Early concept · in development

Who made this — and has it changed since?

Assayer is an independent assay office for AI-era content. Creators and models sign at the source; anyone downstream gets one calibrated origin-and-integrity verdict — fused from every signal that survives real editing, and honest enough to answer “Inconclusive” before it ever falsely accuses.

verdict · origin & integritysample
0.94
Verified origin
Lightly altered since signing — benign.
Content credentialintact
Generation watermarkpartial
Semantic fingerprintmatch · graded
File metadatastripped
VerifiedLikelyInconclusive
The honest premise

Watermarks wash out. We built for that.

An AI-text watermark is a statistical bias in token choice, not hidden data. It survives a copy-paste — and little else. So Assayer never leans on a single mark; it weighs every signal by how much of it could have survived the edits it actually finds.

copy-paste, re-export
Preserved
Token order is unchanged, so the statistical signature and a bound credential both ride along.
translation, synonym swaps
Degraded
Pivot-translation and edits break the token seeds; watermark confidence falls, the credential holds.
paraphrase via another model
Gone
A different, unkeyed model resamples the text and wipes the mark entirely. No mark can be trusted to survive this.
How a verdict is made

Sign at the source. Fuse what survives. Abstain before accusing.

01

Sign at the source

At creation, a maker or model mints a portable content credential that binds who, when, and which tool to the artifact’s content hash. Signing is client-side — the key never leaves the creator.

02

Gather what survived

Downstream, Assayer collects whatever remains — the credential, any surviving watermark, a semantic fingerprint, metadata — and recomputes the hash to see what changed since signing.

03

Grade, then fuse

Each signal is weighted by how reliable it is and how much could have survived the edits detected, then fused into one calibrated band — Verified, Likely, or Inconclusive — never a lone number.

04

Abstain before accusing

Below the confidence floor, or when signals conflict, the verdict is a calm grey “Inconclusive” — logged, reproducible, and inside an intended false-accusation budget. We go grey, not red.

Sign at the source

A hallmark, stamped at creation.

The strongest signal doesn’t depend on a fragile mark surviving later edits — it’s a cryptographic credential minted when the content is made, bound to its hash and registered to a maker’s mark. One SDK call, client-side, and the chain of custody begins.

assayer · mint credential
PDF
q4-forecast.pdf
actorstudio.example
toolmodel-a
methodAI-assisted
minted2026-10-30 11:04Z
content-hashsha256:9f2c…a71b
Registered to the Assayer Register
# client-side, key never leaves you
assayer.sign(artifact, key)
Calibration & abstention

A confidence that means what it says.

A stated “90%” should be right about nine times in ten — so Assayer is designed to measure and publish its own calibration, and to abstain below a floor rather than invent certainty. The costliest error in this field is a false accusation, so the UI has no “guilty” state — only confidence, and honest grey.

calibration & abstain · illustrative
stated confidence → abstain zone
measured accuracy tracks stated confidence; below the floor → abstain
False-accusation budget
≤ 1 wrong accusation / 1,000 verdicts
illustrative example · example consumption 0.3
Inconclusive

When evidence is thin or conflicting, Assayer goes grey, not red. “We can’t be sure” is a first-class, logged answer — never an accusation.

All figures illustrative at concept stage — nothing here is a measured result.
A signed newsroom PDF; its credential resolves and the recomputed hash matches exactly.
Origin verified · unaltered
Verified
A product photo whose C2PA manifest was stripped on re-upload, but whose pixels still match a registered original.
Likely from the claimed source
Likely · manifest missing
An essay paraphrased through a different, unkeyed model before submission — no credential attached.
Cannot attribute
Inconclusive · abstain
Chain of custody

Settle disputes with history, not a snap judgement.

Every verdict writes to a reproducible chain of custody — each hop annotated with which signals survived it, and exactly where integrity last provably held. Anyone can re-run the check.

Minted
11:04Z
credential stamped
Copied to CMS
11:20Z
all signals intact
Translated EN→FI→EN
11:38Z
watermark lost · credential intact · fingerprint graded
Light edit
11:52Z
hash diverges · flagged benign
Now
verify
one calibrated verdict
✓ provably intact until 11:52Zreproducible — re-run this check
The Register & verify API

The network is the moat.

A portable, open content-credential standard plus an issuer registry of makers’ marks — worth more with every creator that signs and every surface that verifies. Institutions wire one endpoint into an LMS, CMS, newsroom or intake system and verify at scale.

Issuer register
studio.exampleactive
press.exampleactive
model-aactive
lab.examplerotated
POST /v1/verify   { origin: 'verified', integrity: 'benign-edit', confidence: 0.94, abstained: false }
illustrative — no participants implied
Why it’s defensible

The mark is a commodity. The calibrated verdict and the Register are not.

Any single watermark can be stripped or paraphrased away, so Assayer doesn’t sell one. It owns two things that compound instead: a survival-weighted fusion engine that turns whatever evidence is left into one honest, calibrated verdict — modelling the asymmetric-key reality, where a key-holder’s credential is near-certain and a keyless guess is heavily discounted — and the Register, a portable credential network that grows more valuable with every maker who signs. The defensible part is the verdict you can trust and the network others plug into, not the model and not the mark.

Questions

The honest answers.

Isn’t a watermark enough?

No — and pretending otherwise is the mistake. An AI-text watermark is a statistical bias in token choice, and a single paraphrase through an unkeyed model wipes it completely; file and metadata marks strip even more easily. Assayer treats marks as disposable corroborators and leans on the cryptographic credential and the Register, which survive copy-paste, re-export and translation. The moat is the calibrated verdict plus the network, not the mark.

Could Assayer falsely accuse someone of using AI?

The whole design resists it. When evidence is thin or conflicting, Assayer returns a calm grey “Inconclusive” instead of an alarm-red accusation, and it is built around an intended, independently auditable false-accusation budget. We would rather say “we can’t be sure” than risk ruining a student or author — abstaining is the feature, not a failure. The UI has no “guilty” state, only confidence and honest abstention.

Do you claim to detect every AI-generated text, or which model made it?

No. We make no claim of an unbreakable watermark or perfect detection. A specific tool is named only when a credential declares it; without a credential or key, and after a clean unkeyed paraphrase, there may be nothing left to attribute — so Assayer reports a calibrated AI-range-vs-human-range likelihood, or abstains, and never pins a specific model on unsigned text. Honesty about the ceiling is what makes the verdicts you do get trustworthy.

Is this a walled garden, or does it work with open standards?

It builds on open, C2PA-style content credentials rather than a proprietary silo, and the Register is portable so issued credentials resolve anywhere. What Assayer adds on top is the survival-weighted fusion engine and the issuer network — the calibrated verdict and the compounding coverage — not another standard to be locked into.

Does verifying content expose it, or its author?

Signing is client-side and binds to a content hash, not the content itself, so the private artifact and the secret key never leave the creator. Verification is designed to be privacy-respecting — resolving a credential and grading signals without hoarding the underlying content — because a provenance layer that leaked what it checked would defeat its own purpose.

We’re building Assayer now

Assay the origin. Abstain before you accuse.

Assayer is an early concept from The Adjacent Possible. We’re building the survival-weighted fusion engine and the credential Register, and we’d like to talk to newsrooms, universities, courts, and enterprises who need provenance they can defend — and who refuse to falsely accuse.

Or write to [email protected]

Concept stage · no customers, revenue or audits yet · every figure on this page is an illustrative example, never a measured result.