AffixIO
AffixIO lets AI agents generate and verify zero-knowledge proofs with post-quantum ML-DSA-65 attestations, single-use proof IDs and agent trust checks, without exposing personal data. Hosted MCP with OAuth sign-in via AffixIO Studio.
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Documentation
Check a record.Prove the result.
AffixIO helps your software check a requirement against your records or a connected data source, return a clear yes or no, and keep evidence that another system can verify.
What does that look like?
Illustrative example. No personal data, API request or cryptographic proof is created here.
01 / The record you hold
Is this membership active?
Your membership system holds the account details. The receiving application only needs to know whether the membership is active.
02 / The check
Check the agreed rule
The membership status must be active.
Keep the source record in your system
03 / The result your app uses YES
The membership is active. Your application can continue.
In a real integration
Retain the decision, the rule checked and the proof reference.
An unavailable source is not approval. Keep the action pending or handle it according to your policy. See how a real check works
Your records in.A checkable decision out.
AffixIO fits into the software you already use. Your team chooses the source, sets the requirement and decides what happens next.
- 01
Connect a source
Read an authorised database, file or HTTP API through your integration. Choose the record and field relevant to the check. Supported source patterns - 02
Check a requirement
Evaluate a defined condition, such as an active status or a permission. Use the appropriate proof mode for your application. Choose a proof mode - 03
Use and verify the result
Your software enforces the result. Keep the evidence so another system can check it or your team can review what happened. Understand the evidence
Different questions.The same need for evidence.
Start with one check that matters to your application. The source and policy determine what the result means.
People and eligibility
Does this person meet the requirement?
Check an eligibility condition using records held by your organisation or an authorised provider. Return the relevant outcome instead of copying the full record into another system.
Explore eligibility verification
Accounts and access
Should this application grant access?
Check an active membership, entitlement or permission before opening a restricted workflow. Your application remains responsible for allowing or blocking access.
Explore verification use cases
AI agents and payments
Is the agent allowed to take this action?
Check delegated permission and the proposed action before checkout or a tool call. Agent identity alone does not establish consent to spend or change an account.
An answer you can use.A record you can check.
A result tells your application what the check found. Supporting proof, signatures and audit references help a verifier inspect the evidence later.
You select the capabilities needed for the workflow. A failed check, an unavailable source and a successful verification should remain distinguishable.
Decision
The outcome of the defined check, such as whether the requirement was met.
Proof
Evidence checked under the selected proof mode. UltraHonk and HMAC have different verification assumptions.
Signature
A way to check that signed evidence has not changed and is associated with the signing key.
Audit reference
A reference that helps link the decision to a record of the check. Merkle inclusion can establish that a digest belongs to an audit root.
Check permissionbefore money moves.
Agentic Pay Kit brings permission checks into an agent's purchase workflow. Compare the request with the allowed amount, merchant and user consent before your application continues.
AI agents and proposed personal-superintelligence assistants still need permission for the exact purchase. Superintelligence (SI), also called ASI, is not a grant of authority.
Your payment provider still handles payment authorisation and moves the money.
Need a separate agent identity and proof allowance? Read about BoundProof Agent.
Is this purchase permitted?
Example
Example limit: £75 per purchase
Within policy
The amount, merchant and permission meet the example rules.
Illustration only. No payment, API call or signed proof is created.
One SDK.Start with one check.
Install affixio 2.0.4 in your Node.js application. Connect a configured source, check a condition and generate evidence on your host.
Node.js 20 or later. Keep API keys and source credentials on a trusted host.
npm install affixio
import { AffixSDK, openDataStore } from "affixio";
const sdk = new AffixSDK({
apiKey: process.env.AFFIX_API_KEY
});
const records = openDataStore({
kind: "json", path: "./records.json"
});
const result = await sdk.checkAndProve(records, {
id: "REC-1001",
claimField: "status",
required: "active"
}, { mode: "offline" });
Your source file and a valid licence must be configured. The documentation explains proof modes, verification and sync.
Before you connect it.
Understand what AffixIO does, what your application supplies and where the records stay.
What is AffixIO?
AffixIO is verification software for applications. It helps check a defined requirement against customer-held records or configured external sources and produce evidence of the result. Examples include eligibility, membership status, access permissions and an AI agent's authority to act.
Who is it for?
It is for developers and organisations adding verifiable checks to their own software. People use the resulting service through that application. AffixIO is not a general search engine or a service that can establish every fact about a person.
Can it check external databases and APIs?
Yes. Your integration can connect authorised database lookups, HTTP JSON APIs and supported file exports. You configure source access and the condition to check. An unavailable source should remain an error or unresolved check, not be treated as approval.
Read the source integration guide
Does AffixIO need the full personal record?
Local proof workflows keep the underlying source records in your environment. Remote verification receives the proof material and any public inputs required by the selected workflow. Your team controls those fields and must avoid including unnecessary personal data. External sources receive the information your integration sends to them.
Does a signed result guarantee that something is true?
No. A signature protects the integrity of evidence under a signing key. A proof checks the relation defined by its proof mode and inputs. Neither guarantees that the original source is accurate or that an action is legally permitted in every context.
How does it help with AI agents?
Your application can check whether an agent's proposed action fits a current permission or spending policy before the action occurs. AffixIO supports evidence for that check. Your application enforces the decision; the payment provider still authorises or declines a payment.
Understand agent consent and scope
Which SDK and proof mode should I use?
The npm package is affixio, version 2.0.4, for Node.js 20 or later. UltraHonk zero-knowledge proofs and HMAC envelopes are modes within the package, not separate SDK products. HMAC is not a zero-knowledge proof. Choose the mode appropriate to your verifier and trust requirements.
Can I try it before choosing a paid plan?
Eligible new human Hub account holders can claim one allocation of 100 free proofs. Eligible BoundProof Agents have a separate 150-proof trial. No card is required for these trials; eligibility, expiry and usage terms apply. Check the current offer and pricing before integrating.
Trial details Plans and pricing
What does your application need to check?
Choose a source, a requirement and the action that depends on the answer.
Try your first check.
Eligible new Hub account holders get 100 free proofs. BoundProof Agents have a separate 150-proof trial. No card required.
One allocation per eligible account holder. Trial proofs expire after 30 days. Read the full eligibility terms.