---
title: "Evidence pack: definition | KYA glossary"
url: https://knowyouragent.ch/en/knowledge/glossary/evidence-pack
lang: en
updated: 2026-10-12
license: © Innopulse Consulting GmbH
---

# Evidence pack

An evidence pack bundles mandate, decision, receipts, status lists and timestamps into one file whose content is protected against change by a manifest.

The pack allows all cross-references to be checked in one step: whether the decision names the same agent as the mandate, whether the receipt references the decision and whether the [timestamp](https://knowyouragent.ch/en/knowledge/glossary/rfc-3161-timestamp) covers the manifest. Bundled keys count as self-asserted.

## Example

For a dispute, a company exports the evidence pack for one order: mandate, decision, [receipt chain](https://knowyouragent.ch/en/knowledge/glossary/receipt-chain) and timestamp in one file. Any [verifying party](https://knowyouragent.ch/en/knowledge/glossary/verifying-party) can check the pack with KYA and receives the same certificate.

## How it differs

Individual pieces of evidence answer individual questions. An evidence pack bundles everything for one action and also checks the cross-references, such as whether the receipt points to the correct decision and that one to the correct mandate.

## In practice

- Generate the evidence pack directly from the system that keeps mandate, decision and receipts, so no parts have to be assembled by hand.
- Include issuers' public keys for information only; a verifying party should provide them from its own trusted source.
- Verify every pack yourself with KYA before passing it on. If it does not reach the expected level, the certificate shows which part is missing or does not match.

## Role in KYA

KYA verifies an evidence pack in the kya-pack/1 format as a whole: manifest, all parts and their cross-references. Only a complete, time-anchored pack can reach the highest level, KYA-A4.

Related check: [Cryptographic integrity](https://knowyouragent.ch/en/method/checks) (`cryptographic_integrity`). Are signatures, disclosures, hash chains and manifest unchanged?

Evidence packs are exported, for example, by the reference implementation [Mandact](https://mandact.com/en/protocol?utm_source=knowyouragent.ch&utm_medium=referral&utm_campaign=glossar-nachweispaket) (from the operator of KYA); KYA verifies the pack as a whole.

[Verify now: open a matching example](https://knowyouragent.ch/en/verify?beispiel=paket)

## Frequently asked questions

### What is an evidence pack?

A file that bundles all evidence for one action: mandate, decision, receipt chain and timestamp, with a manifest covering all parts.

### What is an evidence pack for?

For audits and disputes: a single file is enough for third parties to verify the entire action independently.

### Which format does an evidence pack use?

KYA describes the kya-pack/1 format in the open verification profile; a JSON schema is available for download.

### Can I create my own evidence pack?

Yes. The kya-pack/1 format is described in the open verification profile, and a JSON schema is available. The public test vectors show complete examples.

### What happens if a part of the pack is missing?

Then KYA verifies the parts that are present and states in the certificate which statement is not proven. If the timestamp is missing, for example, the pack can be valid but does not reach the highest level, KYA-A4.

## Sources

- [KYA verification profile](https://knowyouragent.ch/en/standard/verification-profile)
- [Schema kya-pack/1](https://knowyouragent.ch/schemas/kya-pack-1.schema.json)

## Related terms

- [Agent mandate](https://knowyouragent.ch/en/knowledge/glossary/agent-mandate)
- [Decision token](https://knowyouragent.ch/en/knowledge/glossary/decision-token)
- [Receipt chain](https://knowyouragent.ch/en/knowledge/glossary/receipt-chain)

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Quelle: https://knowyouragent.ch/en/knowledge/glossary/evidence-pack · KYA – Know Your Agent