# ValidationRegistry (/programs/validation-registry)



ValidationRegistry is the attestation leg of AgentTrust. PolicyVault reads `ValidationAttestation` accounts when `RequireValidation` is enabled.

## Accounts [#accounts]

| PDA                     | Role                                         |
| ----------------------- | -------------------------------------------- |
| `CapabilityNamespace`   | names a validation capability and schema URI |
| `AttestorProfile`       | records an attestor identity URI             |
| `ValidationRequest`     | opens a request for an agent and capability  |
| `ValidationAttestation` | stores a response, expiry, and revoked flag  |

## Instructions [#instructions]

| Instruction             | Notes                                               |
| ----------------------- | --------------------------------------------------- |
| `register_namespace`    | permissionless, caller computes `SHA256(name_utf8)` |
| `register_attestor`     | self-registration with display URI                  |
| `request_validation`    | subject owner or third party opens a request        |
| `respond_to_validation` | attestor writes the attestation                     |
| `revoke_validation`     | original attestor sets `revoked = true`             |

The program source currently exposes five instructions. The docs reserve the sixth slot for the next attestor-management extension.

## Attestation message [#attestation-message]

The response path uses a domain-separated message:

```txt
AGENTTRUST_ATTEST || subject || capability || payload || expires
```

PolicyVault does not trust arbitrary attestations. `RequireValidation` checks the subject, capability hash, expiry, revoked flag, and allowed attestor list.

## Byte fields consumed by PolicyVault [#byte-fields-consumed-by-policyvault]

| Field           | Offset |
| --------------- | ------ |
| subject asset   | `8`    |
| capability hash | `40`   |
| attestor        | `72`   |
| expires at slot | `208`  |
| revoked flag    | `216`  |

Source: `programs/validation-registry/src/lib.rs`.