Developer documentation
ZadQ binds an x402 selling endpoint to a legally accountable operator: an identity-verified person who answers for it, backed by the issuer's guarantee deposit on the network, issued and checked on an identity network where issuers are admitted and publish status on published terms. On the other side of the payment, an agent operator, the person or organisation that answers for agents that pay, enrols each agent from its account and approves every delegation with a passkey. This documentation describes how the pieces fit together for integrators — the seller side, the buyer side, the agent operator, and the SDK.
The service is live and in early operations: endpoint publication and issuer registration are open.
The integration surfaces
| Surface | Who uses it | What it does |
|---|---|---|
| Seller integration | Operators of x402 selling endpoints | Attach the attestation to HTTP 402 responses |
| Buyer verification | Paying agents and their platforms | Check a seller's attestation locally, free of charge |
| Agent operators | The person or organisation behind agents that pay | Open an account, enrol each agent with a one-time code, approve with your passkey, stop any of them |
| SDK reference | Both sides | The @zadq/x402 package and its copy-in snippets, graceful degradation built in |
| Agent tools and badge | Agents, their harnesses and any page showing a verdict | Two free MCP tools, the badge embed and the verification keys |
Design principles
- Free verification for the buyer. The verification path carries no
charge and no registration requirement.
- Graceful degradation always. Every integration keeps working when no
verdict is available: the badge falls back to the unknown state and the payment flow proceeds unchanged. Nothing in a third-party product depends on reaching ZadQ to function.
- No personal data. Attestation concerns legal entities and endpoint
identifiers. The integration surfaces carry no personal data.
- Open standards. "x402" (HTTP 402 Payment Required) is used
descriptively as the first supported rail; no affiliation is implied.
Where to start
- Operating a selling endpoint? Start with the
- Building a paying agent or a marketplace? Start with
- Answering for agents that pay? The agent operators
page walks the account, the enrolment your runtime claims, the approvals and Stop, Renew and Kill.
- Looking for the code? The SDK reference lists the copy-in
modules and their contracts.
- Wiring an agent, or showing a verdict on a page? The
agent tools page covers the MCP tools, the badge and the verification keys.
The platform
ZadQ is built on the MintID identity network and operated by the CONECTIA group, the network's first implementer, on the same published terms as any issuer: the same admission, the same bond on the network, the same status rules, verifiable by anyone on the network's public record. We disclose this relationship wherever it is relevant.