls to manage them.
Another place a host gets chosen for you.
Quantization
Storing a model's numbers with less detail so it runs cheaper.
Cheaper, sometimes worse, rarely disclosed.
BF16, FP8, FP4
16, 8 or 4 bits per number. More bits, more detail.
The labels hosts declare and nobody checks.
Self-agreement
Ask the same question twice. Does the host give the same answer?
Tells normal randomness apart from a real difference.
Drift
A host answering differently than it did last week.
A nightly check catches it. A one-time test misses it.
Attestation
A dated, signed record that something matched a standard.
Proof you can show someone else.
Fair questions

What people ask first.

Isn't this just a benchmark?

A benchmark tells you which model is smartest, once. Bitdepth tells you whether the host you are using tonight is still serving what it claims. Every night, every host.

How can you tell without seeing their servers?

We don't look inside. We look at the answers. If a host answers differently from the reference, by more than normal randomness, that difference is the finding.

Couldn't a host spot your questions and cheat?

Same risk any mystery shopper faces. Our requests arrive like any customer's. Rotating the question set is how we keep it honest as grades go public.

Who is this for?

Anyone paying for AI answers who needs to know what they got. Apps, gateways, and teams buying AI at scale. The public scorecard is free to read.

Will you name the hosts?

Yes. The public scorecard lists every endpoint by name. Each provider gets a review window before publication, and the method is public.

Is Bitdepth an AI judging other AIs?

No. Today, plain code does the grading: right or wrong against a known answer, same or different from last time.

Seen enough? Go deeper.

Numbers against a stated reference. Not a claim about intent.